Chapter 23:  

Why is the cardiovascular system a closed delivery system?

Blood Vessels:  

1. Why is the cardiovascular system is a closed delivery system? because doesn’t open to  anything and begins/ends at heart.  

2. What are the the blood vessels referred to as? vascular system.  

3. Why is the vasculature dynamic? They change to the changing needs of body by getting  larger or smaller (vasodilation/constriction), and proliferate (increase in numbers)  4. What are the functions of the cardiovascular system dependent on? Cardiovascular  system is dependent on what happens at capillary level because capillaries are site of  exchange- moves products in and out through diffusion.  

5. Why is diffusion so valuable? It’s a passive process that costs us NO energy 6. Why do arteries branch? Arteries branch because they are leaving heart in large arteries  and then delivering oxygen to tissues throughout the body.  

What are the functions of the cardiovascular system dependent on?

7. Why are veins are joining? because they are returning blood to the heart  8. What is a companion vessel? It’s both an artery and vein that travel together to supply  the same body region with blood supplies.  We also discuss several other topics like What are the bases for the legitimation of structure inequality?

9. What are capillaries designed for? Erythrocytes to move through them in single file  (rouleau formation)  

10. What does an anastomosis represent? Where two or more arteries/ veins converge and  provide blood to same region.  

11. Why is an end artery is detrimental? Why is is so bad to have it blocked? End artery  (small anastomoses) provides a limited alternate pathway, if any. So if the blood flow is  blocked, the tissue is left without oxygen. (ex. coronary artery)  

12. What is a “functional end artery”? An end artery that loses function because of lack of  alternative pathway  

What does an anastomosis represent?

13. Which vasculature forms more anastomoses? veins (remember that veins converge/join)  14. What are the three layers (tunics) of blood vessel walls? Tunica intima , Tunica media,  Tunica externa  

15. What is the functional importance of the structure of Tunica intima? It’s the innermost  layer- smooth layer/slick surface. This type of structural surface (slick) provides little  turbulence to allow blood to flow through easily and avoid forming plaques.  

16. What is the functional importance of the structure of Tunica media? It’s made of smooth  muscle that controls the blood vessels diameter: regulates the constriction and dilation of  vessel, thus controlling how much blood flows through at a time.  Don't forget about the age old question of What is hematopoiesis?

17. What is the functional importance of the structure of Tunica externa? It’s used to protect,  reinforce and stabilize the blood vessel by anchoring.  

18. No matter the size of an artery, what can you find? Vaso vasorum.  

19. What is the Vaso vasorum? A vaso network that assists with providing nourishment  (blood supply) to the blood vessel wall.  

20. Aside from the layers of tunica, what other layers are in blood vessels (in arteries)?  internal and external elastic lamina  

21. How do the two elastic lamina layers differ? thickness, diameter, and location.  22. What are located in veins only? Valves  

23. what is the function of valves? Vales help with blood flow of large veins

24. what makes up valves? folds of tunica intima  

25. Do capillaries have the tunicas? No, they are designed for exchange so they don’t have  all those layers and have thin walls.  

26. Why does an artery have much thicker layer of tunica media? To make sure blood gets  to where it needs to be.  We also discuss several other topics like What is used to test a theory?

27. Why system is more complex: veins or arteries? Arteries are more complex, with more  tunica media, to ensure that the organs are supplied with oxygen. Remember that for  veins, the blood is basically “drained” to heart so it’s an easier process/less work.  

Arteries:  

As diameter decreases, there is a decrease in elastic fibers and an increase of smooth muscle.  There are 3 types:  

● Elastic arteries-  

○ “conducting arteries”  

○ main job: take blood away from the heart  

○ example: aortic  

○ has low resistance pathways  

○ has elastin fibers that are found throughout tunicas (no internal/external lamina)  ○ they have a pressure smoothing effect -  

● Muscular arteries  

○ job: distribute blood to specific organs  

○ their tunica media is thick to have greater control over vasoconstriction and  vasodilation  

○ they deliver and control blood flow to specific organs  

○ less resilient (has elastic lamina)  Don't forget about the age old question of Cladogenesis (aka branching evolution)

● arterioles  

○ found in “two” sizes

○ adapted for control over vasoconstriction and vasodilation  

○ functions to regulate minute to minute changes of the environment  

Capillaries:  

1. what type of cells make up capillaries? endothelium (simple squamous)  2. what type of unique cells are found? pericytes  

3. what are pericytes? smooth muscle like cells used to stabilize cell wall  4. are pericytes continuous? not continuous  

5. how thick are capillary walls? very thin to allow for diffusion (quick exchange) 6. what is important about the branching of capillaries? The branching allows the blood to  slow down so that exchange can occur.  

7. Capillaries are functional units of cardiovascular system.  

8. Capillary beds function with capillaries to facilitate diffusion.  

9. You do not have enough blood in body to fill all the capillary beds in your body.

10. What controls if blood is in the capillary beds? We have precapillary sphincters that  contract and relax to allow blood in and out of beds. They go through cycles of  contraction and relaxation to fill beds or shunt blood through (from artery to vein side).  

11. What is Vasomotion? Vasomotion is the 5-10 cycles per minute of contraction and  relaxation. Rate/cycles depend on how heavily the tissue needs oxygenated blood.  12. What are the types of capillaries? continuous, fenestrated, sinusoids  13. What unites all capillary types? They are all designed for exchange but the difference is  that some are more continuous than others.  We also discuss several other topics like Race and the status attainment process.

Continuous capillaries are the most common type that are joined by tight junctions but with  some gaps between them.  If you want to learn more check out 4 steps to life on early earth

● What are these gaps called? intercellular cleft  

● What are the functions of intercellular cleft? limited exchange of fluids and solutes  ● pinocytotic vesicles- used to ferry fluids across capillary wall  

Fenestrated capillaries:  

● examples: GI tract  

● different from continuous because they contain pores or fenestrations  ● function: allows for exchange and usually found where active absorption or filtration  occurs  

● in kidneys  

Sinusoid capillaries:  

● VERY leaky!  

● designed for passage of large molecules  

● set up so that flow is very slow  

● huge intercellular clefts  

● huge lumens  

Veins:  

1. What is the pattern of diameter and thickness with veins? They increase in diameter and  wall thickness as they get closer to the heart.  

2. What are venules? When capillaries merge (small), very porous, allows fluid and white  blood cells to move from bloodstream to tissues  

3. What is unique about venules (how do they work with lymphatic system)? Venules are  the type of veins that are used to move lymphocytes to sites of infections  4. What makes up veins? Veins have the 3 tunics (thin tunica media & thick tunica  externa), large lumen, walls are thinner. Veins accommodate large blood volume by  serving as blood reservoir.  

5. How much of the blood supply to veins account for? Veins contains 65% of body’s blood  supply  

On the venous side of heart, is the pressure high or low? the pressure is low on venous side  (right side of heart)  

1. what are the adaptations of veins to help with blood movement? Larger diameters,  venous valves, skeletal muscle pumps, and a respiratory pump.

2. Why is a larger in diameter important? It creates lower resistance = blood flows easier  3. Why are venous valves important? Valves prevents backflow in low pressure system (no  mixing of blood)  

4. What are valves constructed of? folds of tunica interna  

1. where are valves located? placed strategically in veins of limbs  

2. what are the functions of valves? to compartmentalize blood between two valves. This  makes it easier to move blood- because blood is moved through one valve at a time. This is improves venous return.  

3. Can you describe the functions of the skeletal muscle pump? When the skeletal muscles  are stretched, it helps to move blood through venus portion of your skeletal circuit.  4. Can you describe how the respiratory pump works? When you inhale in, you increase  blood flow into thoracic cavity. When you exhale (out), you increase blood flow into  lungs.  

Summary:  

1. What is the flow of blood from heart to body to back to heart? Blood  is sent through arteries → arterioles → capillaries → venules →  veins → heart

2. What does T.I.M.E. represent in relation to the makeup of veins? Tunica intima Media  Externa (inside to out).  

Blood Pressure:  

1. What type of pressure represents contraction? systole = systolic pressure (highest  pressure)  

2. What type of pressure represents relaxation? diastole = diastolic pressure (lowest  pressure)  

3. Where does the biggest “smoothing” of pressure takes place? in aorta  4. What is Hydrostatic pressure (mmHg)? the amount of push/pressure that blood puts on  vessel walls  

5. Why are the adaptations in veins important to get blood back to heart? Important  adaptations that to move blood even though the pressure is so low in veins.  6. What is the pressure gradient? (between 100 and 0) it’s the difference of blood pressure  within that vasculature circuit. blood pressure is the driving force that keeps blood  moving.  

How to influence blood pressure: increase blood volume, increase cardiac output (amount of  blood pumped out of heart), vasoconstriction

Chapter 28

1. Why can you live without your reproductive system? You don’t need it to survive  as an individual, just as a species you need it so that you have continuation of  your species.  

2. Why is the reproductive system quiescent? It’s inactive/quiet until puberty.  Puberty is the time of reproductive maturity so that you can now successfully  reproduce.  

3. What organs does the reproductive system include? gonads, ducts, accessory  glands, and external genitalia  

4. Do you start out with a gender? No, for the first 7-8 weeks you are sexually  indifferent.  

5. What causes male? The activation of SRY gene initiates the sexually indifferent  gonad to become a testes (male) if activated. The SRY gene is the sex determining region of Y chromosome.  

6. What happens if the SRY gene is not activated? You’re female!  7. When you are sexually indifferent, what are the two duct systems? Mesonephric  duct (Wolffian duct) and Paramesonephric duct (Mullerian duct)  8. In males, what duct system is used? Wolffian duct (Mesonephric duct)- forms  duct for epididymal duct  

9. In females, what duct system is used? Paramesonephric duct (Mullerian duct)  forms the oviduct and uterus, and a small portion of vagina  

10. How long is the window for the SRY gene to become activated? 2 week window.  11. What happens if the androgen is blocked and you have male chromosomes  (XY)- and you have estrogens presence? Then you have a genotypic male( XY)  but a female phenotype (XX)  

12. Why is the male reproductive system a continuous system? Because it deals with  anatomical construction of the perms journey: start in testes move to epididymis  to ductus deferens then to ampulla to ejaculatory duct and then it joins the  urinary system and use the urethra. Anatomically speaking there is no breaks, it  goes from one anatomical region to another.

13. What is the process of testicular development? At the 7th month of  development, the gubernaculum contracts to pull testis through inguinal canal to  form scrotum. Thus, the testes comes down but part of the parietal peritoneum  comes down also to form the tunica vaginalis. This parietal layer that is also  pulled down is a serous membrane that allows testicular movement within the  scrotum sac.  

14. What is the spermatic cord made from? The ductus deferens, testicular blood  vessels, nerves and lymphatic vessels  

15. What is the one structure not present in spermatic cord? lymphatics  16. What is the gubernaculum? This is a bundle of CT fibers that extend from testis  to floor of scrotal swelt (scrotum). As this structure grows, it does not actually  change length, it only changes position.  

17. What structures make up the testes? The testes has a parietal and visceral  layer, which are serous membranes to allow movement. The testes are wrapped  in tunica albuginea - this CT invaginates into vastus proper to form septa, which  then finds globulus to form seminiferous tubulus.  

18.What is spermatogenesis? It’s the structurally maturation of sperm cells that  occurs in the lumen of seminiferous tubules  

19. What is the mediastinum testis? It forms the network called rete testis and is a  site of entry into testes proper for vasculature.  

20. What are the two compartments of the seminiferous tubule? The seminiferous  tubule is made up of sertoli cells (sustentacular cells) that forms tight junctions  that form: Basal and adluminal compartment.  

21. What is significant about the basal compartment?It’s the site where  spermatogonia occurs- and it’s located close to the basal lamina 22. What is significant about the adluminal compartment? adluminal compartment  needs to be separated from immune system to form blood-testis barrier.  23. What is significant about the blood-testis barrier- formed by these two  compartments? This barrier does not allow large molecules pass through. This is  important to keep spermatogonia, spermatocytes, spermatids, and mature  spermatozoa from blood so that the immune system does not become introduced  and try to kill the sperm bodies. This is what causes many men to become  infertile.  

24. Where are the testis located? outside of body  

25. What is the cremaster muscle?it’s skeletal muscle that is derived from internal  oblique muscle and it covers the spermatic cord and testis.  

26. What is the function of the cremaster muscle? Functions to retract testis (brings  testes closer to body to keep it warm or relax to allow more circulation testes)  27. What is the dartos muscle? smooth muscle within scrotal wall

28.what is the function of the dartos muscle? temperature  regulation of testis by causing wrinkling of the scrotum → more  SA to retain more heat when it’s cold. when it relaxes, the  surface area decreases so heat radiates

29. What two muscles are important in spermatogenesis? cremaster and dartos  muscle - because spermatogenesis depends on temperature  

30.What is the structure referred to as raphe? It’s the line that results from the union  between two contiguous, bilaterally symmetrical structures. But it has nothing to  do with reproduction.  

31. What is a plexus? interweaving network of something  

32.What’s the significance of pampiniform plexus? It provides a countercurrent  mechanism as a heat exchange. As warm arterial blood flows into the testes it is  wrapped by a section of the testicular vein- where it becomes the pampiniform  plexus within the spermatic cord. So blood is cooled as it enters testis, but  warmed as it leaves the testis. This mechanism is a way to make sure the testis  remains correct temperature so that spermatogenesis can be successful.  

33. What is spermatogenesis? A progress of forming a structurally mature sperm  cell through meiosis. It continues constantly from time of puberty. It starts with a  spermatogonia and ends with a sperm.  

34. Are spermatogenesis ells seen as self? Yes- but cells modified after this process  are seen as non-self.  

35.What is spermiogenesis? IT’s a part within spermatogenesis that focuses on the  reconstruction of the round spermatocyte into a structurally mature sperm with an  acrosome cap (head), nucleus, mitochondria, and a tail (flagellum).  

36. What is spermiation? Another process that sperm undergoes when sperm loses  attachment to sustentacular cells.  

37. What are the 3 regions of the epididymis? caput (head) - where sperm comes in,  corpus (body), and the cauda (tail/end)  

38. What is the function of epididymis? It monitors/adjusts fluid composition to  support developing cells, is a recycling center for damaged sperm (anything  “bad” is reabsorbed and taken away), stores, protects, and facilitates functional  maturation of sperm. And most importantly, sperm earns “diploma” saying they  have learned how to swim in epididymis and now have capacity to fertilize  

39. Where does sperm go from testes? sperm moves along epididymis via peristaltic  contractions of wall smooth muscle. so sperm is constantly move to caput/head,  corpus and cauda of epididymis.But it’s stored in tail/cauda region until  ejaculation.  

40. After the sperm leaves the cauda region of the epididymis, where is it sent to?  Through ductus deferens, and ampulla (storage cavity within body cavity) of

ductus deferens, then to ejaculatory duct the seminal vesicles then it’s joined with  the urethra to exit the penis.  

41. What tissues make up the ductus deferens? thick layer of smooth muscle and  lined with pseudostratified ciliated columnar epithelium.  

42. So all together, what is the Sperm’s journey? testes →  epididymis (caput to corpus to caudal)→ ductus deferens →  ampulla → seminal vesicle → ejaculatory duct → prostatic urethra  → urethra

43. what are the accessory glands? seminal vesicles, prostate gland, and  bulbourethral gland  

44. What is the function of the accessory glands? provides fluid medium that is part  of the semen that sperm is suspended it. The fluid provide nutrients and  functional maturation  

45. What is the function of the seminal vesicles? It makes 60% of the fluid  composition of the semen. The secretions high in fructose - sperm’s favorite  energy source.The fluid is slightly alkaline - because female reproductive tract  which is slightly acidic so having buffers is important. it helps to keep gametes in  the female reproductive tract. causes contraction of vagina muscles to keep  sperm in there. the human semen actually gels to help it stay and protect it from  environment - helps it into cervix.  

46. What is the function of the prostate gland? It’s slightly acidic and contains  seminalplasmin to help get rid of bacteria. The prostate gland is wrapped in  smooth muscle, encircles the urethra, and produces prostatic fluid.  

47.What is the function of the bulbourethral gland? (Cowper’s gland). This is a  tubuloalveolar mucous gland that primarily secretes thick mucus that is alkaline.  48.What is semen? in human it’s milky white, someway sticky (because presence of  fructose). mixture of sperm and accessory gland secretions.  

49. What is the function of semen? provides a transport medium, nutrients,  chemicals to protect and activate sperm. It also facilitates sperm’s movement 50. What are the two functions of the penis? conduct urine to exterior and also used to deposit male gamete in female Reproductive tract  

51. What is the erectile tissue of the penis made of? it’s a dense network of elastic  fibers. largest erectile tissue in body, not the only location of erectile tissue.  There are vascular channels moving through it. it’s a spongy network of  connective tissue and smooth muscle riddles with vascular spaces. so vascular  channels that are separated by networks of connective tissue and smooth  muscular fibers  

52. What are the 3 cylinders/columns of erectile tissue? There are 2 corpus  cavernosum columns and one corpus spongiosum. The corpus cavernosum  contain a central artery, and the corpus spongiosum has the spongy urethra.

53. What allows the movement of erectile tissue with skin? deep fascia that allows  tissue to become flaccid and erect  

54. why is it better to use this type of erectile tissue- why have cylinders of erectile  tissue-why erectile tissue instead of just a hollow tube? it offers structural  support! erectile tissue gives better rigidity and more structural strength with this  anatomical design  

55. What are the two blood supplies of the penis? one is blood supply that provides  regular nutrients and one is helicine arteries (these are actually involved with the  functionality of the erectile tissue).  

56. How does erectile tissue function? vasodilator impulses from parasympathetic  NS

This causes relaxation of penile vessels → allows the blood flow  into erectile tissue. As the tissue fills with blood, this  creates a high pressure system that traps the blood within penis  to sustain erection. The drainage elements are found more  peripherally (on the sides), so as the erectile tissue flows in,  it blocks the drainage vessels flow. so by trapping the blood  flow, erection is sustained. At the same time are are going to  suppress sympathetic NS

57. How is ejaculation completed? It’s coordinated by sympathetic nervous system.  The contractions of vas deferens and have “sweeping” peristaltic contractions in  penile urethra (also in urethra as well) to move sperm through series of ducts  

58. What action is completed by the parasympathetic system? Erection (point)  59. What action is completed by the sympathetic system? ejaculation (shoot)  60. What stimulates the anterior pituitary to send LH and FSH to gonads?  hypothalamus produces GnRH  

61. What does LH do? stimulates the leydig (interstitial) cells release testosterone  62.  

63. What hormones does spermatogenesis require? both FSH and testosterone  64. What does prolactin do for a male? This increases sensitivity of interstitial cells to  LH. prolactin is supportive of LH influencing interstitial cells and making sure they  are producing testosterone.  

65.What is the importance of Inhibin? It serves as a “sperm barometer” because  when sperm numbers increase, then the testes releases more inhibins  66. What is the function of inhibin? shuts down the release of the gonadotropins  (shuts down GrnH) because it tries to help regulate the number of sperm being  made and keep it within a normal range. Thus, when sperm numbers decreased,  inhibin secretion declines so the release of gonadotropins increases to lead to  sperm production.

67. Why is the female reproductive system discontinuous? there is a break in the  system at the ovaries. the ovaries expel oocytes (side note: this is how you get  ectopic pregnancies). the ovaries are where oogenesis occurs and expelled- to  be picked up from oviduct - which is picked up by the fimbriae (finger like  structures of oviduct) then it goes into the uterus and then goes into the vagina.  oocytes don’t have to go into the oviduct- they can go away into the nearby  tissues. same thing for sperm that enters female tract- can go away. doesn’t  have to go into oviduct. can be found in fluid/tissue surrounding.  

68. What are the structures that anchor the ovaries and uterus? fimbriae/oviducts,  broad ligaments, suspensory ligament, ovarian ligament.  

69. What is the structure fimbria? hangs over uteries (fimbriae holds ovaries)  70.What is the broad ligament? It’s the “cape”, which is made of peritoneum that  folds over the structures of the female reproductive system  

71. What are the two ligaments that keep ovaries stationary? Suspensory and  ovarian ligaments.  

72. What is the structure of suspensory ligaments? They attach ovary to the body  wall. This is where vasculature comes into this suspensory ligament  73. What is the structure of ovarian ligaments? They are posteriorly located, attaches  to uterus to ovary to keep ovary in place . important to keep it in reach of fimbriae  74. What is anteverted? where uterus is inclined forward. Note: most young women  our age should have this  

75. What is retroverted? uterus is turned backwards toward rectum (as you age it tilts  this way)  

76. What are the two domains of an ovary? medulla and cortex  

77. What is the structural characteristics of the medulla? It's the inner layer that  vasculature and lymphatics comes in through the suspensory ligament  78.What’s the structural characteristics of the cortex? It’s the outer layer where  follicles develop.  

79. What are primordial follicles? these are recruited oocytes during each cycle  (usually 10-15). they then flow through grow to be a mature follicle.  80. What are mature follicles? (vesicular follicles)- They are a fluid filled antrum with  oocytes with zona pellucida and corona radiata  

81. After the follicle is mature, what happens? the follicle is ovulated and then the  follicle then converted into corpus luteum  

82. What are oogonia? These are diploid cells that divided by mitosis. (equivalency  in males is spermatogonia)  

83. What is the difference between male and female reproductive cells? in adult  male, you have presence of spermatogonia. stem cell is retained.in females, right  before birth- the oogonium starts in meiosis and becomes arrested. this means  that women are born with their full compliment of oogonium. Women are born

with all the oocytes they will ever have. This is different from male that continually  produce spermatogonia  

84. Why is radiation bad for both males and females? bad for males because  spermatogonia are ready to divide. bad for females because they have their  whole set that they are born with.  

85. What is the process of the reproductive cycle of females? each month, up to 20  primordial follicles mature into primary follicles. from there, only one of the  primordial follicles develop into secondary follicles. the primary follicles that do  not mature into secondary follicles undergo atresia. the one primary follicle that  matures into secondary follicle completes the first meiotic division. This creates a  polar body and a secondary oocyte. This secondary oocyte is a haploid cell (23  chromosomes) and pauses in the second meiotic metaphase. Only if it is  fertilizes does this secondary oocyte complete the second meiotic division to  become an ovum. if not fertilized, it is degraded.  

86. once primordial follicles are recruited and undergo development, what happens  next? they undergo mitosis and stop right before meiosis 2.  

87. What is menarche? first reproductive cycle  

88. what is menopause? one full year without reproductive cycle (and not pregnant)  then you are officially in menopause  

89. How many sex cells are created for each reproductive system? For males,  spermatogenesis ends up with 4 structurally mature sperm cells (4 gametes) and  for females we end up with 1 ovum. the extra genetic material is released as first  and second polar bodies.  

90. why one ovum and 4 sperm? This difference is because the uterus is set up for  one, maybe 2 young. all the elements are in place for the first cell division. ovum  has all the nutrients are there. until the nucleus for the first zygote can take over  and use it’s own genetic material -which takes time. so that’s why the ovum is  such a large cell - it houses and provides energy for the first division for the  zygote.  

91. How many oocytes are ovulated each cycle of female reproductive 1-2 oocytes  per cycle  

92.What does meiosis result in? diploid cell → haploid cell  93.What does mitosis result in? diploid cell → diploid cell  94. What are the two phases of the ovarian cycle? follicular and luteal phases  95. What is the follicular phase? represented by recruiting one of these primordial  

follicles and progress under series of events to turn into mature (or graafian)  follicle which is a cell that’s ready to ovulate. during these time,this mature  follicle produces estrogen. then we have ovulation  

96. What is ovulation? ovulation is like an eruption because the walls of follicle thin  and the pressure inside builds. so the oocyte “pops out”

97. What causes ovulation? rise in gonadotropins (FSH and LH, LH is larger force).  important because it’s then going to affects the cells left over in the follicle. this  represents luteal phase. these cells go through luteinization. under impression of  LH. take the follicle that was making estrogen, now undergo morphological  changes to become the corpus luteum and make progesterone. this change in  hormone product being produced = steroidogenesis to produce progesterone.  luteal cells produces the progesterone. remains active and has a timer: has a  signal for pregnancy - to maintain corpus luteum is maintained if pregnant. if the signal is not maintained, the cycle restarts again. follicle cells produces estrogen  98. What is the luteal phase? remains fairly constant  

99. What are the oviducts? hollow muscular tubes that are held up by broad  ligaments and open into the peritoneal cavity.  

100. What are the segments of the oviducts? Infundibulum, ampulla, isthmus  101. What is unique about the infundibulum of the oviduct? The ends have  fimbriae that are close to the ovary (but not attached to) to pick up the egg.  102. What occurs in the ampulla region of the oviduct? fertilization occurs here.  103. What occurs in the isthmus of the oviduct? This structure connects to the  uterus and is the site of fertilization. This region serves as “sperm reservoir” . 104. What happens to the sperm as it enters the vagina? As sperm comes into  vagina, sperm “takes a break”/comes immobile on isthmus of oviduct so that they  reach the infundibulum at different times. This method decreases risks of missing  ovulated egg because the egg is continually met by sperm.  

105. What is the functionality of the oviduct? It’s designed to receive the  oocyte, be the site of fertilization, and preimplantation of development (until the  zygote heads to uterus).  

106. What is an ectopic pregnancy? It’s when the fertilized egg doesn’t go into  the uterus, so it’s growing in the fallopian tube.  

