Please answer any that you can asap

Acell in the human nervous system whose primary function is to form myelin and the blood-brain barrier, respond to injury, remove debris, and enhance learning and memory is called a(n) cell.

Tropical rain forests support more species per unit area than any other terrestrial ecosystem. what is one way rain forests are important to the health of the biosphere?

Which of these internal feedback reactions does not need your brain? oa. your leg jumping when it is hit by a reflex hammer b. your deeper breathing when you need more oxygen c. your body temperature rising when you have an infection d. your heart beating faster when you are in danger