By the ligand receptors on the surface of the cell membrane. How do transport proteins make it easier for certain molecules to diffuse across a membrane.
the binding of a signaling molecule, or ligand, to its receiving molecule, or receptor.
Answer:
The second line of defence is nonspecific resistance, which kills intruders in a broad manner without focusing on specific individuals: phagocytic cells ingest and kill any germs that enter body tissues.
Explanation:
The correct answer is A. Petroleum is not a raw material for the production of biofuels. From the name itself, biofuels are obtained from biomass. Biomass are organic materials for example are the choices given in B, C and D.
Well oxygen has 6 electrons in its outer shell and mg has 2. Oxygen need two to complete it's outer shell and mg needs to lose 2 to gain a complete out we shell.