BIOLOGY

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 * PORTFOLIO NUMBER 2**

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 * This is a real example of a colon cancer. eventhough it looks awful, it is how it looks, and in this video is very easy to identify cancer.

PORTFOLIO NUMBER 1** media type="youtube" key="ttEw7Mb19jo" height="344" width="425" This is a video with a clear example of the most common ART ( assissted reproductive technique) used in infertility treatments. It is short but it showws the procedure very clearly and with a good but simple explanation. Note: There are other videos about the other ARTs, that you can see by entering into the link at the bottom. Steffano Solari

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Reviewed by GL: Partially copied from: [] [] = = = = = = = = = = = = __COFACTORS:__ = = A cofactor is a non-protein chemical compound that is bound to a protein and is necessary for the protein's biological activity. These proteins are commonly enzymes and cofactors can be considered "helper molecules/ions" that assist in biochemical transformations. Cofactors can be divided into two broad groups: organic cofactors, such as flavin or heme, and inorganic cofactors: such as the metal ions Mg2+, Cu+, Mn2+ or iron-sulfur clusters.

__ENZYMES:__

Enzymes are biomolecules that catalyze chemical reactions. Practically all known enzymes are proteins. In enzymatic reactions, the molecules at the beginning of the process are called substrates, and the enzyme converts them into different molecules, called the products. Almost all processes in a biological cell need enzymes to occur at significant rates.

__RIBOZYMES:__ A ribozyme (from ribonucleic acid enzyme, also called RNA enzyme or catalytic RNA) is an RNA molecule that catalyzes a chemical reaction.

Although most ribozymes are quite rare in the cell, their roles are sometimes essential to life. For example, the functional part of the ribosome, the molecular machine that translates RNA into proteins, is fundamentally a ribozyme. Ribozymes often have divalent metal ions such as Mg2+ as cofactors.

EXAMPLES: -HDV ribozyme -Mammalian CPEB3 ribozyme -VS ribozyme

__VITAMINS:__

A vitamin is an organic compound required as a nutrient in tiny amounts by an organism. A compound is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet.