Description
EXAM 1 STUDY GUIDE (heart and blood)
Blood
∙ Describe the functions and major components of the circulatory system:
-transport oxygen, wastes, hormones
-protection against blood loss (clotting) and infection (immune system) -regulation of body temperature, pH (buffering), fluid volume
∙ Describe the components and physical properties of blood:
-components
-formed elements (blood cells)
o Erythrocytes-RBC
o Platelets-clotting
o Leukocytes-WBC
-Agranulocytes-lymphocytes, monocytes
-Granulocytes-neutrophils, eosinophils, basophils
-properties
-connective tissue without collagen and elastic fibers
-erythrocytes-heavy
-WBC and platelets-buffy coat
∙ Describe the composition of blood plasma
-serum
-plasma proteins
o Albumins-osmolarity
o Globulins-antibodies
o Fibrinogen/clotting proteins
∙ Describe the structure and function of erythrocytes
-non-nucleated; no organelles
-renew by bone marrow cell division
-flattened discs, biconcave
-carry oxygen from lungs to tissues
-carry carbon dioxide from tissues to lungs
∙ Discuss the structure and function of hemoglobin, as well as its breakdown products
-binds reversibly with oxygen
-4 protein chains
-heme group (contains iron atom)-binds reversibly with one molecule of oxygen If you want to learn more check out jmu microbiology
∙ Explain the basic process of erythropoiesis and its regulation through erythropoietin
-production of red bloods cells
1. Hemopoietic cell transforms into erythrocyte- CFU
2. Erythropoietin (hormone) used to form erythroblast Don't forget about the age old question of this painting medium is opaque, applied to a paper surface, and uses a gum arabic binder.
3. Erythroblasts synthesize hemoglobin rapidly
4. Organelles and nucleus discarded from late erythroblast forming a reticulocyte
5. Cell enters bloodstream and matures into an erythrocyte
-after a drop in RBC count, erythropoietin from kidneys stimulates bone marrow and RBC count goes back up (regulation of erythropoiesis) We also discuss several other topics like respiration i
∙ Describe and discuss causes and symptoms of anemia
-decreased hemoglobin
-decreased hematocrit
o Hemorrhagic anemia- blood loss
o Hemolytic anemia- premature rupture of erythrocytes -abnormal hemoglobin
-pale skin, shortness of breath (tissue hypoxia)
-edema (reduced blood osmolarity)
-reduced BP, increase HR (reduced blood viscosity)
∙ Compare and contrast the relative prevalence and morphological features of the five types of leukocytes
-granulocytes-sphere shaped, globe nuclei
-neutrophils-3-5 lobed nuclei
-eosinophils-2 lobed nuclei with barely visible strand connecting the lobes
-basophils-multi-lobed nuclei covering almost entirety of element
-agranulocytes- lack cytoplasmic granules
-lymphocytes-large spherical nucleus the size of the entire element
-monocytes-kidney shaped nucleus not covering the entirety of the element
∙ Describe the function for each of the five major types of leukocytes
-neutrophils- phagocytize bacteria-release antimicrobial chemicals -eosinophils-phagocytize antigen-antibody complexes-release parasite destroying enzymes If you want to learn more check out onedrive virginia tech
-basophils- secretes histamine and increases blood flow- secretes heparin and prevents clotting and allows WBC mobility
-lymphocytes- destroy cancer cells, viral infections, foreign cells activate other cells of immune system-secrete antibodies-serve in immune memory
-monocytes- differentiate into macrophages-phagocytize pathogens and debris
∙ Discuss the difference in leukopoiesis of granulocytes and agranulocytes
-granulocytes are formed through a myeloid cell line : agranulocytes are formed through a lymphoid cell line -granulocytes involve 1 type of committed cells (myeloblast) : agranulocytes involve 2 types (lymphoblast/ monoblast) -granulocyte precursor cells include promyelocytes, eosinophilic bond cells, basophil bond cells, and neutrophil bond cells : agranulocyte precursor cells include promonocytes, prolymphocytes, T lymphocytes, and B lymphocytes -mature granulocytes are neutrophil, basophil, eosinophils : mature agranulocytes are monocytes, T lymphocytes, B lymphocytes
∙ Explain how platelets differ structurally from the other formed elements of blood
-platelets are cell fragments, so they are more broken than the formed elements of blood
∙ Discuss the role of the megakaryocyte in the formation of platelets
-as blood flows, the cytoplasmic arms of megakaryocytes break off into platelets If you want to learn more check out symmetrical phrasing
∙ Distinguish between the terms hemostasis and coagulation
-hemostasis involves the stopping of the flow of blood (keeping blood inside a damaged blood vessel)
-coagulation is the process in which blood transforms from a liquid state to a solid/semi solid state (step 3 in hemostasis)
∙ Describe the process of hemostasis, including the vascular phase, formation of the platelet plug, and formation of fibrin
Vascular spasm: constriction of blood vessel, increased pressure to decrease blood loss We also discuss several other topics like faulty assumptions in listening
Platelet plug formation: vessel injury exploses collagen fibers of BV vWF bind activated platelets that stick to collagen and each other their granules attract and activate more platelets, and they aggregate to form a “platelet plug”
Formation of fibrin: coagulation factors form prothrombin activator which converts into thrombin-fibrinogen turned into fibrin by thrombin and fibrin glues the platelet plug together
∙ Explain the difference between extrinsic and intrinsic clotting factors
-extrinsic: activated by external trauma that causes blood to escape from the vascular system- quicker than the intrinsic pathway-involves factor VII.