107. What’s significant about the uterus? It’s the hollow, muscular muscular  organ that houses the embryo.  

108. What helps the uterus have limited movement? muscles and ligaments  109. What are the 3 anatomical subdivisions? Fundus, corpus, cervix  110. What is the fundus? dome shaped superior portion  

111. what is the corpus? the body (middle region)  

112. What is the certix? the bottom basement of uterus- inferior narrow portion opens into vagina  

113. What shape does the human female uterus resemble? a triangle because  it has a simplex, inverted design where the larger portion is superior with a  narrow base.  

114. What is the function of the uterus? serves as a site of implantation and  embryonic/fetal development, and also parturition

115. What are the 3 layers of the uterine wall? endometrial, myometrium, and  perimetrium  

116. What is the endometrial layer made of? It’s a mucosal lining made of  simple columnar epithelium on top of a thick, robust basal lamina. it’s made up of  two elements: stratum functionalis and stratum basalis.  

117. Where is the stratum functionalis located? Next to the lumen  118. What is the functionality of the stratum functionalis? It responds to the  hormonal environment- so it undergoes the cyclic changes in response to the  hormonal changes from estrogen to progesterone. this layer is fed by a spiral  artery( coiled arteries). This layer is lost during menses.contains most of uterine  glands. This is a thick layer.  

119. Where is the stratum basalis located? It sits next to myometrium.  120. What is the stratum basalis? It’s a thin layer fed by straight artery. also has  uterine glands. This is the foundation for new functional layer after menses.  121. What is the structure of the myometrium? It has no distinct layers. It’s  made of interwoven smooth muscle bounded together.  

122. What is the structure of the perimetrium? It contains a serosa layer  (visceral peritoneum)  

123. What are the 3 phases of the uterine cycle? Menses, proliferation, and  secretory.  

124. What happens in menses? It’s the degeneration of  endometrial functional zone. The endometrial layer breaks down  in patches because of the constriction of spiral arteries.  However, the entire endometrial functional zone is lost →  menstruation. (menses is actually a lack of hormones).  

125. What happens in the proliferative phase? The endometrial basilar zone  grows to restores integrity of endometrium by forming the functional layer. growth  and vascularization is restored in functional layer. supported by estrogen.  

126. What does estrogen and progesterone do? estrogen builds. progesterone  maintains.  

127. What happens in the secretory phase? There is an enlargement of uterine  glands along with increased secretory rate and elongation of coiled arteries.  tissues maintained by progestins.  

128. What happens when hormones releases decline? The spiral arteries  respond by constriction - which leads to menses and so the whole uterine cycle  begins again.  

129. Do the straight arteries respond to hormone levels? No, the straight  arteries are insensitive to hormone levels. so the stratum basalis is never really  affected by hormonal changes because it consists of straight arteries.

130. What is amenorrhea? It’s the loss of reproductive cycle. There is a  correlation between amount of body fat and reproductive cycle. Because the  female reproductive cycle is very costly- it requires a certain amount of body fat  to have a cycle. So without meeting the fat requirement, there is no cycle.  131. What is dysmenorrhea? It’s painful menstruation

132. What is the vagina? It’s a thin-walled elastic  fibromuscular tube that extends from certix → vestibule  133. What’s the functionality of the vagina? It serves as birth canal, serves as  passage for elimination of menstrual fluids, and a site of semen deposition. So  basically a conduit or deposition place  

134. What’s the structurality of the vagina? It has vaginal rugae. This is  important because the folds in the inner layer provides flexibility to stretch. the  primary tissue type of this mucosal membrane is connective tissue and  epithelium. (remember epithelium doesn’t allow stretching. and connective tissue  is somewhat stretchy. So rugae of mucosal folds allows structure to stretch  without tearing.  

135. Who has mammary glands? Both men and woman.  

136. What are mammary glands? a specialized organ of integument - modified sweat gland.  

137. What do mammary glands do in women? produce milk (lactation for  newborn offspring)  

138. What hormones regulate lactation? prolactin stimulates milk production  and oxytocin activates smooth muscles that helps with milk injection/”milk let  down”.  

139. Do guys produce prolactin? Yes, prolactin is supportive of gonadal activity.  Males also produce oxytocin  

140. What does oxytocin do? oxytocin stimulates smooth muscle  contraction in male reproductive system. oxytocin also referred  to as ȩcuddleȪ hormone because it does enhance pair bonding and  maternal behaviors. elevated levels of oxytocin found in mated  pairs. also may be connected to limbic system. evidence: when  couples cuddle their oxytocin levels rise → brings down cardiac  output and heart beat, which brings down blood pressure. makes  you more relaxed, lessens stress and anxiety.  

141. What are accessory parts to mammary glands? ductal system and milk  producing alveoli. Females have both but males only have ductal system.  142. What is gynecomastia? “man boobs” - excessive development of male  mammary glands due to ductal proliferation due to increased estrogen levels.

Seen mostly at time of puberty in males because sex hormones are being  produced.. But over time the tissue is reabsorbed and the mammary structures  will not longer exist.  

143. How do males males produce estrogen just like they produce  testosterone? because the zona reticularis produces gonadocorticoids  (estrogens and androgens)  

Chapter 22- Heart

1. How does blood help to maintain homeostasis? It circulates continuously  throughout the body.  

2. How is blood able to circulate continuously? via the pumping action of the heart  and adjustment of pressures because circulation is a closed system.  3. What is the flow of blood? body to inferior vena cava to RA to RV to pulmonary  trunk to lungs to pulmonary veins to LA to LV to aortic to body  

4. What are the functions of the heart? Serving as a pump to propel blood through  vessels.  

5. What are the main vessels of the heart called? Great Vessels  6. Why is the heart the “Center” of cardiovascular system? because blood is  brought to the heart and sent away from the heart  

7. What are the conduit systems of blood vessels? Arteries, veins, capillaries  8. What is the function of arteries? always carry blood AWAY from heart  9. Do arteries always carry oxygenated blood since they carry blood away from the  

heart? No, it’s not always oxygenated. The exception is pulmonary artery  10. What is the function of veins? always carry blood TO the heart (not always  deoxygenated; exception is pulmonary vein).  

11. What is the function of capillaries? Capillaries are the functional unit that is the  site of exchange  

12. What are the anatomical characteristics that assist with function? Unidirectional  flow, side-by-side pump, and blood pressure  

13. What is the mechanism for blood flow through vessels? A pressure gradient is

used to move blood through blood vessels  

14. Why is the heart a “side-by-side” pump? It serves 2 separate blood circuits  (pulmonary and systemic circuit?

15. Because the circuits of the heart have equal volumes of blood, do they also have  the same amount of work? No, the right side requires less work because  pulmonary circuit is short, and low pressure system.  

16. Why does the systemic Circuit (left side) require more work? It is longer (sends  blood to limbs) and is more resistant to blood flow  

17. What is the weight of the heart? modest weight (~300 grams or 1 pound)  18. What is the size of the heart? about the size of your fist  

19. What is unique about the weight and size of heart? masks incredible strength  and endurance to pump all blood needed each day  

20. Where is heart located? located in thoracic cavity between lungs within  mediastinum between 2 and 5th rib. superior to diaphragm. extends obliquely to  mediastinum. posterior to sternum. anterior to vertebral column. obliquely placed  21. Where is the apex of the heart? tip of heart at bottom  

22. Where is the base of the heart? the top region  

23. Is the heart completely vertical or tripped? tipped:apex is tipped anteriorly  (forward), base is tipped posteriorly (backward). thus, obliquely oriented.  24. On which side of the body is the heart located? and heart is more to the left of  body

25. What is the double-walled sac that the heart is enclosed by called? pericardium 26. What is the pericardium constructed of? fibrous pericardium, serous pericardium  27. What is the fibrous pericardium made from? loose fitting, tough dense  connective tissue layer  

28. How does the fibrous pericardium protect your heart? The fibrous pericardium  wraps around heart, anchors heart to surrounding structures to prevent it from  overfilling so you don’t “blow out” the wall of your heart.  

29. What two layers does the serous pericardium have? parietal and visceral layer  30. Where is the parietal layer? It lies next to the fibrous pericardium- it’s the outer  layer that lies next to the fibrous pericardium.

31.Where is the visceral layer located? It’s the innermost layer of serous  pericardium. The visceral layer consists of the epicardium, myocardium and  endocardium .  

32.What is the “epicardium”? The outermost part of the visceral layer that is an  integral part of heart wall.  

33.What is the myocardium? It’s packaged in spiral/circular bundles- uses  connective tissue to crisscross fibers to link areas of heart together. The  crisscrossing is important because it allows the heart to twist as it contracts to  squeeze the blood out of the ventricles. It compresses the heart to pump large  amounts of blood out of ventricles.  

34. What is the endocardium? The innermost layer, deepest layer of the visceral  layer. It’s made up of layers of endothelium supported by connective tissue.  Remember that endothelium is simple squamous epithelium.  

