Description
Ch. 20: The Endocrine System
1. The endocrine system is one of the 2 controlling systems of the body. It acts with the NS to coordinate and integrate the activities of the body’s cells thus regulating body functions. With that being said, what do the NS and endocrine system do as they work together? They bring about homeostasis.
2. What are the differences between ES and NS?
ES uses H’s for communicating and NS uses Neurotransmitters. ES targets cells with R’s for H’s and Ns targets specific targets. ES response time and effect for is slow metabolic activity while the NS is rapid for secretion/contraction. The range of effect for ES is widespread and for NS it is localized and specific. The response duration for ES is long lasting and Ns is short term. The recovery time for ES is slow and for SN it is rapid and immediate.
3. Why do we cry when we feeling strongly about something?
The limbic system is responsible for this and is connected to the hypothalamus and hardwired to the ANS, which responds by a neurotransmitter called Ach and has a degree of control over the lacrimal tear system and it is a tiny molecule, which then stimulates tears.
4. Where are H’s secreted into?
It is secreted into the blood/lymph by endocrine glands or organs (ductless glands) 5. What do H’s affect?
It affects target organs comprised of target cells which present R’s for the H to bind to on the cell surface.
6. What are major processes controlled by H’s?
Growth and development, reproduction, mobilization of body defenses, maintenance of electrolytes, water and nutrient balance in blood, regulation of cellular metabolism and energy metabolism.
If you want to learn more check out During which stage of the cell cycle does sister chromatids separate?
7. What is endocrinology?
Study of ductless glands, their H products and effect on target organs.
8. How are H’s classified?
peptide hormones--chains of amino acids / vary in size greatly / many are glycosylated many H’s of the body found in this classification
amino acid derivatives-- biogenic amines, TH’s
steroid hormones-- derived from the lipid, cholesterol
fatty acid-derived hormones-- eicosanoids
9. What does the structure of a H dictate?
How it interacts with the target cell with a R or a target organ. R’s are found in 2 locations…either the plasma membrane or intracellular.
10. How do H’s regulate themselves and what are the 2 different kind of feedback loops? They regulate themselves by feedback loops.
The negative feedback loop is the most common, it is opposite directional change, the output of system causes a decrease or shuts off the original stimulus. It keep the variation minimal.
The positive feedback loop is the same directional change. The enhance/exaggerate the response over the original stimulus, thus the output is increased. It usually controls episodic or infrequent events that don’t require continuous adjustments. Limited due to proceeds with the very little control. Don't forget about the age old question of What is the nature of energy?
11. What is the hypothalamus’s responsibilities in the endocrine system? It is considered he master control center of the ES and oversees most endocrine activity by the pituitary gland. It impacts the endocrine system by releasing regulatory H’s from the AP, it produces ADH and oxytocin through the PP and lastly, secretion from the adrenal medulla by the ANS
12. What is another name for the pituitary gland?
Hypophysis
13. What are the H’s of the AP?
The check mark means that the H is tropic, which means it is under influence of the hypothalamus. (there isn’t a check mark in the picture…so these are the tropic H’s: TSH, PRL, ACTH, GH, FSH and LH)
14. Discuss the anterior pituitary: It is called the adenohyphysis and it is where the H’s are made and secreted. Don't forget about the age old question of What is the time constant?
15. What is the hypothalamo hypophyseal portal system?
It is a vasculature portal. It serves as a shunt to move from the hypothalamus to the anterior pituitary. H’s are released and picked up by the primary plexus and shunted to the capillary bed called the secondary plexus, which goes to the AP.
The Hypothalamo-Hypophyseal Portal System: It is a vasculature portal. It serves as a shunt to move from the hypothalamus to the anterior pituitary. H’s are released and picked up by the primary plexus and shunted to the capillary bed called the secondary plexus, which goes to the AP.
The portal vein is a group of vessels that links 2 capillary networks. The gonadotropin H leaves the hypothalamus to go to the pituitary gland. It releases follicle stimulating H (oogenesis and spermogenesis) and luteinizing H. the corticotropin releasing H releases adrenalcortico H. the adrenal cortex releases cortisol. Thyroid releasing H lets out the thyroid stimulating H from the hypothalamus to the AP. This whole system collects blood from the capillaries originating in the hypothalamus and through a plexus of veins surrounding the pituitary stalk, it direct the blood in the AP gland. This allows the neuroH’s secreted by the neuroendocrine. If you want to learn more check out Bilateral contract means what?
