the structure and function of the heart Flashcards Preview

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Flashcards in the structure and function of the heart Deck (29):
1

the heart has 4 chambers

right atrium
right ventricle
left atrium
left ventricle

2

the right side collects

deoxygenated blood from the body and pumps it to the lungs to collect oxygen

3

The left side collects

oxygenated blood from the lungs and pumps it to the body

4

the walls of the heart are made of

cardiac muscle that can contract continuously without causing fatigue

5

deoxygenated blood returning

from the body via the vena cava and fills the right atrium

6

The build-up of pressure during atrial diastole forces open

open the atrioventricular(AV) valve and blood flows into the right ventricle during ventricular diastole

7

The right atrium contracts, forcing

forcing all the blood into the right ventricle(atrial systole)

8

once full, the right ventricles muscular walls contract(ventricular systole),

closing the AV valve and force the blood up through the semi-lunar valve and out through the pulmonary artery to the lungs.

9

oxygenated blood returning from the lungs via the

pulmonary vein filla the left atrium(during atrial diastole)

10

The build up of pressure during atrial diastole forces open the

atrioventricular valve and blood flows into the left ventricle. The atrium contracts forcing all the blood into the ventricle.

11

once full, the left ventricle muscular walls contract(ventricular systole), closing the

AV valve and forcing the blood up through the semi-lunar valve and out through the aorta to the body organs.

12

The opening and closing of the atrio-ventricular (AV) and semi lunar(SL) valves are responsible

responsible for the heart sounds heard with a stethoscope

13

cardiac output is the volume of blood pumped out by

either ventricle (out of the heart) per minute

14

Stroke volume is the volume of blood pumped out by

either ventricle during one systole.

15

cardiac output is determined by heart rate and stroke volume.

CO=HRxSV

16

The cardiac cycle is the pattern of

contraction (systole) and relaxation (diastole)

17

The heartbeat originates

in the heart itself

18

The sinoatrial node(SAN) also known as the pacemaker is situated

in the wall of the right atrium

19

The SAN ensures both atria contract simultaneously by sending

out electrical impulses that are carried through the muscular walls of atria

20

The sino-atrial node SAN or pacemaker sets the rate at which

cardiac muscle cells contract

21

the timing of cardiac cells contracting is controlled is by the

electrical impulses from the SAN spreading through the atria to the atrioventricular node (AVN) and through the ventricles

22

The electrical impulses generated in the heart produce currents that can be detected by

an electrocardiogram (ECG)

23

The medulla in the brain regulates

the rate of the SAN through the antahonsitic action of the autonomic nervous system(ANS)

24

sympathetic accelerator nerves release nor-acetylcholine which

decreases the heart rate

25

the parasympathetic nerves to the heart release acetylcholine which decreases

the heart rate

26

blood pressure changes in the aorta during the

cardiac cycle

27

measurements of blood pressure is performed using a

sphygmomanometer

28

a typical reading for a young adult is

120/70 mmHg

29

hypertension(high blood pressure) is a major risk

factor for many diseases and conditions , including coronary heart disease