35. What is special about the endocardium regarding valves and vessels?  Endocardium endothelium is continuous with the endothelium of the vessels that  are leaving the heart and also covers the valves of the veins.  

36. What is the pericardial cavity? A slit like structure between layers of serous  pericardium containing film of serous fluid. This is important because it permits  free movement within sac. Every time the heart contracts and beats- it moves. so the serous fluid is important to provide friction free environment.  

37. What structure does Cardiac muscle tissue have? Cardiac has intercalated disks  provide “interlocking” of the cardiac muscles together.  

38. What two elements make up intercalated discs? desmosomes & gap junctions  39. What do desmosomes do? keep the cells attached to keep them from pulling  apart during contraction with all the pressure  

40. What do gap junctions do? set up a situation where they are electrically coupled.  so once we have a depolarizing wave on one cell, it spread to all cells.  

41. What forms a functional syncytium? Intercalated discs form syncytium because  these discs allows a bunch of individual cells to work as a single unit. result in  highly coordinated contractions.

42.Where is the nuclei found in intercalated discs? in center. (in skeletal muscle it’s  peripherally located)  

43. What type of tissue is located between the intercalated discs? loose connective  tissue - the matrix fills intercellular spaces along vasculature to connect to fibrous  skeleton of heart. It acts as a tendon to provide an insertion for cardiac muscle  tissue. Know that microscopically: cardiac muscle cells have sarcomeres, z lines,  A bands, I bands, etc. but has numerous mitochondria to give cardiac muscles  high resistance to fatigue, which is important because we don’t want heart to stop  beating.  

44. Compared to the skeletal system, is the calcium delivery system more or less  developed? It’s less developed (less robust than skeletal muscle) and the T  tubules are wider and fewer. enter once per sarcomeres. no triads.  

45. At physiological level, is skeletal and cardiac muscle the same? They are similar,  but if you look at cellular level, it’s designed is slightly different.  

46. What is located in the fibrous skeleton between the heart valves (in a cross section)? A dense connective tissue network is found between atria and  ventricles. The functions of this dense CT is that it physically and electrically  separate atria and ventricles, anchor heart valves with supportive rings  (important because valves are just flaps of connective tissues), and provides a  rigid framework for attachment of cardiac muscles - reinforces myocardium  internally and anchors cardiac muscles.  

47. Where are the atria located? superior located. Also know they are smaller, and  thin-walled.  

48. Where are the ventricles located? inferior located. Also know they are larger,  thick-walled.  

49. Where do all of the vessels from the ventricles exit from? The base (basal  surface)  

50. What structures are on the anterior side? trunk or aora. or interventricular  sulcus.  

51. What structures are on the posterior side? inferior or superior vena cava &  coronary sulcus (coronary sinus sits on coronary sulcus)

52. What are the suli of heart? anterior and posterior ventricular sulcus, and  coronary sulcus  

53. What is the function of coronary sulcus? This specific sulcus holds coronary  circulation that provides heart with private circulation  

54.What’s significant concerning the opening of coronary sinus? It’s where blood  returns to heart in right atria  

55. What can all valves be called? all valves are atrioventricular valves  56. What is hooked to papillary muscles? tendinae  

57. Do the papillary muscles contract? No- the heart wall contracts and creates  tension on the papillary tendinae to cause movement.  

58.What makes sure the right ventricle doesn’t blow out in right ventricle?  septomarginal trabecular  

59.What is the significance/function of the trabeculae carnae? It’s the ridges and  valleys (remnant left over from when we had 2 chambers) that makes sure blood  doesn’t stay sedentary in the heart to prevent a clot - keeps blood flowing. heart  doesn’t eject ALL blood, some are residual.

60. What is function of semilunar valves? These valves are folds of connective tissue  on the wall that open and close depending on blood flow  

61. What is function of ligamentum arteriosum? This structure arises after birth -  remnant of ductus arteriosus (fetal structure that shunts blood) so this detours  from pulmonary trunk to the atria. this is bypassing pulmonary circuit- important  because fetus isn’t breathing. but once you are born, you can breathe so this is  closed off and becomes a fibrous structure.  

62. What is function of crista terminalis? The crista terminalis separates the pectinate  muscle from heart  

63. What is the function of the fossa ovalis? The fossa ovalis shunts between left and  right because we don’t always use full circuit. it’s a hollow depression where  foramen ovale existed in fetal heart.  

64.What’s the difference between left vs right ventricle? In left, the heart wall is  thicker because it pumps to the entire body. Whereas the right ventricle sends

blood to pulmonary circuit so it’s weaker because it’s a shorter distance with less  pressure and less resistance.  

65. What's the difference between atria vs ventricles? ventricles are larger. the  difference in function between atria and ventricles is reflected in size. atria  contract enough to fill up. atria are primer pumps. ventricles are power pumps  that generate pressure to move blood  

66. why is the heart constructed how it is- why is left larger than right ventricle- why  atria and ventricle size difference? because of the functional demands placed on  it. The left side= systemic. The right side- pulmonary circulatory.  67. How is a one-way flow accomplished? heart valves  

68. What makes valves open and close? They open/close in response to different in  blood pressure  

69. What is systole? ventricles contracting  

70. What is diastole? ventricles relaxing  

71. What happens when ventricles contract? The semilunar are open because  Ventricular pressure is greater than the systemic circuit. This is because heart  can only pump blood out when pressure inside ventricle is greater than pressure  in circuit.  

72. What happens as pressure falls in ventricles (relaxing)? This would make the  atria pressure greater so the atrioventricular valves open and fill ventricles.  73. What happens when systemic circuit pressure is greater than ventricular  pressure? blood flows back in through the atria and fills ventricles.  74. so why no valves on vena cavas or pulmonary veins- couldn’t blood backflow into  those? pressure is really low, the walls are thin, so when the heart contracts - the  heart compresses them shut so there is no backflow  

75. What happens to the atrioventricular valves when ventricles contract? Because  of the little blood in atria, there is no pressure so it creates compression to  prevent no backflow  

76. What is a cardiac cycle? it represents the period from the time of one contraction  (one heartbeat) to the next contraction/heartbeat  

77. class video: http://www.youtube.com/watch?v=rguztY8aqpk&feature=related

78.How is the heart coordinated to be an efficient pump? it’s coordinated by  conduction system - which is made up of specialized cardiac (myocardial) cells  that are noncontractile. They serve as a mechanism to distribute impulses that  are generated at sinoatrial node. so the heart contracts in orderly, sequential  manner.  

79. Why is the conduction system so important? conduction system ensures signal  moves fast enough through heart  

80. What does it mean that the heart has autorhythmicity? heart initiates its own  contraction through self depolarization. Thus, the heart does not need NS.  81. Where does a contraction originate? from the SA node -- internodal pathway  brings the signal to the right side and the atria contracts.  

82. What keeps order in the contractions of the heart? atrioventricular node - causes  a delay so the atria contracts and then ventricular contraction.  

83. What is the function of the AV bundle (bundle of His)? The AV bundle conducts  the muscle impulse into the interventricular septum  

84. What happens to the AV bundles once inside the the interventricular septum? the L and R bundles split from the AV bundle  

85. What type of fibers receive and distribute the muscle impulse in each ventricle  myocardium? purkinje fibers  

86. How is the heart innervated? By the autonomic nervous system via the coronary  plexus.  

87. What are the main layers of coronary plexus? sympathetic through cardiac nerve  and parasympathetic through the vagus nerve.  

88. What structure is used to set the pace of the conduction system of the cardiac  muscle’s contractions? pacemaker!  

89. so why need innervation of the heart? the brain stem can modify heart rate and  force of contraction. BUT they do NOT initiate contraction- that is by the  pacemaker (sinoatrial node)  

90. What is the function of the parasympathetic innervation of the heart? It decreases  heart rate

91. what is the function of the sympathetic innervation? increases heart rate and can  increase force of contraction  

92.What is the “3rd circuit”? coronary circuit - the coronary arteries arise at the base  itself and goes out to supply oxygenated blood to the heart  

93. What specific type of arteries are the coronary arteries referred to? functional  end arteries.  

94. What is the function of the functional end arteries? They have anastomoses - which allows us to have alternative blood vessels to have alternative pathways of  blood supply.  

95. What is the coronary sinus? coronary sinus is a large vessel that enters to the  right atrium  

96. What is an interesting fact on the heart? heart represents 1/200th of the body  weight but it requires of 1/20th of the body’s blood supply  

Chapter 21

Cardiovascular system= blood (transport medium), heart (pump) + blood vessels  1. blood is unique because it’s the only fluid tissue found in body.  

