Answer:
A control group setup in an experiment is used to see if there are other variables in play during the experiment. Say I was to test which type of blood is a shark's favorite, my control would be putting red paint in one of the set ups to see if the shark is just interested in the red color of blood, instead of the other types of blood.
Explanation:
A. external
These types of signals are observed when there is a cut on the body. The epidermal cells lose contact with one another and divide faster until they are in contact once again. After they come into contact, division slows down again.
Number 5 would be the best awnser.
As a scientist who remains impartial can more accurately conclude his data while doing experiments.
