Cardiovascular System Keywords

Question 1

Myogenic

Answer 1

The capacity of the heart to generate its own impulses

Question 2

Sinoatrial node (SAN or SA node)

Answer 2

A small mass of cardiac muscle found in the wall of the right atrium that generates the heartbeat.
More commonly called the pacemaker

Question 3

Atrioventricular node (AVN or AV node)

Answer 3

Relays the impulse between the upper and lower sections of the heart

Question 4

Systole

Answer 4

When the heart contracts

Question 5

Bundle of His

Answer 5

A collection of heart muscle cells that transmit electrical impulses from the AVN via the bundle branches to the ventricles

Question 6

Purkinje fibres

Answer 6

Muscle fibres that conduct impulses in the walls of the ventricles

Question 7

Sympathetic system

Answer 7

Part of the autonomous nervous system that speeds up heart rate

Question 8

Parasympathetic system

Answer 8

Part of the autonomic nervous system that decreases heart

Question 9

Medulla oblongata

Answer 9

Most important part of the brain as it regulates processes that keep us alive such as breathing and heart rate

Question 10

Chemoreceptors

Answer 10

Tiny structures in the carotid arteries and aortic arch that detect changes in blood acidity caused by an increase or decrease in the concentration of carbon dioxide

Question 11

Baroreceptors

Answer 11

Special sensors in tissues in the aortic arch, carotid sinus, heart and pulmonary vessels that respond to changes in blood pressure to either increase or decrease heart rate

Question 12

Proprioceptors

Answer 12

Sensory nerve endings in the muscles, tendons and joints that detect changes in muscle movement

Question 13

Adrenaline

Answer 13

A stress hormone that is released by the sympathetic nerves and cardiac nerve during exercise which causes an increase in heart rate

Question 14

Stroke volume

Answer 14

The volume of blood pumped out by the heart ventricles in each contraction

Question 15

Ejection fraction

Answer 15

The percentage of blood pumped out by the left ventricle per beat

Question 16

Diastole phase

Answer 16

When the heart relaxes to fill with blood

Question 17

Cardiac output

Answer 17

The volume of blood pumped out by the heart ventricles per minute

Question 18

Cardiac hypertrophy

Answer 18

The thickening of the muscular wall of the heart so it becomes bugger and stronger; also can mean a larger ventricular cavity

Question 19

Bradycardia

Answer 19

A decrease in resting heart rate to below 60 beats per minute

Question 20

Atherosclerosis

Answer 20

Occurs when arteries harden and narrow as they become clogged up by fatty deposits

Question 21

Atheroma

Answer 21

A fatty deposit found in the inner lining of an artery

Question 22

Angina

Answer 22

Chest pain that occurs when the blood supply through the coronary arteries to the muscles of the heart is restricted

Question 23

Stroke

Answer 23

Occurs when blood supply to brain is cut off

Question 24

Steady state

Answer 24

Where the athlete is able to meet oxygen demand with the oxygen supply

Question 25

Blood pressure

Answer 25

The force exerted by the blood against the blood vessel wall

Question 26

Systolic pressure

Answer 26

The pressure in the arteries when the ventricles are contracting

Question 27

Diastolic pressure

Answer 27

The pressure in the arteries when the ventricles are relaxing

Question 28

Venous return

Answer 28

The return of blood to the right side of the heart via the vena cava

Question 29

Plasma

Answer 29

The fluid part of the blood (mainly water) that surrounds blood cells and transports them

Question 30

Haemoglobin

Answer 30

An iron-containing pigment found in red blood cells, which combines with oxygen to form oxyhaemoglobin

Question 31

Myoglobin

Answer 31

Often called ‘muscle haemoglobin’ An iron containing muscle pigment in slow-twitch muscle fibres which has a higher affinity for oxygen than haemoglobin. It stores the oxygen in the muscle fibres which can be used quickly when exercise begins

Question 32

Mitochondria

Answer 32

‘Powerhouse of cell’ | Where respiration and energy production occur

Question 33

Bohr shift

Answer 33

When an increase in blood CO2 and a decrease in pH results in a reduction of the affinity of haemoglobin for oxygen

Question 34

pH

Answer 34

A measure of acidity The range goes from 1-14 Anything less than 7 indicates acidity

Question 35

Vascular shunt mechanism

Answer 35

Redistribution of cardiac output

Question 36

Vasodilation

Answer 36

Widening of blood vessels to increase the flow of blood into capillaries

Question 37

Vasoconstriction

Answer 37

The narrowing of the blood vessels to reduce blood flow into capillaries

Question 38

Arterio-venous difference

Answer 38

A-VO2 diff The difference between the oxygen content of the arterial blood arriving at the muscles and the venous blood leaving the muscles