Respiratory System

Question 1

Tidal volume

Answer 1

The volume of air inspired or expired per breath

Question 2

Minute ventilation

Answer 2

Volume of air inspired or expired per minute

Question 3

Inspiratory reserve volume

Answer 3

Volume of air that can be forcibly inspired after maximal breath

Question 4

Expiratory reserve volume

Answer 4

Volume of air that can be forcibly expired after maximal breath

Question 5

Residual volume

Answer 5

Volume of air remaining in lungs after maximal expiration.

Question 6

Gas exchange

Answer 6

Movement of oxygen from air to blood and carbon dioxide from blood to air.

Question 7

Gas exchange at alveoli

Answer 7

Pp of oxygen in alveoli is 100mmhg and in blood vessel is 40 mmhg.

Pp of carbon dioxide in blood vessel is 46mmhg and in alveoli is 40 mmhg.

Question 8

Gas exchange in muscles

Answer 8

Pp of oxygen in blood is 100mmhg and 5mmhg in the muscle.

Pp of carbon dioxide in muscle is 46mmhg and 40mmhg in blood.

Question 9

Respiratory centre

Answer 9

Inspiratory centre - responsible for inspiration and expiration

It send out nerve impulses down phrenic nerve to the inspiratory musvles to contract and passive expiration occurs.

Exploratory cnetre- stimulates the expiratory muscles during exercise

Question 10

Neural control

Answer 10

Repiratory centre responds to changes in blood chemistry whixh increases. Detected by chemoreceptors send impulses to inspiratory centre to increase breathing until blood acidity is normal. The inspiratory centre sends impulses down phrenic nerve to stimulate inspiratory musvles increasing breathing rate.

Question 11

Smoking

Answer 11

Carbon monoxide from cogarettes combined with haemoglobin more readily than oxygen. This reduces the oxygen carrying capacity of blodd increasing breathlessness.

• irritation of trachea and bronchi
• breathlessness
• build up of excess mucus in lungs leading to smokers cough
• increasing risk of COPD