University:
Cambridge College
Course:
SCI 225W | Foundations in Biology
Academic year:

2023
Views:

484

Pages:

2
Author:

M Theodore

Proteins Proteins are composed of the elements carbon (C), hydrogen (H), oxygen (N), sometimes the elements phosphorus (P), and sulfur (S). 1. Protein Formation Proteins are formed from amino acids, namely:  Essential amino acids, namely amino acids that cannot be formed by the body. There are 8, namely: isoleucine, leucine, lysine, methionine, valine, tryptophan, threonine, and phenylalanine.  Nonessential amino acids, namely amino acids that can be synthesized by the body. Examples: alanine, asparagine, glycine, glutamine, and proline. 2. Function of Protein In our body, protein has several functions, including:  Enzyme ingredients to catalyze biochemical reactions, for exampletrypsin.  Reserve protein, stored in several materials as food reserves, for example in the aleurone layer (corn kernels), ovalbumin (egg white).  Transport proteins transfer certain substances or elements, for example hemoglobin to bind O2 .  Contractile proteins, for contraction of certain tissues, for example myosinfor muscle contraction.  Protective proteins, protect the body against foreign substances, for example antibodies which resist the entry of foreign molecules (antigens) into the body.  Toxins are poisons that come from animals or plants, for example snake venom.  Hormones are proteins that function as regulators of processes in the body, for example the hormone insulin, in animals the hormone auxin and gibberellin in plants.  Structural proteins are proteins that make up the structure of cells, tissues and bodies of living organisms, for example glycoproteins for cell walls, keratin for hair and feathers. 3. Source of Protein Based on the source, there are 2 types of protein, namely: a. Animal protein Namely protein that comes from animals, for example: meat, fish, eggs, milk and cheese. b. Vegetable protein Namely protein that comes from plants, for example: nuts.Protein deficiency can cause hunger edema (hongeroedem) and kwashiorkor. 4. Protein Metabolism Protein metabolism is catalyzed by several enzymes, namely:       Pepsin, breaks down proteins into amino acids. Renin, converts caseinogen to activated casein (milk).by milk. Chemotrypsin, breaks down proteins into peptides and acids amino. Trypsin, converts proteins into peptides and amino acids. Erepsin turns pepton into amino acid. Peptidase, converts polypeptides into amino acids. Protein is absorbed by the intestinal wall in the form of amino acids, through the portal vein to the liver.In the amino acid metabolism process, the decarboxylation process separates the carboxyl group from the amino acid into a new bond, which is an intermediate substance that still contains nitrogen elements.Next, a transamination process occurs which results in the transfer of an amino acid group (NH2 ) from an amino acid to another bond, becoming an amino acid that is different from the first amino acid.

Lecture Notes: Proteins

Related Documents

Recommended Documents

Details

Description

Related Documents

Struggling with your assignment and deadlines?

Free up your schedule!

Take 5 seconds to unlock