Help Identify the boundary separating watersheds?

A. Drainage basin
B. Valley
C. Plateau
D. Divide

Which statement best describes a keystone species? o a. it has littlelmenetic variation. it has an extremely high population. 0 b. 0 c. it remains unaffected by all environmental changes. od. it has a strong influence on the ecosystem. 0 e. it's the first species to populate a new ecosystem.

Explain why phospholipid molecules form a bilayer. (3 marks)

What processes take place before the mature mrna exits the nucleus?