Which of the following are functions of protein molecules in an animal?

1. Protein molecules help cells carry out many of their functions, and they are part of body structures such as hair and nails.

2. Protein molecules help cells carry out many of their functions, but they are not part of body structures such as hair and nails.

3. Protein molecules do not help cells carry out many of their functions, and they are not part of body structures such as hair and nails.

4. Protein molecules are part of body structures such as hair and nails, but they do not help cells carry out many of their functions.

Proteins are one of the four major biomolecules in living systems. Proteins play a major role in the physiological, structural and metabolical processes in living organisms. They help cells carry out many functions when they acts as enzymes and hormones. Enzymes and hormones are proteinous chemical substances that catalyzes and speedens up physiological reactions respectively.

In addition, proteins are major structural components in animals. For example, keratin is a protein that makes up the hair and nails of animals. They provide structural support in parts of the body they are found.