Gas Exchange Lab Report

This report will cover the adaptations relating to gas exchange in insects, fish and mammals. These all have different gas exchange systems but work in similar ways. All the animals studied have the same characteristics in order for them to be able to work properly.
Overview
The gas exchange system is the process in which oxygen enters the cells of many living animals. Some factors that affect how efficient a gas exchange system is are things such as the distance that the molecules have to go before the oxygen enters the cells of the animal. The gas exchange system has to be moist in order for the process of diffusion to take place. When an animal needs to replenish oxygen it has to absorb it across tiny cell membranes deep in their gas
Diffusion occurs when particles of gas flow from one place that has a high concentration of oxygen to an area of low concentration. In this process oxygen gas is exchanged for carbon dioxide. Oxygen is needed by all living species because it is needed to burn fuel in the cells of the body. After the body has finished taking in the oxygen and carried out the diffusion process carbon dioxide is expelled as a gas. Carbon dioxide needs to be expelled because it is a waste product and the body has finished using all of the oxygen. There are several factors that make for an efficient gas exchange system. These include a large surface area for taking in the oxygen, has to have a thin permeable membrane that always remains moist. Also the shorter the diffusion distance the more effective the gas exchange system. The gas diffusion system for three species is discussed
The oxygen is collected by the blood as it passes over the alveoli and the blood is subsequently circulated throughout the body by the heart. After this process occurs carbon dioxide is then expelled through the air sacs and then back out of the lungs. This is the process of gas exchange and allows humans to stay alive.

Comparison

Humans, fish and insects all use similar process for exchanging oxygen into energy and expelling carbon dioxide as a waste product. The common features that they all have is the use of permeable membranes to absorb oxygen and transfer it to the blood to provide energy.
Fish have to retrieve the oxygen from the water whereas insects and humans obtain it from the air. Because fish live in water their gas exchange system has to be more efficient to cope with the lack of oxygen in the water.
Insects, because they are small, have tiny spiracles so that no dirt and debris can enter and cause harm. They can also open and close their spiracles to help protect against impurities being inhaled. The oxygen also enters directly into the cells unlike humans who breathe through their noses.
Humans are like fish and insects in the diffusion process in that they have similar filtering systems for the oxygen prior to it being