-intrinsic: activated by trauma inside the vascular system, and is activated by platelets, exposed endothelium, chemicals, or collagen slower than the extrinsic pathway, but more important- involves factors XII, XI, IX, VIII.
∙ Explain the role of surface antigens on erythrocytes in determining blood groups
-surface antigens used to distinguish self from foreign matter -unique to individual
-agglutinogens
∙ List the type of antigen and the type of antibodies present in each ABO and Rh blood type
A: A antigens-anti B antibodies
B: B antigens-anti A antibodies
AB: A and B antigens-no antibodies
O: neither antigen-A and B antibodies
Rh: (+) contain Rh antigen and (-) no Rh antigen and anti Rh antibody
∙ Explain the differences between the development of anti-Rh antibodies and the development of anti-A and anti-B antibodies
-anti A/B antibodies appear after birth and are found in plasma -anti-Rh antibodies ONLY form in Rh- individuals who have been exposed to Rh+ blood
∙ Predict which blood types are compatible, and explain what happens when the incorrect ABO or Rh blood type is transfused
-AB is compatible with both A and B
-both A and B compatible with O, but NOT each other
-if the incorrect blood type is transfused, this leads to agglutination of the erythrocytes which are subject to eventual hemolysis
∙ Explain why blood type O- is the universal donor and type AB+ is the universal recipient
-O- is the universal donor because it contains no antigens, but contains anti-A, anti-B, and anti-Rh antibodies
-AB+ is the universal recipient because it contains no antibodies, but contains A, B, and Rh antigens
Heart
∙ Describe the position of the heart in the thoracic cavity -located in the mediastinum, between the lungs
∙ Describe the basic surface anatomy of the chambers of the heart
-right and left ventricles located as the base of the heart
-right/left atriums located superior to the ventricles on either side of the interventricular septum
∙ Explain how the heart functions as a double pump and why this is significant
-pumps blood through both the pulmonary and systemic circuits -this accounts for providing blood to the heart itself as well as the entire body
∙ Describe the layers of the pericardium
-pericardium- double-walled sac surrounding the heart
-epicardium (visceral pericardium)- serous membrane covering the heart
-endocardium-inner lining of the heart and blood vessels
-myocardium-muscular layer (contains fibrous skeleton)
∙ Describe the location and functions of the right coronary arteries and their branches, the cardiac veins, and the coronary sinus
-right coronary artery supplies the R atrium
-right marginal branch supplies lateral side of R atrium and ventricle -posterior interventricular branch provides posterior walls of both ventricles
-anterior portion of the heart holds cardiac vein
-posterior heartmiddle cardiac vein
-left portion of heartleft marginal vein
-all these veins drain into coronary sinus which drains into R atrium
∙ Describe the structure and function of the major arteries and veins entering and leaving the heart
∙ Describe the structure and function of the chambers, septa, atrioventricular valves, semilunar valves, papillary muscles, and chordae tendinae of the heart
-right/left atria: receive blood returning to heart (superior) -r/l ventricles: pump blood into arteries (inferior)
-interatrial septum-separates atria
-interventricular septum-separates ventricles
-atrioventricular valves-controls flow between atria and ventricles -right AV valve is tricuspid
-left AV valve is bicuspid or mitral
-semilunar valves-control flow into great arteries
-pulm. Semilunar: opening between right ventricle
and
pulm. Trunk
-aortic semilunar: opening between left ventricle
and aorta
-chordae tendinae-chords that connect papillary muscles on floor of ventricles
∙ Trace the pathway of blood through the heart, and describe the major factors that ensure one-way flow
1. Blood in systematic capillaries delivers oxygen to body cells
2. Systematic veins return deox. Blood to the right atrium 3. Blood passes from RA through tricuspid valve to RV 4. RV pumps blood through pulm. Valve to pulm. Trunk 5. Pulm. Trunk delivers blood to pulm. Capillaries of left and right lungs-blood becomes oxygenated
6. Pulm. Veins return ox. Blood to LA
7. Blood passes from LA through mitral valve to LV
8. LV pumps blood through aortic valve to aorta
9. Aorta delivers blood to systematic capillaries (cycle starts back at 1)
∙ Differentiate between a cardiac pacemaker and contractile cell.