16. What is the PP called and discuss some characteristics of it:
It is called the neurohypophysis. It does not produce any H’s. it is made up of pituicytes that are like glial cells and their function is to regulate the release from the posterior from neurosecretory cells from the hypothalamus. We also discuss several other topics like In agriculture, what is commercial and industrial settings?
The Paraventricular nucleus—produces ocytocin (stimulates smooth muscle contraction.) The supraoptic nucleus—produces ADH (assists with water retention) 17. What are thyroid follicles?
parafollicular cells produce calcitonin, or CT, located in clusters between follicles or individually. The follicle walls are composed of simple cuboidal epithelium – follicle cells, which surround a central lumen filled with a viscous, protein-rich fluid called colloid; follicle cells produce TH’s that are stored in colloid – only hormone that is made “in advance” & stored extracellularly If you want to learn more check out What is the core inflation?
18. What is the function of the thyroid gland? It stimulates low body temp. How does this happen? (hint: know this mechanism in the picture!!!!!!)
19. What is the parathyroid gland made up of and what do they secrete?
Chief cells—PTH H / oxyphil cells are larger and unknown cell type that doesn’t produce H’s
20. PTH regulates blood Ca levels… what is this pathway??
21. What is the adrenal gland comprised of?
Structurally comprised of an outer, cortex and inner, medulla, which are structurally as well as functionally different. The adrenal cortex secretes corticosteroids and the medulla secretes the biogenic amines
22. What are endocrinopathies? What causes them?
ENDOCRINOPATHIES (disease resulting from disorder of an endocrine gland or glands)
Too much H (hypersecretion), too little (hyposecretion) and lastly, R is not working. 23. Explain the layers in the picture below
Shape: cross section—cortex-medulla-cortex
Zona G????Balls of cell—mineralocortocoids—eldosterone regulates Na, therefore regulating water.
Zona F????glucosecortocoids—cortisole regulates glucose levels and plays a role with lipid and protein metabolism (amino acids and fatty acids). (regulates nutrients!!!)
Zona R????gonadocortocoids: they influence puberty—anogenes and estrogenes (can be either or)
These are all cortocoidsteriods—H that are important for survival of organisms—sodium, water and nutrients and reproduction
Medulla is made up of chromaffin cells—modified postganglions of SNS. Epinephrine in a neural pathway are diff. than the ones that are in the blood. (Interesting element…b/c this refers to longevity.) Medulla has them out in the blood circulation and they have a good half life.
chromaffin cells, modified ganglionic cells of SNS; produce epinephrine & norepinephrine
24. Why is the pancreas a heterocrine organ?
Endocrine and exocrine functionalities, but mostly exocrine (helps with digesting) 25. What are in the pancreatic islets?
alpha cells – glucagon—antagonistic cells that regulate glucose.
beta cells – insulin
delta cells – somatostatin– helps regulate alpha and beta cells.
F cells – pancreatic peptide– H that acts locally / regulates digestive processes in the GI tract which is next door.
26. What is the function of the pineal gland? It is comprised of pinelaocytes and produces melatonin for a que for night. When light is present it is shut down and sand is a sign of aging.
27. Why cant t cells be replaced in adults?
The thymus is only active in infants and regresses with age = inactive.
28. Function of the thymus?
Regulate & modulate body immunity—thymopoetin and thymuses stimulate and promote differentiation and growth and maturation of lymphocytes. It becomes T cells. Lymphatic system
29. What are gonads controlled by?
Follicle stimulating H and luteinizing. In the ovaries the estrogens & progestins, produced by select cells of ovarian follicle. In the testes androgens, produced by Leydig cells (interstitial cells) of testes????testosterone most prominent
H: inhibin produced by Sertoli cell (sustentacular cells)????inhibit Gonadaltropin releasing H release by hypothalamus
30. What are the functions of non-endocrine organs?
Heart
a. Atrial natriuretic factor (ANF) or atriopeptin
i. produced by atrial muscle cells & released in response to elevation in
blood pressure
Gastrointestinal Tract
b. Variety of hormones released from enteroendocrine cells, which are found throughout GI tract
i. function to regulate digestive processes
Kidney
c. Erythropoietin (EPO)
i. signals bone marrow to increase RBC production
d. Renin –this is an enzyme but releases as a chemical messenger.
i. release by specialized cells to initiate the Renin-Angiotensin system/for blood pressure; also stimulate thirst & elevation of Blood Pressure.
ii. Renin starts the cascade of events.
