Photosynthesis is one of the main processes that is basically responsible for the function of all living things. Without it carbon would not be cycled, oxygen would not be made and plants would not be able to creat food for themselves and would have to rely on another source.
Endocrine signaling is hormone based signaling that travels through the blood stream. Many of the sensors and integrating sensors of the endocrine system are located in the brain. The brain barrier contributes to endocrine signalling, such that the brain barrier does not factor in with endocrine signalling. The answer is A
A control group is important to a controlled experiment because it is used in an experiment to establish its validity.
To contract and churn the food to break it down into smaller molecules
