(d)+Making+Proteins

Complete Biology: pages 192-3 ( Section 11.3 ).

**What are proteins?** Large and complex molecules that play several important roles in the human body. They are made up of thousands and thousands of smaller units named amino acids are connected by long chains.

**What are functions of proteins?** Proteins do most of the work in the cells as well as being a necessity for structure, function and regulation of the body's tissues as well as organs. Below is a list of some of protein's functions:
 * Antibody - binds to foreign particles such as bacteria to protect the immune system
 * Enzyme - takes part in most chemical reactions in cells and help form new molecules
 * Structural component - proteins that provide structure and support for cells
 * builds and repair body tissues
 * source of Energy
 * helps keep skin and nail healthy
 * essential for water balancing and nutrient transportation and muscle contraction

**From DNA --> Protein** Step 1: Each gene carries a series of coded instructions ('code words') for the synthesis of proteins. Step 2: Each code word on the 'DNA' is made up of a three basses(three 'letters') in the same sequence Step 3: Each triplet correspond to a single amino cell within a protein Definitions:

**Triplet:** A triplet is a group of three codes, each corresponding to a third of an amino acid. **DNA:** Self-replicating material found in every cell's nucleus. **mRNA:** Short for messenger RNA. It allows code to pass from the nucleus to the ribosomes in the cytoplasm.

Each DNA triplet code corresponds to three bases that, together, call on an amino acid. There are four bases and twenty amino acids that can be arranged into sixty-four different triplet codes. Three of these act as stop signals that end the protein chain, the remaining sixty-one are linked to an amino acid. mRNA is transcribed using DNA using the base pair A-U, unlike DNA replication which uses the base pair A-T. The message on the DNA is copied onto the mRNA which leaves the nucleus though the nuclear pore and goes to a ribosome. Here, the message on the mRNA is read and an amino acid is built.



The diagram above shows and explains the process of transcription, where DNA is used to make mRNA and the process of translation, where mRNA is used to mae protein. This process only takes about 10 seconds.

media type="youtube" key="983lhh20rGY?rel=0" height="360" width="480" The video above summarises translation and transcription using computer technology and graphics.

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"What Are Proteins and What Do They Do? - Genetics Home Reference." //Genetics Home Reference - Your Guide to Understanding Genetic Conditions//. Web. 08 Feb. 2012. [].