2. What tissue system does blood belong to? Blood belongs to connective  tissue  

3. What are the components of whole blood? plasma (nonliving fluid matrix) +  cellular components (formed elements)  

4. What are some physical characteristics of blood?  

a. sticky because of glucose components  

b. metallic odor  

c. denser/more viscous than water  

d. slightly alkaline (pH 7.35 - 7.45)

e. temperature slightly higher than body temperature (38 degrees C)  because blood is used to move heat within system.  

5. if you centrifuge blood, how will divide out into different layers of components?  a. plasma: 55%  

b. erythrocyte: 44%  

c. butty coat: <1%  

6. When you centrifuge blood, what are the colored layers? white, yellow, red  7. What does the white layer consist of? puffy coat  

8. what does the red layer consist of? erythrocytes  

9. what does the yellow layer consist of? plasma  

10. What is plasma? water + proteins + solutes (electrolytes, nutrients)  11. What are erythrocytes? red blood cells  

12. what is a buffy coat? white layer & platelets and white blood cells  13.hematocrit looks at percentage of erythrocytes (number of RBC)  a. males usually 45%, females around 40% mainly because menstruation. so  during menstruation years women tend to be anemic. during the years  younger than 35.  

Functions of blood:

1. Performs numerous functions that are important in the maintenance of  homeostasis  

2. Involved in substance distribution & regulation of blood levels of particular  substances as well as protection  

3. How are these functions accomplished?  

a. distribution: transportation to and from tissues.  

i. transporting oxygen, nutrients, enzymes & hormones to tissues  ii. transporting carbon dioxide & waste products away from tissues (to  kidneys/liver)  

b. maintaining body temperature

i. “moves” heat from deep tissues to body’s surface as you generate  heat. this helps to eliminate excess heat.  

ii. the surface of skin can come to outside temperature, like if it’s cold  outside, while maintaining a warm body core temperature  

c. maintaining levels of cellular components: fluid, electrolyte & pH balance  d. protecting body from disease-carrying microorganisms, foreign substances &  tumors  

i. cellular component of blood, antibodies  

e. preventing blood loss  

i. platelets & clotting factors  

Plasma:

1. fluid component that suspends elements of blood  

2. plasma = serum + proteins + chemical substances  

3. straw-colored, yellow color.  

4. sticky fluid  

5. composed of mostly water  

6. Comparing serum vs plasma:  

a. to get serum- you let old blood clot and then spin it now and take the  supernate off. so serum is plasma without the clotting factors.  

b. plasma- it’s serum (water portion) + array of proteins  

i. what do you find in plasma?  

1. water + proteins + electrolytes  

2. the most abundant plasma solute = plasma proteins  

7. plasma is not just a fluid, it’s a complex mixture that contains many different  solutes.  

8. homeostatic mechanisms serve to keep the composition of plasma relatively  constant, even though there are over 100 different dissolve solutes that can be  found in plasma

9. however if you look at blood in lungs or liver, the makeup of plasma is different  because the blood is constantly being added to as the body filters blood.  10. overall plasma is constant, but at tissue level there are changes of solutes  leaving/entering, new/old substances  

Formed elements are the cellular components of blood

● 3 players: erythrocytes, leukocytes and platelets  

○ erythrocytes - anucleated  

■ go for about 20 days  

○ leukocytes- complete cell  

■ may last 6 hours  

○ platelets- cellular fragments  

● in general, formed elements are short lived and amitotic so they must be  continually renewed. they are formed in red bone marrow.  

Erythrocytes:

● used for internal micrometers because they are always 7.5 micrometers in  diameter  

● look like biconcave discs: similar shaped to dumbbells  

● why a concave disc shape of erythrocyte?  

○ it allows us to have a large SA , which allows the movement of molecules  like gases by utilizes diffusion, which does not cost anything.  

○ also permit the stacking of erythrocytes next to each other = rouleau  formation is when they are stacked so that they can move through a small  vessels (capillary)  

● during development and as they go through erythropoiesis, they lose nuclei and  most organelles and just retains cytoskeletal elements with an interesting shape  ● plasma membrane sac with hemoglobin (a protein)  

○ other elements:

■ antioxidant enzymes (functional protein)  

■ spectrin (structurally important enzyme) - attaches to plasma  

membrane and allows them to twist/change shape and allow them  to spring back to original shape - allows them to fit through blood  

vessels. helps them flow through capillaries. provides RBC  

flexibility  

● erythrocytes contributes to viscosity/fluidity of blood  

● function of red blood cells: transport gases - oxygen and carbon dioxide  ● Note: what happens when they are damaged? they are removed from circulation.  ○ they have little ability to heal itself because it doesn’t produce proteins for  cellular repair  

life cycle:

1. red blood cells formed in red bone marrow  

2. life cycle is 120 days  

3. after 120 days they are phagocytized (eaten) by liver or spleen  4. in the liver, the heme components of blood are recycled:  

a. globin portion is broken down and the amino acids are utilized. iron keep,  but heme is eliminated through bile.  

b. iron is transferred and store by the protein ferritin in the livery  

i. iron in free state is toxic. it needs to be bound to transport protein -  taken to liver if not already there- and bound to ferritin (protein in  

liver than stores iron for us)  

ii. iron is absorbed easier from food, rather than supplement.  

c. heme (without iron) is converted into biliverdin and then to bilirubin, which  is secreted in bite from the liver  

5. the erythrocyte membrane proteins and globulin proteins are broken down into  amino acids, and some of these components are used to make new erythrocytes  6. What organ keeps the red blood cell numbers relatively constant?  a. the kidney (produces erythropoietin) is in charge of looking at the balance  of oxygen in the erythrocytes by looking at the oxygen content. it doesn’t

count erythrocytes, it just looks at oxygen content. if correct oxygen  content , then correct red blood cell number.  

Hemoglobin:  

1. What is hemoglobin made up of? 2 alpha and 2 beta amino acid chains  2. what is in the center of hemoglobin? a heme group  

3. what is located within a heme group? iron atom  

4. what does bright red color pigmentation of blood indicate? That  it contains oxyhemoglobin- a lot of oxygen → bright red color  5. what does a darker red pigmentation of blood indicate? That it  is deoxyhemoglobin - little oxygen → darker red color 6. What is carbaminohemoglobin? A hemoglobin structure where carbon dioxide  binds to molecule but does not compete for heme with oxygen, the carbon  dioxide binds to the amino acid portion of globin protein  

7. Why is it important that hemoglobin is packaged within erythrocytes? The  packing protects the molecule from breaking into fragments, and an erythrocyte  is a transport vesicle that carries 200 hemoglobin molecules. The packing  contributes to blood viscosity and osmotic pressure.  

Leukocytes:  

1. What are the two types of leukocytes? granulocytes and agranulocytes  2. What do all leukocytes have in common? They are mobile, flexible, found in  blood vessels and body tissues, helps in body defense, and presents a small  percentage of total blood volume (less than 1%).  

3. What is a granulocyte? A leukocyte with granules present.  

4. What are the 3 types of granulocytes? neutrophils, eosinophils, and basophils  5. What is an agranulocyte? A leukocyte without granules.  

6. What are the 2 types of agranulocytes? monocytes and lymphocytes.  7. What are the two reasons a leukocyte leaves the bloodstream? Diapedesis and  amoeboid motion

8. What is diapedesis? passage of blood cells through intact vessel walls into tissue  9. what is amoeboid motion? the flowing movement of the cytoplasm of the  cell/phagocyte  

10. What triggers leukocytes to leave blood circulation? The infection site releases  signaling molecules to attract leukocytes to the specific site.  

11. What are the signaling molecules? Positive chemotaxis.  

12. What do the positive chemotaxis do to get the leukocyte attention? Lay down a chemical trail to lead leukocytes to infection  

13. What other molecule type does the infection site use to attract leukocytes?  Adhesion molecules are used at entrance of infection site to inform leukocytes of  where to dive out of the blood vessel.  

Granulocytes:  

1. What is the common shape of nuclei among all 3 granulocytes? They have a  lobed nuclei within their spherical cell shape.  

2. What is the functional purpose of granulocytes? Phagocytize  

3. How do neutrophils operate? Like Kamikaze pilots (if needed, they are willing to  go in and bust open to release oxidizing substances to kill self, but also kill the  nearby intruder as well).  

4. What do neutrophils contain? Fine granules that are filled with lysosomal  enzymes or antibiotic-like proteins (defensins)  

5. What type of burst do neutrophils undergo? Respiratory bursts- involves the  formation of oxidizing substances  

6. How do the eosinophils operate? Like P52 bombers- they drop granules then  take care of large parasitic worms that are too large to be phagocytized.  7. Aside from helping destroy parasitic worms, what else are eosinophils associated  with? Allergic reactions- they phagocytize immune complexes associated with  allergies and release chemicals that inactivate inflammatory chemicals.  8. What type of granules do basophils have? Histamine and Heparin

9. What is histamine linked to? Edema/swelling through vasodilation (advantageous  when treating an infection site). Histamines are positive hemostatic agents that  can recruit neutrophils.  