Skin
e. Cholecalciferol
i. released into circulation and activated in kidney (calcitriol)—active form of vitamin D3
Adipose tissue
f. Leptin—appetite control/feeling of coolness & Resistin-insulin antagonist, peptide hormones
Chapter 28 the Reproductive System
31. How is the zygote formed? The testis and ovaries? The accessory sex organs? Formation of the zygote
At puberty cells in the gonads (testis or ovaries) undergo meiosis. 23 pairs of homologous chromosomes become 23 chromosomes. The germ cell from the male (sperm) will then fuse with the germ cell of the female (ovum) during reproduction to reform a cell with 23 pairs of homologous chromosomes.
The sex of the zygote is determined by the sex chromosome of the fertilizing sperm. Formation of Testis and Ovaries
After conception the embryonic gonads of males and females are similar (for about the first 40 days). Therefore the embryo can form either testes or ovaries. The presence or absence of the Y chromosome determines what happens. SRY (sex determining region of the Y chromosome) on the Y chromosome male. SRY gene encodes the testi-determining factor.
Accessory Sex organs:
For the first 40 days the reproductive system of the embryo is undifferentiated and has accessory organs characteristic of either sex.
32. Discuss the difference between male and female characteristics:
Male: Wolffian ducts, epididymis, ductus (vas deferens), seminal vesicles, ejaculatory duct.
Sertoli cells: Mullerian inhibitory factor (MIF): regression of the Mullerian ducts Leydig cells: Testosterone: epididymis, ductus (vas) deferens, seminal vesicles, ejaculatory duct.
Female: Mullerian ducts, uterus, fallopian tubes
External Genitalia
External genitalia of males and females are identical for the first 60 days. 33. Why is the male reproductive system a continuous system? It goes from one place to another.
34. Functions of the male reproductive system? It produces gametes, functional maturation, nourishment, storage and transport and steroid productions.
35. Where do the testis form? Near the kidneys
36. What is the gubernaculum? It is a bundle of CT that extends from the testis to the floor of the scrotal sac. The growth continues and it doesn’t change in length, which is why we tug on the testis. The fetus grows rapidly at 7 months and there is a release in growth and H’s which makes it contract and form the tunica vaginalis (serous membrane). This allows the movement in the scrotum sac. The ductus deferens, blood vessels, nerves and lymphatic vessels are also brought down. This forms the spermatic cord. Then, the inguinal canal is sealed up.
37. What is the outer portion of the testis? Tunica vaginalis—it has parietal and visceral parts that allow movement.
38. What is the tunica aldriginia? This is what the testis is wrapped in. the CT invaginates into the testis proper, forming the septa, which then forms the globules. These are responsible for housing the somniferous tubules.
39. What occurs in the somniferous tubules? Spermatogenesis. This is the becoming of a structurally mature sperm cell. It occurs in the lumen of the s. tubules. 40. What is found in the mediastinum testis? Rete testis—this forms a network and leaves the testis through the efferent ductules. It is like a site of entry for the testis proper.
41. What is housed in the spermatic cord? What isn’t found in here? Nerve and vasculature. No lymphatics.
42. Discuss the relationship between the testis and the scrotum and the spermatic cord: cremaster muscle—sk muscle that is found in the scrotal wall. It raises or lowers the testis. The dartos muscle—smooth muscle, found in the scrotal wall, important for temp regulation. It causes the wrinkles of the scrotum. Raphe—line of union b/w 2 continuous structure. Panpiniform plexus—it is the spermatic cord. It is the counter current mechanism and helps with heat exchange (blood that enters the testis is cool and leaves is heated). It is wrapped by testicular veins where it becomes a plexus. This is how the testis temp is regulated.
43. What is spermatogenesis? Where does it take place? What happens? It occurs in the s. tubules. It is the making of sperm. It takes around 70 days to make. It goes through meiosis.
44. What is significant about the blood testis barrier? It is a tight junction b/w sertoli cells called nurse cels. The sperm is developed in b/w the sperm and protects the sperm. This is here so it can isolate sperm cells that are developing. This is needed in males that recognize spermatogonia but it doesn’t recognize a primary or secondary spermatocyte, spermatids and structurally mature sperm. This keeps the area isolated bc the surface antigens change and become nonself.
45. What is spermiogenesis? Reconstructuring of the round part of the spermatocyte to the structurally mature sperm.
46. What do structurally mature sperm have? Flagella and genetic material. 47. What is spermiation? Sperm loses attachment to sertoli cells.
48. What is the epididymis? What is the function? What are the layers? It lays on the testis and looks like a little moon. It consists of the caput, corpus and the cauda—where it stores ejaculation. It is coiled. The functions include monitoring and adjusting the fluid composition of the sperm cells and recycling damaged sperm. It stores, protects and facilitates functional maturation of sperm. The movement along it occurs peristaltic contractions of the smooth muscle.
