SAFOLO — 2g — Gas Exchange

Question 1

Describe the graph

Answer 1

What is it showing?

E.g. as the intensity increases, so does the breathing rate

Question 2

Explain the graph

Answer 2

Why is this happening?

E.g. Breathing rate increases because the muscle cells of the body respire more during physical activity to provide more energy needed by muscles

Question 3

Compare the data

Answer 3

Differences and similarities

E.g. In both the unfit and fit, their breathing rate increases to the maximum, levels off and then decreases until it reaches the resting rate

Question 4

Function of the cartilage in the trachea?

Answer 4

Gives the trachea flexibility and keeps the trachea open

Question 5

Air flow order

Answer 5

1. When we breathe in, the air enters our nose and mouth.
2. The air passes over our larynx
3. The air flows down our trachea
4. The trachea splits into the bronchi (left and right) which lead to the left and right lungs.
5. The bronchi split into small air passages known as the bronchioles.
6. The air ends up in the air sacs called alveoli.
7. The gases in the air diffuse into the capillaries to be moved around the body.

Question 6

How does the air going into the lung differ from air moving out?

Answer 6

In the lungs, the amount of oxygen decreases because it is being absorbed into the blood . The amount of carbon dioxide increases because it is coming out of the blood and into the lungs. The amount of nitrogen also decreases in the lungs

Less O2
Same N2 (a bit less)
More CO2
Water vapour (exhaled)

Question 7

Ventilation inhalation

Answer 7

• External intercostal muscles contract, rib cage up and out
• Internal intercostal muscles relax and pulled back to elongated state
• Diaphragm contracts and flattens, pushing abdomen walls outwards
• Volume of thorax increases, pressure of thorax decreases
• Decreased pressure causes air to be drawn into lungs (inhalation)

Question 8

Ventilation exhalation

Answer 8

• External intercostal muscles relax and are pulled back to their elongated state
• Internal intercostal muscles contract, pulling rib cage down and in
• Diaphragm relaxes and forms dome shape
• Thorax decreases in volume, thorax pressure increases
• Increased pressure causes air to be forced out of lungs (exhalation)

Question 9

3 main chemicals in smoke

Answer 9

Nicotine, Tar, Carbon monoxide

Question 10

Nicotine

Answer 10

Addictive drug. Increases blood pressure and heart rate. Narrows arteries (vessels that carry blood). Harden arterial walls which leads to heart attack

Question 11

Tar

Answer 11

Dark, sticky substance. Carcinogen. Damages cilia (hairs that protect lungs from dirt and infection). makes lungs go black. Makes goblet cells produce more mucus, increasing risk of bronchitis

Question 12

Carbon monoxide

Answer 12

Gas which binds with haemoglobin reducing red blood cells’ oxygen carrying capacity. Displaces oxygen in the blood. Deprives the heart, brain and vital organs.

Question 13

Bronchitis

Answer 13

Infection of bronchi. Tar destroys cilia cells so mucus, dirt and bacteria stay in the lungs. Bacteria trapped in mucus causes infections. Leads to smokers cough because of the extra mucus in throat.

Question 14

Emphysema

Answer 14

Air sacs of lungs are damaged and enlarged — breathlessness. Smoke damages alveolar walls and form irregular spaces. Very inefficient gas exchange.

Question 15

Lung cancer

Answer 15

Begins in lungs. Tumours in lungs cause no pain, can’t be removed if too late.

Question 16

CHD (Coronary Heart/Artery Disease)

Answer 16

Arteries damaged and get blocked. Smoking creates plaques (fatty deposit). Narrow arteries. Not working part of heart will get cramped — heart attack.

Question 17

Thorax?

Answer 17

Part of body between Neck and abdomen

Question 18

Ribs?

Answer 18

Bone structure that protects internal organs including lungs

Question 19

Intercostal muscles?

Answer 19

Muscles between the ribs that move ribcage during inhalation and exhalation

Question 20

Diaphragm?

Answer 20

Sheet of muscle at bottom of thorax that changes volume during inhalation and exhalation

Question 21

Trachea?

Answer 21

Windpipe that connects the mouth ad nose to lungs

Question 22

Bronchi?

Answer 22

Thick tubes that divide into two bronchi inside lungs - one bronchus for each lung

Question 23

Bronchioles?

Answer 23

Bronchi will split to form thinner tubes called bronchioles that are connected to alveoli

Question 24

Alveoli?

Answer 24

Tiny air sacs where gas exchange occurs

Question 25

Pleural membrane?

Answer 25

Thin, moist membrane lining the outside of Lungs for lubrication to reduce friction, and to stick outside of lungs to chest cavity for lung to follow chest movement

Question 26

How are alveoli adapted for gas exchange?

Answer 26

• Folded alveoli
• Thin cell walls
• Dense capillary network

Question 27

How does a folded alveoli help gas exchange?

Answer 27

• Folded to increase SA:V ratio for diffusion of gases, increases rate of gas exchange

Question 28

How do thin cell walls of alveoli help gas exchange?

Answer 28

Thin cell walls (one cell thick) to minimise distance of diffusion of gases, therefore increasing the rate of gas exchange

Question 29

How do dense capillary networks in alveoli help gas exchange?

Answer 29

Alveoli surrounded by dense capillary network to provide rich blood supply and creates a strong concentration gradient for the diffusion of gases, therefore increasing the rate of gas exchange

Question 30

Effects of smoking on alveoli?

Answer 30

Tar in cigarettes break down Alveoli walls and causes them to merge together, decreasing the SA:V ratio for gas exchange
Insufficient gas exchange will increase risk of Emphysema

Question 31

Effects of smoking on circulatory system?

Answer 31

• Nicotine narrows blood vessels, straining circulatory system and increases blood pressure
• Narrow blood vessels causes build up of fat globules, increasing risk of CHD
• Carbon monoxide will bind irreversibly to Haemoglobin, reducing capacity of oxygen transport by red blood cells and increases risk of Emphysema