1.2: Cardiovascular and respiratory systems

Question 1

Pulmonary circuit

Answer 1

circulation of blood through the pulmonary artery to the lungs and pulmonary vein back to the heart

Question 2

Systemic circuit

Answer 2

circulation of blood through the aorta to the body and vena cava back to the heart

Question 3

Oxygenated blood

Answer 3

blood saturated with oxygen and nutrients, such as glucose

Question 4

Deoxygenated blood

Answer 4

blood depleted of oxygen, saturated with carbon dioxide and waste products

Question 5

Conduction system

Answer 5

a set of structures in the cardiac muscle which create and transmit an electrical impulse, forcing the atria and ventricles to contract

Question 6

Myogenic

Answer 6

the capacity of the heart to generate its own electrical impulse, which causes the cardiac muscle to contract

Question 7

Diastole

Answer 7

the relaxation phase of cardiac muscle where chambers fill with blood

Question 8

Systole

Answer 8

the contraction phase of cardiac muscle where the blood is forcibly ejected into the aorta and pulmonary artery

Question 9

Heart rate

Answer 9

the number of times the heart beats per minute (resting HR, approximately 72 bpm)

Question 10

Stroke volume

Answer 10

the volume of blood ejected from the left ventricle per beat (resting SV, approximately 70 ml)

Question 11

Cardiac output (Q)

Answer 11

the volume of blood ejected from the left ventricle per minute. HR x SV = Q (resting Q, approximately 5 l/min)

Question 12

Bradycardia

Answer 12

a resting heart rate below 60 bpm

Question 13

Venous return

Answer 13

the return of blood through the right atria through the veins

Question 14

Sub-maximal

Answer 14

a low-to-moderate intensity of exercise within a performer’s aerobic capacity

Question 15

Maximal

Answer 15

a high intensity of exercise above a performer’s aerobic capacity that will induce fatigue

Question 16

Frank-Starling mechanism (Starling’s law)

Answer 16

increased venous return leads to an increased stroke volume, due to an increased stretch of the ventricle walls and therefore force of contraction

Question 17

Cardiac Control Centre (CCC)

Answer 17

a control centre in the medulla oblongata responsible for HR regulation

Question 18

Sympathetic nervous system

Answer 18

part of the autonomic nervous system responsible for increasing HR, specifically during exercise

Question 19

Parasympathetic nervous system

Answer 19

part of the autonomic nervous system responsible for decreasing HR, specifically during recovery

Question 20

Vasodilate

Answer 20

widening of arteries, arterioles and pre-capillary sphincters

Question 21

Vasoconstrict

Answer 21

narrowing of arteries, arterioles and capillary sphincters

Question 22

Inspiration

Answer 22

drawing of air into the lungs

Question 23

Expiration

Answer 23

expelling of air from the lungs

Question 24

Blood pooling

Answer 24

accumulation of blood in the veins due to gravitational pull and lack of venous return

Question 25

Active recovery

Answer 25

low-intensity activity post exercise to maintain elevated heart and breathing rates

Question 26

Vascular shunt mechanism

Answer 26

the redistribution of cardiac output around the body from rest to exercise which increases the percentage of blood flow to the skeletal muscles

Question 27

Arterioles

Answer 27

blood vessels carrying oxygenated blood from the arteries to the capillary beds, which can vasodilate and vasoconstrict to regulate blood flow

Question 28

Pre-capillary sphincters

Answer 28

rings of smooth muscle at the junction between arterioles and capillaries which can dilate or constrict to control blood flow through the capillary bed

Question 29

Vasomotor control centre

Answer 29

the control centre in the medulla oblongata responsible for cardiac output distribution

Question 30

Vasomotor tone

Answer 30

the partial state of smooth muscle constriction in the arterial walls

Question 31

Alveoli

Answer 31

clusters of tiny air sacs covered in a dense network of capillaries which together serve as the external site for gaseous exchange

Question 32

Gaseous exchange

Answer 32

the movement of oxygen from the alveoli into the blood stream and carbon dioxide from the blood stream into the alveoli

Question 33

Haemoglobin

Answer 33

an iron-rich globular protein in red blood cells which can chemically combine with four O2 molecules to form oxyhaemoglobin

Question 34

Oxygen

Answer 34

the essential gas required for aerobic energy production in the muscle cells

Question 35

Carbon dioxide

Answer 35

the waste product of aerobic energy production in the muscle cells

Question 36

Breathing rate

Answer 36

the number of inspirations or expirations (breaths) per minute (resting, approximately 12-15 breaths/min)

Question 37

Tidal volume

Answer 37

the volume of air inspired or expired per breath (resting, approximately 500ml)

Question 38

Minute ventilation

Answer 38

the volume of air inspired or expired per minute. TV x f = VE (resting, approximately 6-7.5 l/min)

Question 39

Respiratory control centre (RCC)

Answer 39

a control centre in the medulla oblongata responsible for respiratory regulation

Question 40

Inspiratory centre (IC)

Answer 40

a control centre within the RCC responsible for inspiration

Question 41

Expiratory centre (EC)

Answer 41

a control centre within the RCC responsible for expiration

Question 42

Partial pressure

Answer 42

the pressure exerted by an individual gas held in a mixture of gases

Question 43

Diffusion

Answer 43

the movement of gases across a membrane down a gradient from an area of high pressure (or concentration) to an area of low pressure (or concentration)

Question 44

Diffusion gradient

Answer 44

the difference in areas of pressure (or concentration) from one side of a membrane to the other

Question 45

Association

Answer 45

the combining of oxygen with haemoglobin to form oxyhaemoglobin

Question 46

Dissociation

Answer 46

the release of oxygen from haemoglobin for gaseous exchange

Question 47

Oxyhaemoglobin dissociation curve

Answer 47

a graph showing the relationship between pO2 and percentage saturation of haemoglobin

Question 48

Bohr shift

Answer 48

a move in the oxyhaemoglobin dissociation curve to the right caused by increased acidity in the blood stream