49. What do the sperm learn when they enter epididymis? Swim and capacity to fertilize. 50. What is the ductus deferens? It connects the epididymis to the urethra. It is ciliated columnar epithelium.
51. What is the ejaculatory duct? Joining of the ampulla and the seminal vesicles. 52. What does the urethra do? Delivers the gametes into the female reproductive system 53. Purpose of the accessory glands? It provides fluid components of semen and is a mixture
of various glands. It provides nutrients and functional maturation and a buffer. 54. What are the seminal vesicles? It makes a lot of the semen and is actively secreting things high in fructose, PG’s and fibrinogen. It is slightly alkaline.
55. What is the prostate gland? And its importance? Encircles the urethra and is smooth muscle. It produces prostatic fluid and contains seminal plasmin which is antibacterial to help keep the skin clean.
56. What is the bulbourethral gland? It is tubulavelar mucous gland that secretes thick, alkaline mucus and gives the fluid composition.
57. What kind of tissue is in the penis? Erectile tissue
58. What is the arterial blood supply made of? Helicine and nutritive
59. What are the 3 tissues of the penis? 2 are the corpus cavernosum—central arteries and the last one is the corpus spongomium which is where the urethra is found. 60. What is erection? Vasodilator impulses from PNS and causes the relaxation of penile vessels.
61. What is ejaculation? Coordinates by SNS / ejecting semen in the body 62. Which H stimulated leydig cells and what do these cells do? LH. These cells produce testosterone.
63. What do PRL do? Increases sensitivity of interstitial cells to LH
64. What H’s does spermatogenesis require? FSH and testosterone
65. What is the role of inhibin? Working as a “sperm barometer”
66. Prolactin in males _____ the sensitivity of LH. Answer: Increases
67. What are the functions of the female reproductive system? Gamete production, steroid production, fertilization, embryonic and fetal development, parturition and nutrition postpartum.
68. Why is the female reproductive system discontinuous? There is a break in the system at the ovaries. When the oocytes are delivers to the oviduct they don’t have to be picked up by it but some go to it and some are found in the organs.
69. Define anteverted and retroverted of the uterus. Anteverted- where the uterus is inclined forward. Retroverted- a women age they become this and the uterus is turned back towards the rectum.
70. What happens in the medulla and the cortex? Medulla—vasculature and lymphatics whereas the cortex has oogenesis happening (where all the action occurs). Premortal follicles go through development until it is a mature follicle????ovulation. The remaining elements of the follicle undergo a morphological change and become a corpus luteum. 71. What is oogenesis? Development of an egg/ovum
72. What are oogonium? Diploid cells that divide through mitosis.
73. What is the difference between males and females? In the males there is the presence of spermatogoniums (stem cell is retained). In female, before birth, the oogonium goes to meiosis and is arrested. The women has her full complement of oocytes. (this is diff. than in males)
74. What is menarche? 1st reproductive cycle after meiosis 1
75. What is menopause? 1 year without a reproductive cycle
76. Why do females produce 1 ovum and males produce 4 structurally mature sperms? Polar bodies get rid of the rest of the females reproductive materials. Having all the elements ready for the first division. The ovum has the proteins, the mRNA and everything that is needed until the nucleus of the embryo can take over. The zygote needs everything that is given to it. This is why the ovum is such a large cell.
77. How long is the ovarian cycle? 21-40 days is the length of the ovarian cycle. 78. What are the 2 phases that occur in the ovarian cycle? Follicular phase and the luteal phase. The luteal phase is constant whereas the follicular phase is variable.
79. What is the follicular phase? It recruits a premortial follicle and regresses through events until a mature (vesicular follicle) or the graafin is made. This is a follicle of the oocyte ready to ovulate. It produces estrogen. Then ovulation occurs. The walls thin and pressure builds, then the oocyte pops out.
80. What causes ovulation? A peak in the gonadotropins. LH is a larger rise in the concentration than FSH. This affects the cells that are left in the follicle. 81. Luteal phase: cells left in the follicle. Follicle has been producing estrogen and undergoes a morphological change and becomes the corpus luteum. Now it produces progesterone. 82. What is maintained during pregnancy when there is a signal being maintained? The corpus luteum is maintained during pregnancy, otherwise it is inactive. 83. What are the oviducts? It is a hollow muscular tube suspended by broad ligament and open into the peritoneum.
