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Major Elements in Biological Molecules: Proteins

By: HWC, Views: 7151

Proteins are chains of amino acids linked by peptide bonds. The 20 different amino acids used to make all proteins differ only in their side chains, and the properties of these side chains account for the great diversity of protein structure and function. Collagen is an example of how a prote...

Proteins

By: HWC, Views: 6786

Living things must accomplish a great number of tasks just to get through a day, and these tasks are accomplished by a diverse range of biological molecules. In the range of tasks that molecules accomplish, however, proteins reign supreme. Almost every chemical reaction that takes place in living...

Protein catabolism - deamination

By: HWC, Views: 7892

• Digestion hydrolyzes proteins into amino acids, which are transported to the bloodstream. • Amino acids and proteins are not stored. • Instead, they are: • Oxidized to generate ATP. • Used to synthesize new proteins. • Converted to carbohydrates or lipids for storage (if e...

Miller's reaction chamber experiment Animation

By: HWC, Views: 1320

A simple diagram of Stanley Miller and Harold Urey's experimental apparatus. The lower portion of the apparatus was filled with water. The upper portion was filled with a mixture of gases that simulated the earth's early atmosphere. Examples are methane, ammonia, hydrogen and carbon dioxide. ...

Structure of Amino Acid, Peptide Bonds & Polypeptides

By: HWC, Views: 7214

Here are the molecular formulas of three different amino acids. All amino acids share this backbone. The main difference between every amino acid is the side groups seen here, and these side groups give each of the amino acids their different characteristics. But before we get into that, let's ...

Peptide Bond Formation Animation

By: HWC, Views: 1555

During protein synthesis, peptide bonds link amino acids together in the order specified by DNA instructions. In this case, the first two amino acids in the protein are methionine and alanine. Here are ball-and-stick models of these amino acids. Peptide bond formation is a type of condensatio...

Proteins Defined, Hierarchy & Composition of Cells

By: HWC, Views: 7209

Proteins are long chains of amino acids linked together by peptide bonds. Together with the other three biological macromolecules—carbohydrates, lipids, and nucleic acids—proteins are the building blocks of cells. Proteins are the most complex and abundant biological macromolecules in cel...

Membrane Protein and Facilitated Transport (Passive Vs Active)

By: HWC, Views: 7360

Membrane proteins are common proteins that are part of, or interact with, biological membranes. Membrane proteins fall into several broad categories depending on their location. Integral membrane proteins span the membrane, with hydrophobic amino acids interacting with the lipid bilayer and hy...

Secondary and tertiary levels of protein structure Animation

By: HWC, Views: 1649

Amino acid sequence dictates a protein's final shape. The presence of certain amino acids favors a pattern of hydrogen bonding that causes part of the polypeptide chain to coil and twist into an alpha helix. The presence of other amino acids enables hydrogen bonding between strand like re...