Female mosquitoes feed on the blood of mammals. In an investigation, mosquitoes were released into a chamber with a source of carbon dioxide at one end. Most of the mosquitoes moved towards the carbon dioxide source.
Identify the type of response shown, and use the information to justify your answer.
[2]
Suggest the advantage of this response to the mosquito.
[1]
A second, identical chamber with no carbon dioxide source was set up as a control. Explain why this control was needed.
[2]