-pacemaker-rhythmically and spontaneously generate action potentials that trigger contractile cells
-contractile-transmit the electrical signal from the course (pacemaker cells) to the rest of the heart tissue
∙ Describe the histology of cardiac muscle tissue, and differentiate it from that of skeletal muscle.
-striated, short, thick, branched cells
-intercalated discs (three features NOT found in skeletal muscle) 1. Interdigitating folds-folds interlock with each other and increase SA of contact
2. Mechanical junctions-tightly join cardiocytes
Fascia adherens
Desmosomes
3. Electrical junctions (gap)-allows ions to flow between cells-stimulate neighbors
∙ Describe the phases of the cardiac muscle action potential, including ion movements that occur in each phase, and explain the importance of plateau phase.
1. Rapid depolarization phase: voltage-gated Na+ channels activate and Na+ enter-rapidly depolarizing the membrane
2. Initial repolarization phase: Na+ channels are inactivated and some K+ channels open- K+ leak out-small initial repolarization 3. Plateau phase: Ca2+ channels open and Ca2+ enter as K+ exit depolarization prolonged (lengthens the cardiac action potential from 1-5 msec to 200-200 msec which slows HR and allows heart to fill with blood and increases contraction strength)
4. Repolarization phase: Na+ and Ca2+ channels close and K+ continue to exit-repolarization
∙ Contrast the way action potentials are generated in cardiac pacemaker cells, cardiac contractile cells, and skeletal muscle cells.
-contractile cell action potentials include a large, noticeable refractory period
-skeletal muscle fiber action potentials only include a spike at 0 seconds
-pacemaker cell action potentials only include a small climax at 400 msec where full depolarization has been reached
∙ Describe the parts of the cardiac conduction system, and explain how the system functions.
-coordinates the contractions of the heart
-this allows heart to contract independently
-composed of rhythmic electrical signals
1. SA node (initiates each HB and determines HR)
2. signals spread through atria
3. AV node (gateway to ventricles)
4. AV bundle (bundle of His)
5. purkinje fibers (nerve-like processes)
∙ Identify the waveforms in a normal electrocardiogram, and relate the ECG waveforms to atrial and ventricular depolarization and repolarization and to the activity of the conduction system.
-P wave: SA node fires-atrial depolarization and they contract P-R interval: duration of atrial depolarization and AV node delay -QRS complex: ventricular depolarization (masking atrial repolarization)
R-R interval: entire duration of a cardiac action potential Q-T interval: entire duration of a ventricular action potential -ST segment: ventricular systole-plateau in myocardial action potential
-T wave: ventricular repolarization and relaxation
∙ Describe the phases of the cardiac cycle
-systole: atrial of ventricular contraction
-diastole: atrial or ventricular relaxation
∙ Relate the opening and closing of specific heart valves in each phase of the cardiac cycle to pressure changes in the heart chambers
-pressure in ventricles (diastole) lower than atria, pulm. Trunk, and aortaSL valves closed (atrial systole), AV valves open (ventricular filling phase)
-high pressure closes AV valves (ventricular systole)(atrial diastole) (isovolumetric contraction phase) –SL still closed
-pressure in ventricles higher (systole) than pulm. Trunk and aorta SL valves open (atrial diastole) and blood flows into aorta (ventricular ejection) –AV still closed
-(ventricular diastole) pressure in ventricles declines SL valves close (isovolumetric relaxation phase) –AV still closed
∙ Relate the heart sounds to the events of the cardiac cycle.
-S1 occurs when high pressure closes AV valves-isovolumetric contraction phase
-S2 occurs when decreased pressure in ventricles closes SL valves isovolumetric relaxation phase
∙ Relate the ECG waveforms to the normal mechanical events of the cardiac cycle
-PQR portion occurs during the ventricular filling phase -RS portion occurs during the isovolumetric contraction phase -the portion leading up the the T wave, including the T wave, occurs during the ventricular ejection phase
-isovolumetric phase includes a plateau portion of the ECG
∙ Compare and contrast pressure and volume changes of the left and right ventricles and the aorta during one cardiac cycle.
-pressure in the right ventricle reaches it’s max (~30 mm Hg) during the ventricular ejection phase
pressure gradually inc. during the isovolumetric contraction phase
-pressure in the LV reaches its maximum (~120 mm Hg) during the same phase
the pressure rapidly increases during the isovolumetric contraction phase
-pressure in the aorta is extremely high to begin with but follows the climb by the LV during the ventricular ejection phase