The nervous system is responsible for… defending against disease like the flu or common cold.

receiving and processing stimuli from the body.

breaking down food and extracting nutrients.

exchanging gases between the body and the environment.

Amino acids contain the elements carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur. of the 20 amino acids found in humans, 11 are called "nonessential" because they can be manufactured by the body when needed. which elements in these 11 amino acids are commonly obtained from the metabolism of sugar molecules?

Why do some dna fragments move farther than others during gel electrophoresis? a. because their shapes are different b. because they are different types of molecules c. because the samples are different colors d. because their masses are different

This is one of the five kingdoms in the older biological succession. organisms in this kingdom are prokaryotic.