Hunger can be defined as a physiological drive to find and eat food a sensation caused by distension of the stomach and small intestine starvation a psychological drive to eat

The correct answer is "a physiological drive to find and eat food." "Physiological" refers to the everyday functions that living organisms perform. Hunger falls under the category of physiological, because it is a feeling that makes an organism want to eat (which is a normal, everyday function). An "appetite" (not hunger), is psychological, which means an organism eats because it's surrounded by good food, or because it's sad, for example.

Proteins are the workhorses of the cell, controlling virtually every reaction within as well as providing structure and serving as signals to other cells. proteins are long chains of  amino acids  , and the exact sequence of the amino acids determines the final structure and function of the protein. instructions for that sequence are encoded in  genes  . to make a particular protein, a messenger ribonucleic acid (mrna) copy is made from the gene (in the process called  transcription  ), and the mrna is transported to the  ribosome  . protein synthesis, also called  translation  , begins when the two ribosomal subunits link onto the mrna. this step, called initiation, is followed by elongation, in which successive amino acids are added to the growing chain, brought in by transfer rnas (trnas). in this step, the ribosome reads the  nucleotides  of mrna three by three, in units called  codons  , and matches each to three nucleotides on the trna, called the anticodon. finally, during termination, the ribosome unbinds from the mrna, and the  amino acid  chain goes on to be processed and folded to make the final, functional protein