84. What are the 3 segments of the oviducts? The infundibulum, ampula and the isthmus. 85. What are the functions of these? The infundibulum is not attached to the ovary but it picks up the oocyte with the fimbrae. The ampulla is where the fertilization occurs and the isthmus connects to uterus and serves as a sperm reservoir. It releases waves of sperm so that it can hang out in the isthmus so the sperm is continuously released. 86. What is the function of the oviducts? It received the oocyte, site of fertilization and preimplatation development (implants in the uterus).
87. What is unique about the implantation of the oocyte in the oviducts? This is where the embryo can implant in the infundibulum and be outside of the organ.
88. What is the uterus? A hollow muscular organ that is held in place by the broad ligament and other ligaments to limit movement.
89. What are the anatomical divisions of the uterus? Fundus- dome shape portion, the body known as the corpus and the cervix-inferior narrow portion that opens into the vagina. 90. What are the functions of the uterus? It is where the site of implantation and embryonic and fetal development happen. It plays a role in parturition. This is where the embryo is nourished and protected.
91. What are the layers of the uterine wall? Endometrium with mucosal lining. It is made up of 2 elements: the stratum functionalis that undergoes changes in response to the hormones in the environment. It makes for a good environment for implanatation and it is the thickest. This is fed by the spiral artery. It has the uterine glands. The stratum basalis is the foundation for the new layer after menses. It is thin and the straight artery feeds this structure. Next, the myometrium is the next layer in the uterine wall. It is a layer of smooth muscles. The perimetrium is a serous layer.
92. What are the 3 phases in the uterine cycle? (think about what is happening in the ovaries) This cycle is known as the menstrual cycle. Menses—day 1. This is the degeneration of the endometrium (fxal layer)—it breaks down in patches b/c of the spiral arteries (NOT THE STRAIGHT ARTERIES). The functional zone is lost and this is called menstruation. The next phase, the proliferative phase: where the basal zone is robust and restores the endometrium. This is supported by estrogens. Remember estrogen fills and progesterone maintains. In the secretory phase we are making the functional zone very robust. It is maintained by progesterone’s.
93. What happens when the hormonal levels crash? Spiral arteries constrict and that leads to mensus making the menstrual cycle reoccur all over again. The straight arteries are not effects (stratum basalius) when the hormones change b/c it isn’t fed by the spiral arteries.
94. What is amenaria? Loss of menstrual cycle b/c the fat content is so low, like in athletes. 95. What is the function of the vagina and external genitalia? Birth canal, passageway for elimination of menstrual fluids and site of semen deposition.
96. What is the structure of the vagina? Rugae. This allows the vagina to stretch without tearing. It is made up of endothelium (don’t stretch) and CT (stretch). The rugae has inner layers that fold into mucosal folds.
97. What is the function of the mammary glands? Produces milk, lactation, modified sweat gland and it is a specialization of the integument. (seen in females…but males can have this too.)
98. What H’s are produced in mammary glands? prolactin stimulates milk production and oxytocin activates the smooth muscle in the breast tissue which helps with milk projection.
99. What is oxytocin referred to? As the cuddle H. it enhances bonding and maternal behaviors. It may be connected to the limbic system. This brings down blood pressure and makes you more relaxed.
100. What is gynecomastia? Ductal system and milk production alveoli (females), in males they only have a ductal system. This is known as man boobs. This happens with an increase in estrogen. It is seen in puberty in males. Overtime the tissues will be reabsorbed and the mammary structures will no longer exist. (remember the zona reticularis of the adrenal cortex produces gonadocorocoids, androgens and progesterone’s.)
Chapter 21: Blood
1. What is the cardiovascular system comprised of? Blood-transport medium, heart-pump, conduit system-network of blood vessels.
2. What primary tissue type does blood fall under? Connective tissue. *will be on exam!!!!! 3. What does blood consist of? Formed elements (cellular components) and plasma (nonliving fluid matrix)
4. What are characteristics of blood? Sticky, metallic color, alkaline, denser and more viscous than water. Temp is higher than body temp. b/c blood can move heat in the system.
5. What are the cellular components made of? Cellular component- 2 domains: erythrocytes (44% of blood)—these are the hematocrit—the number of red blood cells. Buffy coat platelets and white blood cells are found. Plasma—water, proteins and electrolytes, respiratory gases.
6. What are the functions blood preforms? It helps homeostasis by being involved with distribution, regulation and protection.
a. Distribution—transporting things like nutrients, oxygen, enzymes and hormones and removing things from the tissues such as H’s CO2, waste products…ect. b. Regulation-- maintains body temp. and maintains fluid and electrolytes and pH balance.
c. Protection—protects body from carrying diseased microorganisms, foreign substances and tumors such as the cellular components and antibodies. It also prevents blood loss.
