1.2 The Respiratory System

Question 1

Tidal volume

Answer 1

Volume of air breathed in or out per breath

Question 2

Inspiratory reserve volume

Answer 2

Volume of air that can be forcibly inspired after a normal breathe

Question 3

Expiratory reserve volume

Answer 3

Volume of air that can be forcibly expired after a normal breathe

Question 4

Residual volume

Answer 4

The amount of air that remains in the lungs after maximal expiration

Question 5

Minute ventilation

Answer 5

Volume of air breathed in or out per minute. Number of breaths x tidal volume

Question 6

Muscles that contract during inspiration at rest

Answer 6

Diaphragm and external intercostal muscles

Question 7

Muscles that contract during inspiration during exercise

Answer 7

Diaphragm, external intercostal muscles, sternocleidomastoid and pectoralis minor

Question 8

Muscles that contract during expiration at rest

Answer 8

Passive process where diaphragm and external intercostal muscles just relax

Question 9

Muscles that contract during expiration during exercise

Answer 9

Internal intercostal muscles and abdominal muscles

Question 10

How does smoking impact the respiratory system?

Answer 10

increases the risk of CHD due to damage of coronary heart vessels
irritation of the trachea and bronchi
increases risk of lung cancer due to inhalation of harmful substances
restricted oxygen transport due to carbon monoxide attaching to haemoglobin
narrowed airways due to inflammation of walls and lining
Reduces aerobic endurance

Question 11

Partial pressure

Answer 11

The pressure exerted by an individual gas when its exists within a mixture of gases

Question 12

Diffusion

Answer 12

The movement of gas molecules from an area of high concentration an area of low concentration

Question 13

Concentration/diffusion gradient

Answer 13

Often referred to as the concentration gradient. It explains how gases flow from an area of high concentration to an area of low concentration. The steeper this gradient, the faster diffusion occurs

Question 14

Features of alveoli that assist gaseous exchange (3)

Answer 14

Large surface area for a bigger contact area
Moist one cell thick walls allows for a short diffusion pathway
Narrow diameter for a slow passage for blood

Question 15

How does oxygen and carbon dioxide move between alveoli and blood capillaries?

Answer 15

Diffusion occurs where gases move from an area of high concentration to low concentration

Oxygen moves from the aveoli to the blood capillaries as there is a lower partial pressure in the capillaries

Carbon dioxide moves from blood capillaries to the alveoli for the same reason

Question 16

Describe the process of gas exchange which occurs at the muscle

Answer 16

The partial pressure of oxygen has to be lower at the tissues than in the blood for diffusion to occur

This lower partial pressure allows oxygen to diffuse from the blood into the muscle until equilibrium is reached

Question 17

Diffusion pathways of oxygen and carbon dioxide

Answer 17

Oxygen = alveoli -> blood -> muscles

Carbon dioxide = muscles -> blood -> alveoli