Insects

Question 1

How does insect blood flow

Answer 1

Hemolymph ( green/yellow)
Freely through the body cavity making direct contact with organs and tissues

Question 2

What is special about the insect circulation system

Answer 2

Doesn’t carry oxygen so blood doesn’t contain red blood cells

Question 3

How do insects reduce water loss

Answer 3

• rigid outer skeleton (impermeable to gases) covered with a waterproof cuticle
• relatively small surface area
• network of internal tubes (tracheae) to bring oxygen to the cells

Question 4

What is the spiracle

Answer 4

A small hole in insect thorax or abdomen for air to enter and leave
Water evaporates when spiracle is open
Most of the time it’s shut

Question 5

How does oxygen move through the insect

Answer 5

Oxygen enters open spiracle which then shuts ( maintaining oxygen concentration gradient). It moves through tracheal system ( tracheae ——>tracheoles

Question 6

How do insects facilitate respiratory system

Answer 6

• diffusion gradient
• ventilation = movement of muscles creates mass movement of air in and out of tracheae (needed when flying) =maximises gas exchange as more air enters quicker maintaining high concentration gradient

Question 7

Limitations of insect respiratory system

Answer 7

• relies on diffusion
• must have a short diffusion pathway for effective diffusion= limits size of insect

Question 8

How does structure of insects gas exchange insure a large SA

Answer 8

There are many small branching tracheoles

Question 9

Describe one way transportation of oxygen differs in insects than in fish

Answer 9

Insect - blood not in involved in transporting oxygen

Question 10

Adaption of the insect respiratory system

Answer 10

Water next to muscle so the oxygen diffuses into it and high concentration gradient maintained