- Protein are the building block of the body.
- Collagen is found as strong non-elastic white fibres in tendons, cartilage and bone.
- Elastin is found as yellow elastic fibres in ligaments and joint capsules.
- Keratin is found as a horny impermeable protein in skin, hair, feathers, nails and hooves.
- Lipoproteins of cell membranes, viral coat proteins, fibroin are found as spider silk and cocoon silk, sclerotin found in insect exoskeletons, and mucoproteins found in lubricating joint (synovial) fluid.
- Protein is a major source of energy.
- Insulin, a small protein, is an example of a hormone that regulates blood sugar.
- Secretin, is another example of a protein hormone. This substance assists in the digestive process by stimulating the pancreas and the intestine to create necessary digestive juices.
- Enzymes are proteins that increase the rate of chemical reactions in the body.
- Hemoglobin is a protein that transports oxygen throughout the body.
- Ferritin is an example of a protein that combines with iron for storage in the liver.
- Actin and myosin found in muscles and dynein making up the structure of cilia and flagella.
- Protein forms antibodies that help prevent infection, illness and disease.
- Messenger proteins, such as some types of hormones, transmit signals to coordinate biological processes between different cells, tissues, and organs.
- Proteins are also essential for moving polarized or charged molecules and large molecules across cell membranes.
- When the body’s energy sources are low, it begins to degrade proteins for use as an alternative energy source.
- Blood proteins such as albumin and globulin function to maintain fluid balance in the body.