circulatory system

Question 1

what do the cardiovascular and lymphatic system do

Answer 1

Transport fluid through body. Distribution of gases and molecules, chemical signaling, thermoregulation, mediate inflammation and defense response.

Question 2

pulmonary and systemic circulation

Answer 2

right atrium – right ventricle – lungs – left atrium – left ventricle – body – back to RA

Question 3

pulmonary circulation

Answer 3

to lungs to be oxygenated

Question 4

systemic circulation

Answer 4

supplies the rest of body with oxygenated blood

Question 5

systole and diastole

Answer 5

systole = contraction. diastole = relaxation

Question 6

walls of heart. 3 layers

Answer 6

epicardium, myocardium, endocardium

Question 7

epicardium

Answer 7

external layer

Question 8

myocardium

Answer 8

middle layer, cardiac muscle, pumps most of blood, very strong

Question 9

endocardium

Answer 9

internal, endothelium of blood vessels connecting w the heart

Question 10

great vessels

Answer 10

superior vena cava. pulmonary trunk, divides into L&R arteries. pulmonary veins x4. inferior vena cava

Question 11

valves

Answer 11

atrioventricular (between atrium and ventricle) there’s a L&R one. left = mitral valve. right = tricuspid valve. Semilunar (blood leaving left and right ventricles), left = aortic. right = pulmonary

Question 12

conduction system in heart

Answer 12

impulse starts at SA node, causing both atria to contract. travels to AV node at AV septum. travels down right and left bundles in interventricular septum. spreads out to myocardium through conducting fibres. both ventricles contract

Question 13

arterial supply and venous drainage components

Answer 13

blood vessels, arteries, artery branches, tone

Question 14

naming branches

Answer 14

Bifurcate (splits into 2) or trifurcate. Terms like ‘common’ or ‘trunk’ indicates the artery will divide

Question 15

arteries

Answer 15

Often part of neurovascular bundle, high pressure, named by anatomical position, round lumen, carry oxygenated blood, typically deeper than veins.

Question 16

tone

Answer 16

smooth muscle in arterioles can contract. vasodilation or vasoconstriction

Question 17

vasodilation

Answer 17

relaxation of muscle, increase blood flow.

Question 18

vasoconstriction

Answer 18

contraction of muscle, reduce blood flow. The muscle contraction can help prevent blood loss during injury.

Question 19

anastomoses

Answer 19

arteries connect together without intervening capillary network. This provides alternative routes for blood flow for the blood if a blockage occurs. alternative routes called collateral circulation

Question 20

end arteries

Answer 20

the only arterial blood supply to given area (no collateral vessels). Untreated occlusion of an end artery results in infarction of territory.

Question 21

infarction

Answer 21

Infarction = irreversible cell death due to lack of oxygen (hypoxia).

Question 22

where does systemic arterial blood enter first

Answer 22

aorta

Question 23

aorta : elastic recoil

Answer 23

Receives blood at high pressure during systole, elastic walls expand under pressure. Elastic recoil maintains peripheral flow during distole, aorta has many branches supplying whole body

Question 24

branches of aorta

Answer 24

1) brachiocephalic trunk 2) left common carotid artery 3) left subclavian artery

Question 25

upper arm blood supply

Answer 25

Comes from left subclavian artery, this then becomes left axillary artery then left brachial artery, close to elbow joint it then bifurcates to give left radial artery and left ulnar artery. Same artery but changes name as it travels down arm.

Question 26

abdomen supply

Answer 26

• Abdominal aorta supplies abdomen. It then bifurcates into 2 common iliac arteries, which splits again into 2 external iliac arteries and 2 internal iliac arteries to supply pelvis/lower limb.

Question 27

venous return

Answer 27

blood flows back to heart with help from: venous valves, in limb veins valves are present to ensure unidirectional flow back to heart against gravity. Skeletal muscle pumps, contraction of muscles in lower limb. Venae comitantes (accompanying veins), small veins run in groups with an artery in a sheath, arterial pulsation pushes venous blood along

Question 28

2 sets of veins

Answer 28

superficial and deep

Question 29

2 main venous systems

Answer 29

Hepatic portal = drains venous blood from GI tract and associated organs to liver for cleaning. systematic = drains blood from all organs to vena cava

Question 30

capillaries

Answer 30

form extensive vascular networks, lined with single layer of endothelium, narrow lumen (one red blood cell at a time), allow for exchange of gases, metabolites and waste products.