7. What is plasma? fluid component in which formed elements/cellular components of blood are suspended
8. What is it made of? Serum
9. What is the difference b/w plasma and serum? Serum is plasma without the clotting factors.
10. What is found in plasma? Water, proteins and electrolytes.
11. What are the most abundant plasma solutes? Plasma proteins!
12. What are the formed elements of the blood? neutrophil, eosinophil, basophil, macrophage, lymphocytes, platelets, erythrocytes
13. What are the formed elements represented by? Erythrocytes, leukocytes and platelets. 14. What is a complete cell? Leukocytes, anucleate cell? Erythrocyte and what is the cellular fragment? Platelet.
15. Where do the formed elements arise from? Red bone marrow
16. Describe the characteristics of erythrocytes: biconcave discs, during development they lose nuclei and most organelles, but it retains cytoskeletal elements.
17. What are the main components of erythrocytes? Pigmented protein, hemoglobins, functional and structural proteins. It contributes to viscosity of the blood. 18. What are the functions of erythrocytes? The primary function is to transport oxygen and carbon dioxide
19. What is the main component of hemoglobin? RBC and it is a quaternary protein that is comprised of a protein called globin which has a heme group and the red pigment in the middle contains the iron atom.
20. What are the different kinds of hemoglobin? Oxyhemoglobin- form of HG with oxygen. deoxyhemoglobin- form of HG without oxygen. Carbaminohemoglobin- IT is a compound of hemoglobin and carbon dioxide, and is one of the forms in which carbon dioxide exists in the blood.
21. What is the purpose of packaging HG in a RBD? It helps the blood stay together and be packaged neatly through viscosity and osmotic pressure. If it was out in circulation it would dissolve and adjust the fluid balance and circulation to the tissues.
22. Why is an erythrocyte biconcave? This allows larger SA/ it allows movement by diffusion. It also permits the stacking of erythrocytes to each other.
23. Why are erythrocytes removed from circulation? It can’s repair proteins or cells, nor can is replace PM.
24. What takes out the erythrocytes? The liver and the spleen
25. How are erythrocytes recycled? The globin portion is broken down and amino acids are utilized. The heme portion gets the iron taken off of it. The iron binds to a transport protein called transparin to move around in the blood and take it to the liver (if it comes from the spleen). It is bound to ferinin, which retains and stores the iron.
26. What is the kidney responsible for in terms of the erythrocytes? It maintains the balance and destruction levels. It does this by monitoring the oxygen content.
27. What is the function of the leukocytes? It is important for body defenses against disease. It plays an important role in inflammatory and immune responses.
28. Where are leukocytes found? They are found in body tissue instead of the bloodstream! 29. What are the classes of leukocytes? Granulocytes- neutrophils, eosinophils and basophils. Agranulocytes- monocytes and lymphocytes
30. What are some of the special functional characteristics of leukocytes? When they circulate in the bloodstream they are used for rapid travel and transport to areas of invasion or injury. If it leaves the blood stream it is called diapedesis (passage of blood cells through intact vessel walls into tissue). It moves through amoeboid motion, which it the flowing movement of the cytoplasm of a phagocyte. It is signaled to leave the blood steam when the endothelial cells display adhesion molecules (these are called selectins) at the site of inflammation.
31. How do the leukocytes know when to leave circulation? The site of injury and infection have signaling molecules that are released and attracts the leukocytes to the site, which is positive chemotaxis.
32. Define positive chemotaxis: signaling molecules cause the endothelial cells to show selectin (adhesion molecules) that snag them.
33. What are neutrophils? Polymorphoneuclear leukocytes that are the most abundant. They contain fine granules that are filled with lysosomal enzymes or antibiotic like proteins called defensins. It displays respiratory burst which involved the formation of oxidizing substances.
34. What are eosinophil’s? These are granules that contain digestive enzymes. These are used in the destruction of parasitic worms that are too big to be phagocytized. It is associated with allergies and release chemicals that inactivate inflammatory chemicals during allergic reactions.
35. What are basophils? These are least abundant and the granules contain histamine and heparin.
36. What are granulocytes function, overall? They function as phagocytes. 37. What are lymphocytes? These are the 2nd most abundant WBC’s. a few are found in circulation, but it is mostly in the lymphoid tissue. It is classified as cell and the nucleus occupies most of the cell with the cytoplasm in the rim. They play an important role in body immune responses. T cells: destroy virus-infected cell and tumor cells. B cells: give rise to plasma cells and produce and release Antibodies. Natural killer cells: attack abnormal and infected tissue cells.
