Tracheal system

Question 1

Spiracles

Answer 1

• valve like openings on abdomen
• CO2 enters and leaves
• trachea attaches here

Question 2

Trachea

Answer 2

• internal tubes
• strengthened w/ chitin rings
• tracheole branch off, extend throughout tissue and deliver oxygen

Question 3

Diffusion

Answer 3

internal
- respiring cells use up O2, produce CO2 and create a conc. gradient from tracheoles to the atm

Question 4

Mass transport

Answer 4

insect contracts and relaxes abdominal muscles to move gases

Question 5

Anaerobic respiration

Answer 5

• when in flight muscles respire anaerobically producing lactate
• lowers ψ of the cells, water moves from tracheoles to cells via osmosis
• decreases tracheole volume which draws air from atm in

Question 6

adaptation T

Answer 6

tracheoles increase SA

Question 7

Adaptation DD

Answer 7

tracheole walls are thin and short distance between spiracles and tracheoles - short diffusion distance

Question 8

adaptation SG

Answer 8

Use of O2 and production of CO2 sets up steep diffusion gradient

Question 9

Limiting water loss

Answer 9

• low SA:V ratio where water can evaporate
• waterproof exoskeleton
• spiracles can open and close to reduce water loss