CARDIOVASCULAR SYSTEM

Question 1

which side of the heart is bigger

Answer 1

left as it pumps blood all around the body

Question 2

vena cava

Answer 2

bring deoxygenated blood back to the right atrium

Question 3

pulmonary vein

Answer 3

brings oxygenated blood from the lungs back to the left atria

Question 4

pulmonary artery

Answer 4

only artery to carry deoxygenated blood from right ventricle to the lungs

Question 5

what is the tricuspid valve

Answer 5

between right atria and right ventricle

Question 6

what is the bicuspid valve

Answer 6

between left atrium and left ventricle

Question 7

describe the cardiac cycle

Answer 7

deoxygenated blood from veins, vena cava flows into right atrium
open atrioventricular valves allow blood to pass through to ventricles
systole occurs, right atrium contracts, blood flows into right ventricle
the right ventricle contracts soon after, forcing blood along the pulmonary artery towards the lungs
deoxygenated blood flows through pulmonary artery where gas exchange occurs
oxygenated blood from the pulmonary vein fills the left atrium during diastole
systole begins again, left atrium empties its contents into the left ventricle
during systole, the left ventricle contracts, forcing the left atrioventricular valve to close, oxygenated blood is pumped into the aorta

Question 8

what are semilunar valves

Answer 8

between right and left ventricle
between pulmonary artery and aorta

Question 9

what is systole

Answer 9

contraction phase of the cardiac cycle

Question 10

diastole

Answer 10

relaxation phase of the cardiac cycle

Question 11

what is the sinoatrial node

Answer 11

group of specialised cells located in the wall of the heart which send electrical impulses to the cardiac muscle, causing it to contract

Question 12

what does myogenic mean`

Answer 12

capacity of the heart to generate its own impulses

Question 13

describe the cardiac conduction system

Answer 13

1. myogenic, beat starts in the heart itself with an electrical signal in the sinoatrial node
2. impulse spreads through the heart as a wave of excitation
3. SAN electrical impulse spreads through the walls of the atria, causes them to contract and blood is forced into the ventricles
4. impulse passes through the atrioventricular node
   AVN delays transmission of the cardiac impulse (0.1s)
   allows atria to fully contract before ventricular systole begins
   electrical impulse passes down specialised fibers which form the bundle of his which is located in the septum
   bundle of his branches out into 2 bundle branches, before moving to smaller bundles called the purkinje fibers which help ventricles to contract

Question 14

FACTORS AFFECTING THE CHANGE IN
RATE OF THE CONDUCTION SYSTEM