Question

Identify the best explanation why and how protein is broken down in the body?

From nutrition class

Answer 1

ANSWER.

Reason for protein breakdown in the body.

    * Proteins are macromolecules and known as the building blocks of the body.

    * It have long chain of aminoacids which are considered as basic units of protein.

    * There are twenty aminoacids in the body and they classified into two groups.

    * In this twenty aminoacids 9 aminoacids are known as essential aminoacids

      and 11 aminoacids are known as non essential aminoacids.

    * Body can not make essential aminoacids (histine,leucine,isoleucine,lysine

      methionine,phenylalanine,,threonine,tryptophan and valine) so it need to be

      came from our diet.

   * Inadequate level of essential aminoacids result in negative nitrogen balance in

     the body.

   * It leads to poor growth and development in both children and adult.

   * 11 non essential aminoacids are also necessary to maintain normal functioning

      of the body and it is synthesized from carbon skeletons and amino groups from

      other aminoacids.

Process breakdown of protein.

            * Digestion of protein begin from stomach due to the absence of protein digesting

               enzymes in the stomach.

             * Pepsin is a enzyme produced by gastric gland in the form of pepsinogen and the

               hydrochloric acid produced by parietal cells of stomach convert pepsinogen into

               pepsin.

            * Pepsin breakdown protein into small units called peptones and proteose.

            * Rennin or chymosin secreted in the stomach also responsible digestion of protein

              into peptides.

            * But all the peptide linkages of protein are not broken in the gastric digestion.it is broken

              by pancreatic (chymotrypsins,trypsins,carboxy peptide) and intestinal juices during digestion

              taken place in the intestine.

            * After protein breakdown into aminoacids in the small intestine it carries to the tissues and liver.

            * Small percentage absobed by stomach and colon then the absorbed aminoacid reach into the

               tissues for metabolism.