Receptor molecules on the surface of cells bind specific molecules called, in general,

Receptor molecules on the surface of cells bind specific molecules called, in general, ligands.

Explanation:

These ligands can be hormones or different signaling molecules.

answer: the answer is b

relative humidity, temperature and dew point -- are bound together in the mathematical relationship below. relative humidity changes when temperatures change. because warm air can hold more water vapor than cool air, relative humidity falls when the temperature rises if no moisture is added to the air. so i would say a