> Insect Dissection

Question 1

What insects are best to dissect

Answer 1

• Big insects like grasshoppers, cockroaches, locusts are best bc theyre easier to handle
• They must also be humanely killed fairly recently

Question 2

How to dissect the gaseous exchange system in insects

Answer 2

1. First, fix the insect to a dissecting board. You can put dissecting pins through its legs to hold it in place
2. To examine the tracheae, you’ll need to carefully cut & remove a piece of exoskeleton from along the length of the insect’s abdomen
3. Use a syringe to fill the abdomen w saline solution. You should be able to see a network of very thin, silvery-grey tubes - these are the tracheae. (They look silver bc theyre filled w air)
4. Examine under a light microscope using a wet mount slide. You should be able to see the rings of chitin in the walls of the tracheae - these are there for support (like rings of cartilage in human trachea)