Write the path of O2 from trachea to respiring tissue cell. [2 MARKS]
Complete path: 2 Marks Trachea → Bronchus → Bronchioles → Alveoli → Diffusion → Blood → Respiring tissue
Opening to the trachea is covered by a small flap of tissue termed as the ______.
Respiration in insects is called direct because
(a) the cells exchange O2/CO2 directly with the air in the tubes
(b) the tissues exchange O2/CO2 directly with the air in the tubes
(c) the tissues exchange O2/CO2 directly with the air outside through body surface
(d) tracheal tubes exchange O2/CO2 directly with the haemocoel which then exchange with tissues
Define meristematic tissue. Why do meristematic cells lack vacuoles? [2 MARKS]
Write any two differences between breathing and respiration? [2 MARKS]