Topic 2

Question 1

2.1

Answer 1

Structure and function of the ventilatory system

Question 2

Components of the ventilatory system

Answer 2

Mouth
Nose
Pharynx
Larynx
Trachea
Bronchi
Bronchioles
Lungs
Alveoli

Question 3

Functions of the conducting airways

Answer 3

Low resistance pathway for airflow
Defence against harmful substances or chemicals that can be inhaled
Warms and moistens air

Question 4

Pulmonary ventilation

Answer 4

Pulmonary ventilation is the inflow and outflow of air into the lungs

Question 5

Total lung capacity

Answer 5

The volume of air in the lungs after maximum inhalation

Question 6

Vital capacity

Answer 6

The maximum volume of air that can be exhaled after a maximum inhalation

Question 7

Tidal volume

Answer 7

The volume of air breathed in and out in any one breath

Question 8

Expiratory reserve volume

Answer 8

Volume of air in excess of tidal volume that can be exhaled forcibly

Question 9

Inspiratory reserve volume

Answer 9

The volume of air a person can inhale in excess of their tidal volume

Question 10

Residual volume

Answer 10

Volume of air still contained in the lungs after a maximal exhalation

Question 11

Explain the mechanics of ventilation in the human lungs

Answer 11

The diaphragm contracts and the intercostal muscles allow the ribs to expand allowing the lungs to contain more air.

Boyle’s law states that an increase in pressure leads to a decrease in volume and an increase in volume leads to a decrease in pressure.

Question 12

Describe nervous and chemical control of ventilation during exercise

Answer 12

Ventilation increases as a direct result of increases in blood acidity levels (low pH) due to increased carbon dioxide content in the blood detected by the respiratory centre. This results in an increase in the rate and depth of inhalation.

Neutral control of ventilation includes lung strech receptors, muscle proprioreceptors and chemoreceptors.

The role of hydrogen ions and reference to partial pressure of oxygen are not required.

Question 13

Outline the role of hemoglobin on blood

Answer 13

98.5% of oxygen in the blood is transported by hemoglobin whithin red blood cells

Question 14

Explain the process of gaseous exchange at the alveoli

Answer 14

The delivery of oxygen from the lungs to the bloodstream, and the elimination of carbon dioxide from the bloodstream to the lungs. These processes occur through diffusion.

Question 15

2.2

Answer 15

Structure and function of the cardiovascular system

Question 16

Composition of blood

Answer 16

Composed of:
Plasma (55%)
Red blood cells (45%) - Erythrocytes
White blood cells and platelets (<1%) - Leucocytes

Question 17

Functions of erythrocytes, leucocytes and platelets

Answer 17

Erythrocytes - Contain haemoglobin which is responsible for transporting oxygen

Leucocytes - Protect the body from infection an diseases

Platelets - Assists the process of repair following injury (blood clotting)

Question 18

Anatomy of the heart - Chambers

Answer 18

Right atrium
Left atrium
Right ventricle
Left ventricle

(On diagrams left is right and right is left)

Question 19

Anatomy of the heart - Valves

Answer 19

Going from left to right on diagrams (right to left in real life)

Tricuspid
Pulmonary
Aortic
Bicuspid

Question 20

Anatomy of the heart - Blood vessels

Answer 20

Inferior vena cava
Pulmonary artery
Pulmonary vein
Aorta

Question 21

Pulmonary and systemic circulation

Answer 21

Pulmonary circulation - The flow of deoxygenated blood from the right ventricle, through the pulmonary artery, to the lungs where it becomes oxygenated and then travels through the pulmonary veins back to the heart, ready to be pumped to the rest of the body.

Systemic circulation - The flow of oxygenated blood from the left ventricle, through the aorta to the rest of the body.

Question 22

Intrinsic and extrinsic regulation of heart rate

Answer 22

The heart has its own pacemaker, but heart rate is also influenced by sympathetic and parasympathetic branches of the autonomic nervous system and by adrenaline.

Question 23

The sequence of excitation of the heart muscle

Answer 23

The electrical impulse is generated at the sinoatrial node (SA node) and travels across the atria to the atrioventricular node (AV node) and then to the ventricles, which allows the heart to beat

Question 24

Describe the relationship between heart rate (HR), cardiac output (CO) and stroke volume (SV) at rest and during exercise

Answer 24

Cardiac output = Stroke volume x Heart rate

At rest, CO, SV and HR remain constant
During exercise HR and SV increase, therefore CO is larger

Question 25

Analyse cardiac output, stroke volume and heart rate for different populations at rest and during exercise

Answer 25

Men vs Women
Men have a lower resting HR but they are equal at max
Men have a higher SV compared to women
Men have a higher VO2 max
Women peak is late teens, men peak is early 20s

Young vs Old
Young people have a higher HR than older people
Young people therefore have a higher SV
Dependant on training

Trained vs Untrained
Trained people have a lower resting HR but at max are equal
Trained people have a higher SV
Trained people therefore have a higher VO2 max

Question 26

Explain cardiovasuclar drift

Answer 26

Cardiovascular drift is the increase in heart rate and decrease in stroke volume during exercise. The stroke volume decreases as when a person sweats, their blood viscosity changes and becomes thicker which makes it harder to pump.

Question 27

Systolic and diastolic blood pressure

Answer 27

Systolic blood pressure - the force excerted by blood on arterial walls during ventricular contraction

Diastolic blood pressure - the force excerted by blood on arterial walls during ventricular relaxation

Question 28

Systolic and diastolic blood pressure pressure during static and dynamic exercise

Answer 28

At rest, systolic pressure and diastolic blood pressure remains constant

During static exercise, systolic blood pressure increases and diastolic blood pressure increases

During dynamic exercise, systolic blood pressure increases slowly and diastolic blood pressure remains constant

Question 29

Compare the distribution of blood at rest and the distribution of blood during exercise

Answer 29

At rest, blood is distributed equally throughout the body as all muscles are working more or less the same

During exercise, blood is distributed to the muscles that are doing the most work and therefore need the most oxygen

Question 30

Describe the cardiovascular adaptations resulting from endurance exercise training

Answer 30

As the left ventricular volume increases, the stroke volume also increases and the heart rate decreases.
Capilarisation is increased and arterio-venous oxygen difference is increased.

Question 31

Explain maximal oxygen consumption

Answer 31

Maximal oxygen consumption/VO2 max is the maximum amount of oxygen that a person breathes in whilst exercising at their maximum level.

Question 32

Discuss the variability of maximal oxygen consumption in males vs females, old vs young, trained vs untrained

Answer 32

Older people generally have a higher maximal oxygen consumption compared to younger people, but it is dependant on how active and fit they are

Males tend to have a higher VO2 max compared to females as their stroke volume is on average higher at max.

Trained people have a higher VO2 max compared to untrained people as they have a higher max stroke volume

Question 33

Discuss the variability of maximal oxygen consumption with different types of exercise

Answer 33

Running vs arm ergometry

Running requires a higher maximal oxygen consumption when compared to arm ergometry as it involves a greater muscle mass. This means more oxygen is required to allow the muscles to function. It is also important to consider that previous training in each exercise will change the maximal oxygen consumption required.