Your answer is c: hydrogen bonds
Answer:
D
Explanation:
All of the other examples are positive
Answer:
plasma membrane/ cell membrane
Acetylcholine (ACh)
Acetylcholine is an organic chemical that functions in the brain and body of many types of animals as a neurotransmitter.
Facilitated diffusion of substances crossing the cell (plasma) membrane takes place with the help of proteins such as channel proteins and carrier proteins.