Respiration in insects is called direct because
A. The tissues exchange O2/ CO2 directly with the air in the tubes.
B. The tissues exchange O2/ CO2 directly with coelomic fluid.
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.
Answer:D
Respiration in insects is called direct because
A. The tissues exchange O2/ CO2 directly with the air in the tubes. B. The tissues exchange O2/ CO2 directly with coelomic fluid. 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.