Module 3 - Circulatory System

Question 1

What are the three constituents of blood once spun?

Answer 1

plasma
buffy coat
RBC

Question 2

What are the 5 types of leukocytes + basic function?

Answer 2

Neutrophils: bacterial infection
	Lymphocytes: immune
	Monocytes: macrophages
	Eosinophils: parasitic infections
	Basophils: histamine

Question 3

What are platelets derived from?

Answer 3

fragments of megakaryocytes

Question 4

What 3 things do platelets contain?

Answer 4

albumins (transport steroid + thyroid hormones), globulins (transport iron, lipids, vitamins, antibodies), clotting proteins (fibrinogen + prothrombin = coagulation)

Question 5

What are the four stages of haemostasis?

Answer 5

1. Injury
2. Spasm
3. Platelet plug (soluble)
4. Fibrin clot (insoluble)

Question 6

Where does haematopoiesis occur, what stimulates it?

Answer 6

red bone marrow from haematopoietic stem cells, when there is not enough oxygen in blood there is a release of erythropoietin which stimulates this process

Question 7

Who is the universal donor and who is the universal acceptor?

Answer 7

donor: O-
acceptor: AB+

Question 8

What are the three layers of a vessel wall and what do they contain?

Answer 8

Adventitia: CT prevents over distension
Media: contraction + relaxation of smooth muscle
Intima: smooth endothelial surface + simple squamous for exchange

Question 9

What are the three types of arteries?

Answer 9

Elastic- closer to heart, high pressure
Arterioles: thick wall relative to lumen, reduce BP for capillaries
Muscular: more smooth muscle

Question 10

What do the aorta and pulmonary artery carry?

Answer 10

• aorta (arch, ascending, descending, thoracic, abdominal): oxygenated blood to body via LV
• pulmonary artery: deoxygenated blood from RV to lungs, left/right is pulmonary trunk

Question 11

What is the prominent layer in veins?

Answer 11

adventitia

Question 12

What doe the vena cavae and pulmonary vein carry?

Answer 12

• vena cavae: superior + inferior, deoxygenated blood from body to RA
• pulmonary vein: oxygenated blood from lungs to heart

Question 13

Valves are extensions of which layer?

Answer 13

intima

Question 14

What are the three mechanisms of venous return?

Answer 14

Venous pressure (high in venules, low in vena ava entering heart)
Respiratory pump
Muscle pump (squeezes veins)

Question 15

What are the three types of capillaries?

Answer 15

1. Continuous: tight junctions between cells
2. Fenestrated: many pores
3. Sinusoids/discontinuous: very large fenestrations

Question 16

What are the three layers of the heart wall and what are they made up of?

Answer 16

Endocardium: innermost, endothelium + CT
Myocardium: cardiac muscle, bulk of wall, intercalated discs
Epicardium: outermost, CT covered by mesothelium, visceral layer of serous fluid

Question 17

What are the layers of the pericardium?

Answer 17

Pericardium: forms pericardial sac
Outer fibrous (dense irregular CT), parietal, serous, pericardial cavity, visceral (closest to myocardium)

Question 18

Describe the structure of the cuspid valves.

Answer 18

chordae tendinae are thin and connect valve to wall/papillary muscles

Question 19

When do semilunar valves open and close?

Answer 19

atrium to ventricles, open when ventricular > atrial pressure, close when ventricles contract and blood pushes against underside of cusps

Question 20

What is the heart valve memory tool?

Answer 20

Toilet Paper My Ass

Tricuspid, Pulmonary, Mitral, Aortic

Question 21

What are the pulmonary and systemic circuits?

Answer 21

Pulmonary circuit: RV to lungs to heart

Systemic circuit: heart to body to heart

Question 22

What are the three methods used to aid foetal circulation?

Answer 22

Foreman ovale: opening in heart wall, RA to LA, circumvents lungs
Ductus arteriosus: connects pulmonary artery and descending aorta
Ductus venosus: umbilical vein to foetal vena cava, circumvents liver

Question 23

What is the pacemaker otherwise called and what does it do? And what happens next?