38. What are monocytes? These are the largest WBC’s. they leave circulation and differentiate into macrophages. They are aggressive phagocytes. They activate lymphocytes to mount immune responses.
39. What are platelets? These are cell fragments that break off from large cells in bone marrow called megakaryocytes. They function in blood coagulation, hemostasis and blood thrombus formation.
40. What is hemopoiesis? The production of formed elements.
41. What do all formed elements arise from? Single stem cell population called hemocytoblast
Chapter 22: The heart
1. How does the heart maintain homeostasis? It continuously circulates blood throughout the body by pumping action of the heart.
2. What are the functions of the heart? What assists the heart with these functions? It serves as a pump, it is the center of cardiovascularization. The heart has a unidirectional flow of blood, there is a side by side pump and the blood vessels have developed blood pressure as a mechanisms for the blood to flow through the vessels.
3. What are arteries, veins and capillaries? Arteries- carry blood away from the heart. Veins-carry blood to the heart. Capillaries are the functional unit that is the site of exchange.
4. What is the systemic circuit and the pulmonary circuit responsible for? The systemic flows out to the body and has a longer flow and more resistance. The pulmonary goes to the lungs and doesn’t require as strong as a pump, so it is shorter and less resistance.
5. What is the basic pattern of blood flow? It flows in the right side of the heart (deoxygenated) to the lungs to get oxygenated and then goes to the left side of the heart where it flows out to the systemic tissues.
6. What is the layer of the heart that is known as the “double walled sac”? The pericardium 7. What are the important parts of the pericardium? The fibrous pericardium is loose filling, tough and dense CT layer. It protects the heart and anchors the heart to surrounding
structures and prevents overfilling. I is attached to the serous pericardium. The serous pericardium is known as the serous membrane. It has 2 layers????the parietal and the visceral layer. The parietal lies next to the fibrous and is apart of the surface of the heart. The visceral layer is known as the epicardium and is the inner part of the heart. Lastly,
the pericardial cavity is the slitlike structure between the layers of the serous pericardium. It contains the serous fluid and allows free movement in the sac.
8. What are the layers of the wall of the heart? Epicardium, myocardium and endocardium. 9. Describe the epicardium: It is the visceral layer of the serous pericardium that covers the outer layer of the heart. With age it increases in fat.
10. Describe the myocardium: This is mostly cardiac muscle cells, the bulk of the heart and it is responsible for contractions. It is packages into spiral and circular bundles by crisscrossing CT fibers that assist to link the heart together.
11. Describe the endocardium: This is the inner surface of the heart. The layer of endothelium is over a thin layer of CT. it lines the heart chambers and covers valves. It is continuous with the endothelium of blood vessels in the heart.
12. What are characteristics of cardiac muscle tissue? It has intercalated disks and the nuclei are found in the center.
13. What do the intercalated disks do for the cardiac muscle? These interlock and are consisted of desmosomes that keep it from pulling apart during contraction. There are gap junctions that aid in communication.
14. What is functional syncytium? This is how the cells in cardiac muscle are coupled. It is electrically coupled cells. This allows the cell to act as a single unit. The gap junctions also come into play with acting as a single unit. This allows highly coordinated contractions to occur.
15. What is the importance of loose CT in the cardiac tissue? It forms the matric that forms the intracellular matric b/w the vasculature and the cells. It connects to the fibro skeleton of the heart. It acts as a tendon. It sets up an insertion for the cardiac muscle tissue.
16. Cardiac muscles have sarcomeres with the m lines, a bands….ect, but what is unique about cardiac muscle tissue? They have a lot of mitochondria which gives them high resistance to fatigue. Also, the t tubules are wider and enter once b/c there are no sarcomeres with triads.
17. Where do all the vesicles leave from the heart? The base
18. What is the fibrous skeleton of the heart? It is CT network found b/w the atria and ventricles. It is formed by dense CT.
19. What are the functions of the fibrous skeleton of the heart? It separates the ventricles and atria. It electrically insulates atria from ventricles. It anchors the heart valve with supportive rings. It provides rigid framework that reinforces the myocardium internally and anchors the cardiac muscles.
20. This question is based on the internal anatomy of the heart. I wrote out the facts that you need to know based on what she said in lecture/there is a picture below to help with the visualization of the functions of these structures:
∙ The coronary sinus has the blood returned to circulation in the RA. *she mentioned this a lot in this lecture!
∙ Atrioventricular valves- connective tissue that anchors the heart wall to the chordae tendinaeae that are hooked to the papillary muscles.
