Gas exchange wrong answers

Question 1

(c) Tidal volume is the volume of air inhaled and exhaled during a single
breath when a person is resting. The tidal volume in a person with
emphysema is reduced compared with the tidal volume in a healthy
person.
Suggest and explain how a reduced tidal volume affects the exchange of
carbon dioxide between the blood and the alveoli.

Answer 1

Less carbon dioxide will move out of lungs so there will be reduced diffusion between blood and alveoli so slower movement of carbon dioxide out of blood.

Question 2

Q3.
(a) Describe and explain the mechanism that causes lungs to fill with air.

Answer 2

Diaphragm muscle contracts and external intercoastal muscles contract which causes volume increase and pressure decrease. This leads air to move down a concentration gradient.

Question 3

Q4.
(a) Particulate matter is solid particles and liquid particles suspended in air.
Polluted air contains more particulate matter than clean air.
A high concentration of particulate matter results in the death of some
alveolar epithelium cells. If alveolar epithelium cells die inside the human
body they are replaced by non-specialised, thickened tissue.
Explain why death of alveolar epithelium cells reduces gas exchange in
human lungs.

Answer 3

Reduced surface area so increased distance for diffusion and reduced rate for gas exchange.

Question 4

(e) Use your knowledge of gas exchange in leaves to explain why plants
grown in soil with very little water grow only slowly.

Question 5

Describe the pathway taken by an oxygen molecule from an alveolus to the
blood.

Answer 5

oxygen diffuses from the alveolar air space into blood down its concentration gradient across alveolar epithelium then across capillary endothelium.