Answer 23

SA node
generates AP

to AV node then Purkinje fibres

Question 24

What is systole?

Answer 24

Systole: contraction, decreased volume, increased pressure, valves open, 0.3 seconds

Question 25

What is diastole?

Answer 25

Diastole: relaxation, increased volume, decreased pressure, chamber fills, 0.5 seconds

Question 26

What do the five stages of the cardiac cycle involve?

Answer 26

1. Atrial systole: atria fill, contract, increase in pressure, and valves open so blood flows to ventricles
2. Early ventricular systole: atria relax (diastole), atrium volume increase so pressure decrease, ventricles start contracting, AV valves close, semilunar valves still closed, NO MOVEMENT OF BLOOD (ISOVOLUMETRIC CONTRACTION)
3. Late ventricular systole: ventricle pressure increases as ventricles hold blood, semilunar open, blood forced out of ventricles to arteries
4. Early ventricular diastole: ventricular muscles contract, blood flows back into valve cusps, semilunar valves shut, BUT ventricular pressure > atrial pressure, AV valves closed, ISOVOLUMETRIC CONTRACTION
5. Late ventricular diastole: all chambers relaxed (diastole), ventricular < atrial pressure, AV valves open, atria rapidly fill with blood, passive flow from veins to atria to ventricles, atria + ventricular filling occurs (70%), next cycle begins, atria contract

Question 27

What are the waves on an electrocardiogram and what do they show?

Answer 27

P wave: atrial depolarization
QRS complex: ventricular depolarization
T wave: ventricular repolarisation

Question 28

What do the systolic and diastolic aspects of BP show?

Answer 28

Systolic (during ventricular systole), diastolic (just prior to opening of AV valve)

Question 29

How is CO measured and what is it regulated by?

Answer 29

CO = SV x HR (L/min) (regulated by oxygen requirements and capacity of vessels)

Question 30

What do the different nodes, muscle and vessels regulate?

Answer 30

Rate of signal: SA node
Conduction velocity: AV node
Contractility/force: cardiac muscle
Relaxation/speed: cardiac muscle
Vasoconstriction/dilation: blood vessels

Question 31

What are other regulators of blood pressure/flow?

Answer 31

(intrinsic/extrinsic (baro (arch/carotid)/chemoreceptors (peripheral aortic/carotid), medulla oblongata (CV centre, chemo/baro received), endocrine (can override NS))

Question 32

What hormones affect BP + BV?

Answer 32

Endocrine: adrenaline (constrict + dilate), ADH (increase BP), angiotensin II (increases BP), atrial natriuretic peptide (decreases BP)

Question 33

What is lymph derived from?

Answer 33

plasma filtrate

Question 34

What is the path of lymph?

Answer 34

Capillaries to interstitial space to lymph vessels to lymph nodes (materials removed before releasing to blood) to lymph vessels to blood

Question 35

What are the organs of the lymphatic system?

Answer 35

bone marrow, thymus (T cell factory), spleen (filters blood, lymphocyte maturation), lymph nodes (filtration, produce lymphocytes)

Question 36

What are three blood disorders?

Answer 36

anemia, leukocytosis, thrombocytosis

Question 37

What is coronary heart disease?

Answer 37

blockage of coronary arteries

Question 38

What is atherosclerosis?

Answer 38

build-up of plaque in arteries

Question 39

What is myocardial infarction and angina?

Answer 39

myocardial infarction (blockage of vessel), angina (temporary blockage)

Question 40

What is cardiomyopathy?

Answer 40

muscle becomes thick and stiff

Question 41

What is cerebrovascular disease? (stroke)

Answer 41

blockage of vessel in brain

Question 42

What is rheumatic heart disease?

Answer 42

inflammation and damage to valves

Question 43

What is congenital heart disease?

Answer 43

problem in structure of heart present at birth