Heart anatomy

Question 1

2 circulatory systems

Answer 1

systemic - around body

pulmonary - to lungs and back

Question 2

2 forms of the heart

Answer 2

systolic - contracted

diastolic - relaxed

Question 3

3 layers of the heart

Answer 3

Epicardium, myocardium + endocardium

Question 4

features of epicardium

Answer 4

serous (moisture exuding) layer that protects heart

lubricates pericardial cavity between 2 pericardial layers with pericardial fluid

Question 5

myocardium

Answer 5

muscular layer of heart, thickness varies around heart - thicker around left ventricle

Question 6

endocardium

Answer 6

epithelial layer surrounding the heart. consistent with blood vessels

Question 7

function of circulatory system

Answer 7

• distribution of gases + nutrients
• Chemical signalling
• Thermoregulation
• Inflammation + immure response

Question 8

3 component systems

Answer 8

• heart
• venous
• arterial

Question 9

2 circulatory systems

Answer 9

• pulmonary

- systemic

Question 10

4 valves in order from vena cava to aorta

Answer 10

tricuspid, pulmonary, mitral, aortic

Question 11

3 layers to blood vessels + 2 elastic fibre layers

Answer 11

• tunica intima
• internal elastic fibre
• tunica media
• external elastic fibre
• tunica adventitia

Question 12

Features of tunica intima

Answer 12

endothelium (type of epithelium) consistent with endocardium of the heart

• basal lamina
• thin layer of connective tissue

Question 13

Features of tunica media

Answer 13

elastic fibres and smooth muscle layer

Question 14

Features of tunica adventitia

Answer 14

connective tissue

Question 15

Features of arteries

Answer 15

Thicker tunica media - cope with pressure

• located deep in body
• elastic walls expand under pressure, constrict when not to keep blood flow continuous
• elastic fibres replace smooth muscle layers
• vasa vasorum

Question 16

sympathetic tone

Answer 16

standard lumen size adopted due to tonic (continuous) sympathetic innervation

Question 17

increased/decreased sympathetic tone

Answer 17

increased- vasoconstriction

decreased- vasodilation

Question 18

define Anastomosis

Answer 18

when 2 arteries come together without going through capillary network

Question 19

features of anastomosis

Answer 19

• alternative route for blood flow (collateral)

- severed anastomosis bleed from both directions

Question 20

Features of End artery

Answer 20

-only artery to supply a particular region
- occlusion (blockage) leads to infarction
(irreversible death by hypoxia)

Question 21

4 parts of the aorta

Answer 21

• ascending aorta
• arch of aorta
• thoracic aorta
• abdominal aorta

Question 22

define bifurcation + trifurcation

Answer 22

artery splits into 2 - 3

Question 23

branches of ascending aorta

Answer 23

right/left coronary arteries

Question 24

branches of arch of aorta

Answer 24

• brachiocephalic trunk
• left common carotid artery
• left subclavian artery

Question 25

thoracic aorta to abdominal aorta

Answer 25

become abdominal when it passes the diaphgram

Question 26

contents of neurovascular bundles

Answer 26

arteries, veins + neurones

Question 27

Features of veins

Answer 27

- thin walls, collapse when empty | - valves to prevent backflow of blood

Question 28

3 mechanisms of venous circulation back to heart

Answer 28

- venous valves - skeletal muscle pumps - accompanying veins

Question 29

venous valves

Answer 29

- valves prevent backflow of blood, ensures unidirectional flow

Question 30

skeletal muscular pumps

Answer 30

- muscles contract squeezing blood towards heart

Question 31

accompanying veins

Answer 31

- veins surround arteries and use the pulsation of arteries to push blood through

Question 32

2 types of veins

Answer 32

- superficial and deep

Question 33

2 venous systems

Answer 33

- hepatic portal | - systemic

Question 34

Features of lymphatic circulation

Answer 34

- drains tissue fluid (becomes lymph) - drains to nodes - wbc conduct surveillance - returned to systemic system at root of the neck

Question 35

generation of a heart beat

Answer 35

sa node av node bundle of his purkinji fibres

Question 36

hearts ability to beat uninnervated

Answer 36

autorhythmicity

Question 37

elastic recoil

Answer 37

- elastic fibres recoiling during diastole to keep B.P relatively constant

Question 38

vasa vasorum

Answer 38

- blood supply to tunica media and adventitia as they don't receive nutrients from lumen of artery

Question 39

features of arterioles

Answer 39

- reduce in size | - tunica media has only 1/2 layers of smooth muscle left

Question 40

features of capillaries

Answer 40

- endothelial cells + basal lamina

Question 41

3 types of capillary

Answer 41

- continuous - fenestrated - discontinuous

Question 42

continuous capillaries

Answer 42

- endothelial layer continuous around entire lumen of capillary - muscle, nerve, lung + skin

Question 43

fenestrated capillaries

Answer 43

- small pores in endothelium to allow exchange of materials | - glands, kidney + mucosa gut

Question 44

discontinuous capillaries / sinusoidal

Answer 44

- large gaps in endothelium | - liver, spleen + bone marrow

Question 45

arteriole to venule ( intermediate vessels)

Answer 45

arteriole - metarteriole - capillary - post capillary venule/ thoroughfare channels - venule

Question 46

features of large veins

Answer 46

- thick tunica adventitia with longitudinal smooth muscle