Answer:
Proteins are like carbohydrates and fats (lipids) because they contain carbon, hydrogen and oxygen. On the other hand, proteins also contain _nitrogen__________ while carbohydrates and fats do not.
Explanation:
Proteins are formed by units: amino acids. These are organic molecules that contain carboxyl (COOH) and amino (NH2) groups. These groups bind to the carbon called alpha (α), which also binds to a side chain (R chain) and a hydrogen atom (H). There are 20 types of amino acids.
A scenario where a cell may be needed to perform a form of endocytosis is when transporting large molecules. A scenario where a cell may be needed to perform a form of exocytosis is when releasing the large molecule from the cell.
Answer:
Smooth and cardiac
Explanation:
Smooth and cardiac muscles are both involuntary.
This means we do not consciously control them. Smooth muscles are found, for example, in the esophagus, and small intestine. The cardiac muscles are found in the heart.
The skeletal muscles are those that we control consciously, such as the muscles for moving our arms and legs.