OCR AS Biology 3

Welcome to your OCR AS Biology 3

1. An essential feature of alveoli which contributes towards efficient gas exchange.
2. What is the function of mRNA in protein synthesis?
3. Which does not happen when you inhale?
4. Which of the following contains cartilage?
5. What is the correct sequence of breathing in order starting from inhalation?

a) Air is forced out of the lungs.
b) The diaphragm rises during exhalation.
c) The volume of the lung increases and air pressure in the lung decreases.
d) Air enters the lungs.
e) The volume of lungs decreases and the air pressure in the lungs increases.
6. Which is not a main component of cigarette smoke?
7. Which of the following is a symptom of chronic bronchitis?
8. The substance in tobacco which decreases the oxygen carrying capacity of haemoglobin.
9. Select the incorrect statement regarding smoking.
10. Stomata does not close in which of the following circumstance?
11. Which is not a method used in examining tumours in the lungs?
12. Select the correct statement about nicotine.
13. Which does not happen when you exhale?
14. What is the countercurrent principle in the respiratory system of a fish?
15. Select the incorrect statement about stomata.
16. Select the correct statement about gills.
17. Why do large mammals have difficulties regulating body temperature in hot climates?
18. Select the correct statement regarding water and heat loss in organisms.
19. Which of the following is a lung disease?