Assessment 3, Part 3

Question 1

where does platelet production occur?

Answer 1

in the red bone marrow

Question 2

what is THPO

Answer 2

thrombopoietin: protein that stimulates that growth and division of cells

Question 3

what is hemostasis?

Answer 3

stoppage of bleeding

Question 4

what are the 3 stages of hemostasis?

Answer 4

1. vascular spasm
2. plug formation
3. blood clotting cascade/coagulation

Question 5

What is the vascular Spasm stage of hemostasis?

Answer 5

a reflex initiated by local pain receptors leading to vasoconstriction of damaged blood vessels, reducing blood loss

Question 6

what is the platelet plug formation stage of hemostasis?

Answer 6

platelets aggregate and adhere to each other and secrete PDGF ADP, and Thromboxane A2.
PDGF is platelet-derived growth factor, ADP is adenosine diphosphate and Thromboxane A2. ADP causes platelets to become sticky. Thromboxane A2 is an eicosanoid.

Question 7

what is the coagulation stage of hemostasis?

Answer 7

the process of blood clotting that requires so many blood clotting factors that activate one another

Question 8

what are most blood clotting factors secreted by?

Answer 8

LIVER

Question 9

which blood clotting factors are not activated by the liver? what are they secreted by instead?

Answer 9

factor 3 “thoromboplastin”= perivascular tissue

factor 8 “fibren-stabilizing-factor”= platelets

Question 10

what is hemophilia?

Answer 10

failure of blood to form clots

Question 11

what is hemophilia A?

Answer 11

lack of blood clotting factor #8

Question 12

what is hemophilia B?

Answer 12

lack of blood clotting factor #9

Question 13

what is hemophilia C?

Answer 13

lack of factor #11

Question 14

what is the epicardium of the heart?

Answer 14

the visceral pericardium; the layer of the serosa membrane that covers the heart

Question 15

what is the myocardium of the heart?

Answer 15

the cardiac muscle cells “cardiocytes”

Question 16

what is the endocardium?

Answer 16

simple squamous epithelial tissue “endothelium”

Question 17

what is the visceral pericardium?

Answer 17

the inner layer of the serosa membrance

Question 18

what is the parietal pericardium?

Answer 18

the outer layer of serosa membrane lining the pericardial cavity

Question 19

what is the paricardial cavity?

Answer 19

the space between the visceral and parietal pericardiums that is filled with serous fluid

Question 20

what is rheumatic heart disease?

Answer 20

antibodies against bacteria attack cells of the heart valves

Question 21

What is the sino artrial node?

Answer 21

a collection of specialized cardiocytes that spontaneously fire every 0.8 seconds

Question 22

How does the cardiac conduction system work?/how does the signal spread through the heart?

Answer 22

Sino Artial Node - Atrioventricular Node - Atrioventricular Bundle - Bundle Branches - Purkinjee Fibers

Question 23

What do the Purkinjee fibers do?

Answer 23

distribute excitation through ventricular myocardium

Question 24

what happens during ventricular filling?

Answer 24

once the AN valves open, 70ml of blood flows from atria to the ventricles to be added to 60ml of remaining blood from the former cycle

Question 25

what is the end diastolic volume?

Answer 25

the volume during relaxation=130ml

Question 26

what happens during volumetric ejection?

Answer 26

AV valve remains closed, semilunar valves open, bentricles contract and 70ml from each ventricle is ejected from each

Question 27

what is the end systolic volume?

Answer 27

the remaining 60ml of blood in the ventricles after ventricular ejection=60ml

Question 28

what happens during isovolumetric contraction?

Answer 28

AV valves close but semilunar valves are not open yet (130ml remains in the ventricles)

Question 29

what happens during isovolumetric relaxation?

Answer 29

semilunar valves close but AV valves are not open yet

Question 30

what is the most significant difference between the action potential of a cardiac muscle cell and a skeletal muscle cell?

Answer 30

cardiac muscle cells have a longer refractory time so they cannot be subject to tetany, whereas skeletal muscle cells are subject to tetany

Question 31

what is a refractory period?

Answer 31

a period during which no stimulus of any strength may initiate a new action potential

Question 32

what is the full name of NAD?

Answer 32

nicotinamide adenine dinucleotide

Question 33

what is the average heart rate?

Answer 33

75 beats/min

Question 34

what is the average stroke volume

Answer 34

70 ml/beat

Question 35

what is the average cardiac output?

Answer 35

heart rate x stroke volume=5.25 L/min

Question 36

what does a blood pressure of 120/80 mean?

Answer 36

the systolic pressure is 120 mmHg (the maximal pressure at the artery resulting from ventricular contraction) and the diastolic pressure is 80 (the minimal pressure measured during ventricular relaxation)

Question 37

what are the 4 examples of hormonal regulation of blood pressure? what are their sources?

Answer 37

1. epinephrine --> adrenal medulla 2. ADH/AVP --> magnocellular neurons in hypothalamux 3. aldosterone --> zona glomerulosa of adrenal cortex 4. ANP and BNP--> atrial cells

Question 38

how does epinephrine regulate blood pressure?

Answer 38

alpha and beta adrenergic receptors in the smooth muscle cells around the coronary arteries contract so that more blood can be pumped to the heart to increase the blood pressure

Question 39

how does ADH regulate blood pressure?

Answer 39

binding to V1R and V2R causes water retention which increases blood volume which increases blood pressure

Question 40

how does aldosterone regulate blood pressure?

Answer 40

aldosterone is a mineral corticoid so it retains sodium and water which increase the blood volume, increasing blood pressure by default

Question 41

how do ANP and BNP regulate blood pressure?

Answer 41

**antagonistic to aldosterone. excrete sodium and water which decreases blood volume and blood pressure

Question 42

what do kidneys release in response to lower than normal blood pressure?

Answer 42

renin! enzyme that breaks down angiotensin I

Question 43

what do the cube-like cells of the alveolus do?

Answer 43

secrete surfactant= keeps alveolus from collapsing

Question 44

what do macrophages in the alveolus do?

Answer 44

dust cells; phagocytosis of debris in lungs