Structure and Function of Heart

Question 1

Atria

Answer 1

blood collects when it enters

Question 2

Ventricle

Answer 2

Pump blood out of heart to lungs or around body

Question 3

Tricuspid valve

Answer 3

Right atrium and right ventricle opens due to pressure - left side of paper

atrioventricular valve

Question 4

Bicuspid valve

Answer 4

Between right atrium and ventricle - opens build up of pressure - right side of paper

atrioventricular valve

Question 5

Semilunar valve

Answer 5

Stop backflow into heart - at aorta and where pulmonary artery leaves to lungs

Question 6

main vein and artery

Answer 6

Vein - vena cava

artery - aorta

Question 7

Cardiac Output

Answer 7

Volume of blood pumped out ech ventricle per minute

CO = SV x HR
CO - ml per minute
SV - ml or l
HR - bpm

Question 8

Stroke volume

Answer 8

volume of blood pumped out each ventricle each time heart beats

Question 9

Heart rate

Answer 9

beats per minute

Question 10

If HR increases

Answer 10

CO increases

Question 11

If SV increases

Answer 11

CO increases

Question 12

Contraction of heart

Answer 12

Systole

Question 12

Relax of heart

Answer 12

Diastole

Question 13

Cardiac cycle

Answer 13

1. Atrial and ventricular diastole (chambers fill with blood)
2. Atrial systole (atria contact and remaining blood pushed into ventricles)
3. Ventricular systole (ventricles contract and push blood out through aorta and pulmonary artery)

Question 14

Heart beat starts in heart itself due to what?

Answer 14

Sino-atrial node (SAN)

Question 15

SAN

Answer 15

found in top right of atrium ans sets rate at which heart contracts.

Electrical impulses carried through muscular walls of both atria - atrial systole

then passed to another node within heart - atrioventricular node which is at lower part of right atrium

once impulse form san reaches avn the impulse is passed to conducting fibres which travel down central wall of heart

impulse then splits up left and right ventricles causing simultaneous contraction (ventricular systole)

Question 16

what causes changes in heart rate?

Answer 16

hormones and nervous system

Question 17

What regulates rate of atrial node through antagonistic actions of ANS (autonomic nervous system)

Answer 17

Medulla

Question 18

autonomic nervous system comprises of 2 antagonist sets of nerves…

Answer 18

1. sympathetic nerve pathway releases noradrenaline which increases HR
2. parasympathetic pathway releases acetylcholine which decreases HR

Question 19

Sympathetic nerve pathways

Answer 19

releases noradrenaline which increases HR

Question 20

Parasympathetic Pathway

Answer 20

Releases acetylcholine which decreases HR

Question 21

Blood pressure is increased and decreased when

Answer 21

Increased during ventricular systole

decreases during diastole

Question 22

Blood pressure measured using what?

Answer 22

Sphygmomanometer

Question 23

2 values measured by sphygamomanometer

Answer 23

systolic value - heart squeezing (intermittent to continuous)

diastolic value. - heart relaxing (continuous flow)

Question 24

blood pressure reading

Answer 24

systolic over diastolic

Question 25

High pressure is known as

Answer 25

hypertension - major risk of cardiovascular disease

Question 26

Average blood pressure

Answer 26

120/80mmHg