What is a protein in red blood cells that binds with oxygen and carries it around the body?

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?

In which part of the body is a ball-and-socket joint found?

What problem would a person most likely have if her kidney did not work correctly?