Dissection

This week in biology we have been looking at the different exchange systems in animals. We specifically looked at fish and locusts because there gas exchange system is very different to our own.

Firstly we dissected a locust. I really enjoyed doing this because I love trying to work on small intricate things. As a result I managed to cut open the locust in such a way that it was very easy to see the trachioles and the trachea. I thought that this was truly amazing how different there whole exchange system was. The fact that they don't have any blood and the oxygen that they breath in goes straight to the muscle tissues. Here is a picture of my locust and if you look carefully at the abdomen you can see some thin white lines which are the trachea. 

After this we dissected a fish head to look at the gills . Firstly I was amazed by the flaps of scale like matter that unfolded when the mount opened, I thought that was really cool. Then when it got around to taking the gills out I probably could have done it better with larger utensils, however I managed to remove one gill pretty much from the base. I then looked at it under the microscope which allowed me to see the Gill lamellae and the Gill filaments. Which was interesting to see because I know that for efficient diffusion you need a large surface area, a short diffusion distance and a large concentration gradient. And how fish do this I thought was interesting the counter current flow system and the large surface area due to the filament and lamellae.