Gas Exhange In Insects

Question 1

Where are the spiracles located

Answer 1

Along the thorax and abdomen

Question 2

Function of the spiracles

Answer 2

Air enters and leaves the system through the spiracles, water is also lost.
Minimise water loss
To open/close when o2 demanded is higher/lower often due to exercise (which makes them open)

Question 3

Properties/ structure of the tracheae

Answer 3

Largest tube in the insect respiratory system (1mm diameter)
Lined with spirals of chitin which keep them open if the are pressed
Divide into tracheoles (0.6-0.8 micro meters)

Question 4

Function of the tracheae

Answer 4

Serves as a passage for air

Question 5

Properties/ structure of the tracheloes

Answer 5

Vast number give a large surface area for gaseous exchange
0.6-0.8 micro meters in diameter
Towards the end of the teacheloes there is the trachole fluid which limits penetration of air for diffusion

Question 6

How does ventilation occur

Answer 6

Pumping of abdomen and thorax
Increase volume = decrease pressure
Air rushes into the spiracles down a pressure gradient

Question 7

what ways to insects have of dealing with high o2 demand

Answer 7

Mechanical ventilation, additional pumping of abdomen

Collapsable

Question 8

Tracheal fluid

Answer 8

Found towards the end of the tracheloes
This limits penetration of air for diffusion
When o2 demand builds up the fluid moves out of the tracheloes by osmosis, exposing more SA for gas exchange
Keeps moisture which is good for diffusion