The building blocks of a protein is an amino acid. The body uses the protein to rebuild, repair and maintain tissues. You can find protein in meat, egg whites, tofu, and dairy products.
Hemoglobin is a transport protein. Hemoglobin is considered a transport protein because it carries oxygen through the body. Hemoglobin is part of the circulatory system.
Amylase is an enzyme. Amylase is part of the digestive system. Amylase is part of the digestive system because it helps break down starch and glycogen into simple sugars and can be found in saliva.
A collagen is a structural protein. Collagen gives tissues its structure to stay in a young like state for a period of time and and is part of the integumentary system.
Insulin is a signaling protein. Insulin is used to call for glut 4 transporters which allow glucose into the cell and is part of the endocrine system.