∙ Papillary muscles do NOT contract. The ventricle wall contracts and is pulling on the papillary muscle. The papillary muscles are just anchors.
∙ Septomarginal trabecular- structure that makes sure the RV doesn’t come out ∙ Trabecular carnae- ridges and vallies that help the blood flow through the heart. You don’t want the blood to sit b/c it can clot.
∙ Semilunar valve- open and closes depending on how the blood flows
21. What is the difference b/w the left and right sides of the heart? The left is more muscular b/c it feeds the systemic circuit and the right only feeds the pulmonary.
22. Whats the difference b/w the atria and ventricles? The ventricles are bigger b/c the atria is just a primer pump to fill the ventricles.
23. How is the one way flow of the heart accomplished? By the heart valves that open and close in response to the BP.
24. Why are there no valves on the vena cava or the pulmonary veins? The thin wall and low pressure. When the heart contract it compresses and there won’t be backflow. 25. What happens to the ventricles when contraction occurs? The semilunar valves are open and the blood projects through the valves and the Atrioventricular valves are closed so the atria is filled.
26. What is the cardiac cycle? It represents the period of time from the start of one heartbeat to the initiation of the next.
27. What is the conduction system? Efficient pumping of blood through the heart & blood vessels requires precisely coordinated contractions of the heart chambers
28. What is autorythmicity? The heart initiates its own contraction.
29. How are red blood cells delivered to the lungs? Hepatic portal vein
30. How are RBC’s delivered to the spleen? Splenic vein
31. How are the RBC’s delivered to the lungs? Pulmonary arteries
32. What is the cardiac muscle innervated by? ANS through the coronary plexus. It is parasympathetic through the vagus nerve and sympathetic through the cardiac nerve. 33. What initiates contraction of the heart? SA node
34. How does the parasympathetic decrease HR? it slows down the SA node. 35. What is the heart rate set by in the heart? The conduction system (SA node) 36. What is the coronary circulation of the heart? The heart requires blood supply to function properly. It is the shortest supply of the heart.
37. What do the coronary arteries do? Supply thick and metabolically active cardiac muscle cells of the heart. It supplies the heart with oxygen rich and nutrient rich elements. 38. What allows the heart to have an alternate pathway? Anastomoses
39. Where are the coronary veins from? The coronary sinus. It is an enlarged vessel formed by joining of cardiac veins that empties into the right atrium.
Ch. 23: Blood Vessels
40. Are blood vessels closed or open system? Closed system referred to vascular system 41. What is anastomosis? 2 or more arteries/veins converge, supply same region; provide alternative pathway
42. What is an end artery? 1 pathway by which bld supplied to organ; no anastomoses 43. What is a functional end artery? Small anastom. That limit the alternature pathway 44. What are the 3 types of arteries? Elastic, muscular and arterioles
45. Describe elastic arteries: these have the thickest walls, conducting arteries due to low resistance pathway and conducts bld from heart. Elastic fibers are all throughout the tunics. This has the pressure-smoothing effect.
46. Describe muscular arteries: these are distributing arteries. These deliver and control the blood flow to specific organs. This is the thickness in the tunica media which is involved in vasoconstriction and vasodilation. These are less resilent.
47. What are arterioles? They are found in small and large sizes. They are for vasoconstriction and dilation for minute to minute changes with the environment. 48. What are capillaries? They are the smallest blood vessel. The endothelium surrounded by the loose layer of CT that allows RBS to pass through. There is branching to slow the blood to allow the exchange.
49. What are the basic types of capillaries? Continuous, fenestrates and sinusoids 50. Describe the continuous capillary: most common; located in all vascularized tissue; adjacent cells joined by tight junctions, observe gaps called intercellular clefts, allows limited exchange of fluids & solutes; pinocytotic vesicles also used to ferry fluids across capillary wall
51. Describe fenestrated capillary: similar to continuous but contain pores or fenestrations, covered by a membrane (diaphragm); allows exchange & usually found where active absorption or filtration occur
52. Describe sinusoids: discontinuous capillaries – highly modified, leaky capillaries restricted to certain organs; suited for passage of large molecules & blood cells (large, irregular shaped lumens; fenestrated, few tight junctions, large intercellular clefts); blood flow is slow through these structures
53. Veins are classified into 2 classes of venules and veins. Describe venules and veins: Venules: Form when capillaries merge; vary widely in size & character; can be very porous, allowing fluid & WBC’s to move from bloodstream to tissues
Veins: result from venules merging; display 3 tunics but walls thinner & lumen larger; thin tunica media with tunica externa thickest layer; accommodate large blood volume