The answer is C. Population size
Answer:
if a molecule is too large it cannot pass. also it depends on the concentration of a specific substance inside the cell. similarly, if a molecule is polar it cannot penetrate the phospholipid bilayer.
there are proteins that work as channels and pumps that allow these molecules to pass
Explanation:
Answer: Substances that are protein based cannot cross the lipid cell membrane, but can exert their effect by binding to the proteins based receptors present on the lipid bilayer.
Explanation:
Hormones such as calcitonin , Parathyroid hormone and pituatry horomones are proteins and water soluble.They cannot cross lipid bilayer but can bind to ligand binding protein receptors.
These receptors are protein macromolecules that are specific in nature for specific hormones.
After binding to the receptors, these hormone-recpetor complexes activate second messengers and regulate the downstream effects.
Answer:Option A
Explanation: The snail breaths in the O2 which will then exhale CO2, therefore the plant will take that and process the CO2 back into O2.