Gas Exchange In Insects

Question 1

Describe how gas is moved through insects.

Answer 1

1. Air enters through open spiracles and diffuses through tubes called trachea
2. Trachea branches into smaller tubes called trachea lies which are directly connected to respiring cells
3. Oxygen diffuses down a concentration gradient to the respiring muscle cells and carbon dioxide diffuses out
4. Insects use rhythmic abdominal movements to maybe air in and out of the spiracles

Question 2

Describe water loss is reduced in insects.

Answer 2

1. Insects have a tough waterproof exoskeleton all over their body
2. Insects have hair around their spiracles which reduce evaporation
3. Insects are able to close their spiracles to prevent water loss

Question 3

Describe structural adaptations of gas exchange surface in insects.

Answer 3

1. Trachea branch into many smaller tracheoles which increases surface area for faster diffusion of oxygen
2. Tracheole walls are thin which creates a short diffusion pathway for faster diffusion of oxygen
3. Cells of insects use up oxygen in respiration which maintains a concentration gradient for the diffusion of oxygen into the muscle cells from the atmosphere
4. Abdominal pumping squeezes tracheoles which increases pressure inside the tracheoles
5. Fluid in the end of tracheoles move out into tissues by osmosis during exercise which increases the diffusion of oxygen through air and also increases surface area of tracheole over which diffusion can take place