Protein+Synthesis

Protein Synthesis: Overview

 * DNA's Role**
 * DNA stores/transmits information
 * This information directs cell activities
 * Proteins are the products of the DNA message


 * Proteins**
 * Proteins are found in meat, the human body, dairy products, beans, etc.
 * Enzymes are proteins that cause chemical reactions
 * They are large 3-D molecules made of folded and twisted sub-units called "Amino Acids"


 * Amino Acids**
 * Have 3 parts:
 * An Amine Group
 * An Acid Group
 * An "R" Group (20 types)
 * Amino Acid forms a chain of acids called a polypeptide.
 * Arrangement of Amino Acids is based on information from the DNA
 * Then it folds and twists itself into a protein.
 * Shape of protein based on the chemistry of the "R" group
 * Some attract/repel each other depending on if they're polar or nonpolar
 * Some, like sulfides bond covalently forming a "bridge"


 * Protein Production**
 * DNA base sequence is important
 * Sequence is transcribed in nucleus onto an RNA strand
 * RNA is translated into an Amino Acid sequence (polypeptide chain)
 * Polypeptides are edited, folded, and jointed together to make a protein.

**
 * Genetic Code
 * 3 "letters" make 1 amino acid "word"
 * The code is redundant
 * Multiple combinations form one amino acid in order to prevent mistakes

Funny human demo of protein synthesis. media type="youtube" key="u9dhO0iCLww" width="425" height="350"

Transcription
Transcription is the process of making Messenger RNA from a DNA template to carry the code for a specific gene to the ribosome where it is translated into a polypeptide chain.

Promoter (TATA) transcription unit (gene)-Terminator media type="youtube" key="mQClpqDBlSs" width="425" height="350"
 * Helicase unzips DNA.
 * RNA polymerase creates a RNA strand that is complementary to the DNA strand (but instead of Thymine there is Uracil).
 * This single strand is called messenger RNA and it travels to the ribosome where it gets translated.

Translation
media type="youtube" key="NJxobgkPEAo" width="425" height="350"
 * 1) Messenger RNA (M-RNA) formed in transcription carries the coded information __from the DNA to the ribosome__.
 * 2) T-RNA moves to the attachment sight on the ribosome and attaches its anti-codons to the respective codons (group of 3 m-RNA nucleotides) on the M-RNA.
 * 3) These anti-codons code for specific Amino Acids which (as the T-RNA attaches more anti-codons ) bond to form a polypeptide chain.
 * 4) The Polypeptide chain may combine with other polypeptide chains to form specific proteins.