Proteins are large molecules or biological macromolecules consist of one or more long chains of amino acid residues (amino acids are connected to each other by a peptide bond). Proteins are responsible for many physiological functions within all the living organisms, including catalyzing metabolic reactions, replication of DNA, responsible for responding to stimuli and transporting many biological vital molecules from one location to another and also help in transport of molecules across the membranes.
Proteins differ from another protein primarily in their amino acids sequence which is controlled by the nucleotide sequence of the genes and which finally also results in protein folding into a specific three-dimensional structure that determines its activities in physiological systems.
Why is Protein important for us?
Protein is one of the most important and vital biological substance that is found in each and every cell in the human body. The interesting fact is that next to water protein is the most abundant substance in the human body. This protein is manufactured inside human body by utilizing the nutrient which is consumed by a human. It is very essentially used in many biological vital functions for maintenance of normal physiology. We can consider our regular food consumption as the protein intake.
Some of the main reasons proteins should be in our diet
1. Repair and Maintenance
Proteins are called as the building block of cells, tissues and all the biological substances. It is called the building block because protein is responsible for vital maintenance of all kind of tissue growth and reparation, including normal physiological functions. All these things like hair, skin, eyes, muscles of different kind and organs are all made of proteins. This is the main reasons why children need to consume more amount of protein per pound of body weight as compared to the adults. Children need new cell for their growth and development.
2. Act as a source of energy
Protein is one of the major sources of energy. When the consumption of protein is more than what you need for body tissue maintenance and other vital necessary functions, human body use it as a source of energy. On the other hand, if the amount of protein intake is not sufficient then the other sources of energy such as carbohydrates and other can be used.
Protein is structural components for some hormones. These are the biological components that help to control many physiological functions that involve the interaction of several tissue systems. Insulin is a very well known hormone which is a small protein hormone that is responsible for regulating blood sugar level in human body. It is also responsible for the physiological interaction of organs such as the pancreas and the liver. Secretin, which is another protein hormone, is the biological substance which takes part in the digestive process by stimulating different biochemical mechanisms in the pancreas and the intestine for the secretion of necessary digestive juices which is needed for the digestion.
4. Major components of Enzymes
Enzymes are made of protein that helps to increase the rate of biochemical reactions (both catabolic and anabolic) in the body. Without enzymes, most of the vital and essential chemical reactions in the body would not take place efficiently without the help of enzymes. For example, a particular type of enzyme help in reactions of digesting large macromolecules like protein, carbohydrate, and fat molecules into smaller molecules, while some other help to assists the creation of DNA.
5. Transportation and Storage of Molecules
Protein plays a vital role as a transporter in our body. Hemoglobin is a complex protein which is the major component found in RBC and it is responsible for transporting oxygen from lungs to all tissues. Protein also acts as a transporter in the cell membrane and in many other biological membranes. Protein also helps in storing many biological substances. Ferritin is a protein complex that is a combination of protein with iron and it acts as a source of stored iron.
Protein is the major components for the manufacturing of antibodies which are main components of our immune system as it helps our body to fight against viruses, bacteria, fungi and many other harmful microorganisms which affect our body. They often work in conjunction with the other immune system cells. For example, these antibodies identify and then surround antigens in order to keep them contained until they can be destroyed by white blood cells.