10. What is heparin linked to? Anticoagulation - prevents blood clots from forming so  that the injury site continues to have blood flow  

Agranulocytes:  

1. Comparing granulocytes to agranulocytes, which is larger? agranulocytes  2. What are the two types of agranulocytes? Lymphocytes and monocytes  3. Where are lymphocytes mainly located? Lymphoid tissue (few in circulation)  4. How much of the cell does the nucleus occupy? Majority - cytoplasm is in outer  edge. Nucleus is very large.  

5. What are the 3 “flavors” of lymphocytes? T cells, B cells, and Natural killer cells.  6. What is the function of T cells? T cells aim to destroy virus-infected cells & tumor  cells (basically any antigens found within a cell)  

7. What is the function of B cells? B cells give rise to plasma cells that produce &  release antibodies when it notices any antigens found outside the cell. these are  part of specific immune system.  

8. What is the function of Natural killer cells? Natural killer cells attack abnormal  and infected tissue cells because they are nonspecific. Thus, they target anything  that shouldn’t be there. Basically, if they see foreign then they kill.  

9. What is distinctive about a monocyte (size wise)? It’s the largest WBC 10. What do monocytes differentiate into? macrophages  

11. What are the functions the macrophage monocyte? Activate lymphocytes to  mount immune responses and assist lymphocytes (mostly T and B cells)  12. What is the structural characteristic of the monocyte nucleus? the nucleus is  kidney-bean shaped.  

Platelets:

1. How do platelets arise? When megakaryocytes in the bone marrow break off  from large cells, it creates cell fragments that are known as platelets.  2. What is unique about the nucleus of a platelet? They are multinucleated because  they undergo many mitotic divisions but never undergo cytokinesis.  3. What is the structural characteristics of platelets? Platelets are simply plasma  membranes “packets” of cytoplasm that have granules (that have many  chemicals).  

4. What is the function of platelets? Helps with blood coagulation (blood clots),  hemostasis, and blood thrombus formation.  

5. What is a thrombus? A thrombus is a clot that forms in an unbroken blood vessel.  

Hemopoiesis:  

1. what is hemopoiesis? the production of formed blood cell formation  2. what does hematopoiesis occur? red bone marrow  

3. From what type of cell do all formed elements arise from? A single population of  stem cells (hemocytoblasts)  

4. Myoblasts differentiate into what two types of lines? Lymphoid stem cell line and  myeloid stem cell line.  

5. What is the lymphoid stem cell line? The lymphoid stem cell line makes only  lymphocytes - so B cells, T cells and natural killer cells.  

6. What is the myeloid stem cell line? The myeloid stem cell line makes  erythrocytes, thrombocytes (platelets), eosinophil, basophil, neutrophil,&  monocyte  

7. How are the two stem cell lines regulated? Two domains: erythropoiesis and  thrombopoiesis  

8. What is erythropoiesis regulated by? erythropoietin  

9. What is thrombopoiesis regulated by? thrombopoietin  

Chapter 20 Notes:

The Endocrine System:  

● a system of ductless glands that work together along with the Nervous System to  coordinate and integrate the activities of the body’s cells. Thus, regulating body  functions.  

Endocrine System Nervous System

Communication Method: Hormones Neurotransmitters targets: Cells with receptors specific response time & effect slow. metabolic activities rapid. contraction/secretion range of effect widespread; general localized; specific response duration long-lasting short term recovery time slow rapid; immediate

Endocrine = ductless glands  

● the cells release the product into  

interstitial fluid (blood or lymph)  

● chemical messengers= hormones

Endocrine system organs:  

● Organs are small and not as valued as other organs

○ example: pituitary- size of pinky but it has a large impact on body ○ Other endocrine organs:  

■ Pituitary (anterior and posterior)  

■ pineal gland

■ thyroid

■ parathyroid gland

■ adrenal gland  

Endocrine system- does not display anatomical continuity- organs are scattered  throughout the body  

Target organs -

● comprised of target cells

● has receptors that hormone binds to and affects

○ can cause wide variety of responses:  

■ mobilization, maintaining water levels, growth and development,  regulation of cellular metabolism and energy balance

Endocrinology- study of ductless glands, the hormonal products, and how they affect  target organs  

Hormones are classified based on their chemical structure:  

Hormone Type Chemical Structure

peptide hormones: chains of amino acids

hormones that have amino acid  derivatives

biogenic amines

steroid hormones derived from lipids fatty acid-derived hormones eicosanoids  

eicosanoids - are signaling molecules made by oxidation of 20-carbon fatty acids.

Hormone Regulation through Feedback Loops

1. Negative Feedback loop:  

a. most common  

b. there is an OPPOSITE directional change.  

c. the system causes a decrease/end to original stimulus  

d. example: Human body temperature  

i. The hypothalamus of a human responds to temperature  

fluctuations and responds accordingly.  

ii. If the temperature drops, the body shivers to bring up the  temperature  

iii. If it is too warm, the body will sweat to cool down due to  evaporation.

1. Stimulus = eating food causes a rise in blood glucose levels  2. The insulin-secreting cells of pancreas detect high blood glucose levels.  3. Pancreas secretes hormone: insulin  

4. insulin causes liver cells to take up glucose and store it as glycogen  5. as body cells and liver take up blood glucose, glucose levels decrease  and the insulin being released stops  

6. body is now returned to homeostatic blood glucose level  

2. Positive Feedback loop:  

a. same directional change  

b. the system causes an increase or exaggerated response over the original  signal.  

c. output is increased  

d. usually the control is episodic or infrequent - meaning they do not require  continuous adjustments  

e. An example of a positive feedback mechanism is blood clotting.  i. Once a vessel is damaged, platelets start to cling to the injured site  and release chemicals that attract more platelets.

ii. The platelets continue to pile up and release chemicals until a clot  is formed.  

Summary: Positive feedback mechanisms enhance the original stimulus and negative  feedback mechanisms inhibit it.  

Hypothalamic Control of Endocrine System:  

● “master control” of endocrine system because it oversees most activities, but  NOT ALL endocrine glands/structure are controlled by hypothalamus.  ● However, the activity that is controlled is done via the pituitary gland  ● Hypothalamus is responsible for:  

1. producing regulatory hormones stimulate or inhibit anterior pituitary  hormone secretion.  

2. produces hormones that are stored and released from posterior pituitary  a. hormones = antidiuretic + oxytocin  

3. stimulates hormone secretion of adrenal medulla via sympathetic  innervation  

a. hypothalamus is overseer of autonomic nervous system  

Pituitary Gland (Hypophysis)

● located below the hypothalamus  

● structurally and functionally divided:  

○ anterior pituitary “adenohypophysis”

○ posterior pituitary “neurohypophysis”

● this gland is derived from embryonic structures

Hormones secreted from the anterior pituitary

Hormone: tropic? Secreted by: Acts on:  

Thyroid-stimulating  

hormone (TSH) ✓

thyrotropic cells thyroid gland to  release thyroid  

hormone

prolactin (PRL) mammotropic cells mammary glands  to stimulate milk  

production

adrenocorticotropic  hormone (ACTH)

✓ corticotropic cells adrenal cortex to  cause release of  

corticosteroids  

growth hormone (GH) ✓ somatotropic cells all body tissues to  grow (esp. bone,  

muscle, adipose  

CT)

follicle-stimulating  hormone (FSH) &  

luteinizing hormone (LH)

✓ gonadotropic cells gonads  (testes/ovaries) to  

stimulate  

development of  

gametes  

(sperm/oocyte)

melanocyte-stimulating  hormone (MSH)

pars intermedia cells (in  anterior pituitary)  

melanocytes in  epidermis to  

stimulate melanin  synthesis

Tropic hormones are hormones that have other endocrine glands as their target. Most  tropic hormones are produced and secreted by the anterior pituitary.

Control of Anterior Pituitary Secretions:  

→ Hypothalamo-Hypophyseal Portal System

● is a system of blood vessels in the brain that connects the hypothalamus  with the anterior pituitary.  

● function = transport and exchange of hormones to allow a fast  communication between both glands.  

● The fenestrated structure of capillaries in the hypophyseal portal system  facilitates a rapid exchange between the hypothalamus and the pituitary,  with only a small amount of hormones needed to stimulate an accurate  effect in the respective target organs in the body.  

