What type of protein helps inolecules move through a cell membrane?
A. Channel protein
B. Carrier protein
C. Receptor protein
D. Glycoprotein

Carrier protein help molecules to move through a cell membrane.

Explanation:

Carrier protein help molecules to move through a cell membrane.

Carrier proteins transport ions and molecules either through facilitated diffusion or by secondary active transport. These proteins also bind to a specific molecule that needs to be transported.

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation:

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.