● Fenestrated capillaries have pores in the endothelial cells that are  spanned by a diaphragm of radially oriented fibrils and allow small  molecules and limited amounts of protein to diffuse.

Posterior Pituitary:  

● aka Neurohypophysis  

● does NOT produce any hormones!  

● made up of Pituicytes (main cell type of posterior pituitary gland)  ● has hypothalamo hypophyseal tract

○ a tract of nerves connecting the hypothalamus and the posterior pituitary

Adenohypophysis= anterior pituitary gland

neurohypophysis= posterior pituitary gland

Thyroid Gland

● located: in neck  

○ inferior to larynx  

○ anterior to trachea  

● surrounded by capsule made from connective tissue  ● has two lobes (left and right)  

● isthmus connects the left and right lobe  

● composed of follicle cells (simple cuboidal epithelium)  ○ follicle cells surrounded by central lumen  

○ filled with viscous fluid that is rich in protein = colloid  ○ follicle cells produce thyroid hormones

○ colloid stores the thyroid hormones  

■ note: this is the only hormone that is made “in advance” and store  extracellularly  

● parafollicular cells: produce calcitonin  

○ located in clusters between follicle cells or individually  

● Negative Feedback inhibition of releasing thyroid hormone:  

1. stimulus (low body temperature)  

2. hypothalamus then secretes thyrotropin-releasing hormone  (TRH) → anterior pituitary

3. the thyrotropic cells in anterior pituitary then release thyroid-stimulating  hormone (TSH)  

4. TSH stimulates follicular cells of thyroid gland to release thyroid hormone  (TH)  

5. TH stimulates target cells to increase metabolic  

activities → to increase basal body temperature

6. hypothalamus detects increased temperature → inhibits  secretion of TRH

a. so TH blocks the interactions of TRH from hypothalamus to anterior  pituitary so that formation of TSH is prevented.  

Parathyroid gland:

● located: on the posterior surface of thyroid - wraps around the backside  ● function: produces parathyroid hormone (PTH)  

● Operates by:  

1. parathyroid gland detects low blood calcium levels →  secrets PTH in bloodstream

2. target organs respond to PTH → causes increase of blood

calcium levels

a. this is done by osteoclasts releasing calcium because they resorb  bone connective tissue  

b. also: intestine increases absorption of calcium (with help from  calcitriol)  

3. rising calcium levels in blood prevents release of PTH into bloodstream  ● calcitriol promotes calcium absorption  

Parathyroid ^ Thyroid^

Adrenal Glands:  

● pyramid shaped  

● paired  

● superior to each kidney  

● retroperitoneal- behind the peritoneal  

● no ligaments to attach them - so they are held in place by fat and strategically  placed fascia to minimize movement  

● it is very well vascularized - (common features with endocrine organs)

● two regions: cortex and medulla  

(structurally different - like how the anterior  

and posterior pituitary are different)  

○ cortex- outer region  

■ has 3 layers  

● zone glomerulosa

balls of cell  

● zone fasciculata - stacks of cells  

● zone reticularis- cluster of cells

■ and produces corticosteroids  

● which are important for life - regulate nutrients, water,  

sodium  

● we need to know: do you know where GH is from? and what  it’s basic function is?  

○ medulla- inner region  

■ looks more like nervous tissue  

■ chromaffin cells- modified postganglionic cells of somatic NS (so  modified neurons)  

■ releases biogenic amines into blood circulation and has fairly good  halflife  

■ produce epinephrine and norepinephrine  

● they have longevity, and different functionality.  

● epinephrine & norepinephrine- are hormones that are  

secreted by populations of chromaffin cells (when stimulated  

by the sympathetic division of the autonomic nervous  

system)  

○ because hormones are released more slowly than  

nerve impulses and their effects are longer lasting,  

the secretion of these hormones help prolong the  

effects of the sympathetic stimulation. so the

sympathetic responses continue to linger because  

these hormones are still present in the bloodstream to  

still affect their target cells.  

○ they are structurally and functionally different because of where these  parts arose from during embryonic development  

Histology slide : book explains this Table 20.6  

● usually you see cortex- medulla- cortex in slides  

● Zone Glomerulosa- balls of cells  

○ produces: mineralocorticoids  

■ the main mineralocorticoid is aldosterone- regulates sodium  

● so it also regulates water  

● Zone Fasciculata  

○ produces glucocorticoids  

■ main glucocorticoid is cortisol - regulates glucose in blood  

■ and plays a role in lipid and protein metabolism  

● Zone Reticularis: clusters of cells  

○ produces gonadocorticoids  

■ minor role in adults  

■ the time they really have a big influence is in puberty - important  they make a transition at the time of puberty  

■ can be androgens and estrogens  

^^ these are all types of corticosteroids= hormones important for survival of the  organism

● important because they regulate important things: water, sodium ,  nutrients, reproduction  

Pancreas

● heterocrine organ - but majority of function is exocrine , like 1% of mass is  endocrine function  

● endocrine function in pancreatic islet:  

○ main endocrine cells found here:  

■ alpha cells- glucagon  

● works to regulate blood glucose levels (increases levels of  

blood glucose)  

■ beta cells- insulin  

● works antagonistically with glucagon to regulate blood  

glucose levels (decreases blood glucose levels)  

■ delta cells - somatostatin  

● somatostatin from islets helps to regulate the alpha and beta  

cells - so it indirectly regulates the blood glucose levels  

■ F cells - pancreatic peptide  

● this is an interesting hormone that acts locally - it helps to  

digest the digestive processes occurring in the GI tract  

○ with all these hormones we are growing, regulating, and digesting  ■ basically directing nutrient processes  

Pineal Gland

● located in part of the diencephalon - near the epithalamus  

● composed of: pinealocytes  

● also called “brain sand” - small grains of calcareous material . a sign of aging.  ○ older people have more sand  

○ you can use pineal gland to map where you are in the brain because the  sand is easily seen  

● produces melatonin -hormone that is cue for night  

○ cyclic release  

■ increases at night, decreases during the day  

○ cue for night

■ produces melatonin when no or little light. when light is present - it’s  shut down  

Thymus

● makes hormones but they don’t travel outside the thymus

● what: fatty structure  

● located: superior to heart, posterior to sternum, within the mediastinum  ● it’s a bilobed structure

● large in infants, but regresses with age (puberty is marker here)  ○ this transition is noted by functional tissue of thymus replaced with fat and  fibrous CT so it become inactive in function  

● function: regulate and modulate body immunity  

○ lymphatic system  

● has thymopoietin and thymosin stimulate and promote differentiation, growth,  and maturation of lymphocytes (T cells)  

○ lymphocytes arrive in bone marrow, and then go to thymus to get  “educated” into T cells  

○ so this is why diseases like AIDS are bad- it causes you to lose T cells.  ■ so once you lose T cells, you can’t get them back.  

Gonads

● produce steroidal sex hormones  

● controlled by gonadotropins (FSH & LH)  

○ ovaries  

■ hormones produced by ovaries: estrogens and progestins  

● select cells of ovarian follicle produce these in the ovaries  

○ testes  

■ produces: androgens-  

● produced by Leydig cells (interstitial cells) of testes

○ testosterone is most prominent of androgens  

■ produces inhibin produced by Sertoli cell (sustentacular cells)  

● inhibit GnRH release by hypothalamus  

- gonadotropin releasing hormones (GnRH)  

Non-Endocrine Organs - have endocrine functions

● heart-  

○ produces atrial natriuretic factor (ANF) “atriopeptin”  

○ produced by atrial muscle cells & released in response to elevation in  blood pressure

● Gastrointestinal tract  

○ Variety of hormones released from enteroendocrine cells, which are found  throughout GI tract

■ primary function to regulate digestive processes

● kidney-  

○ produces two hormones:  

■ Erythropoietin - signal bone marrow to increase red blood cell  

production  

■ Renin- initiate the Renin-Angiotensin system & stimulates thirst and  elevation of bp  

● renin is an enzyme!  

● renin does not actually do this, it just starts the cascading of  

events  

● skin  

○ cholecalciferol  

■ this is the precursor molecule that allows skin to produce vitamin D  from sunlight by changing the structure  

■ released into circulation and activated in kidney (calcitriol)  

● adipose tissue  

○ leptin- peptide hormone

■ appetite control / the feeling of “fullness”  

■ so pumping people with these hormones alone doesn’t make them  feel full - more complicated than that  

○ resistin- peptide hormone  

■ linked to high levels of ȩbadȪ cholesterol → which  increases risk of heart disease

Endocrinopathies- any disease resulting from a disorder of an endocrine gland or  glands  

● caused by:  

○ too much hormone (hypersecretion)  

○ too little hormone (hyposecretion)  

○ receptor isn’t working (receptor dysfunction so they won’t respond)