Transcription & Translation Protein Synthesis Transcription & Translation

Protein Synthesis Overview The steps of protein synthesis can be seen in the diagram. Video Link

Protein Synthesis= Transcription & &Translation

Genetic Code DNA's job is to give instructions for making proteins. It does this in the form of the "genetic code" The genetic code is the order of the nitrogen bases; adenine(A), thymine (T), cytosine (C), and guanine (G) within the DNA molecule. RNA is part of the protein making process. It differs from DNA in several ways.

What is RNA? RNA is made of nucleotides like DNA, but there are three important differences between DNA and RNA: 1. RNA has the sugar ribose instead of deoxyribose in DNA 2. RNA is single-stranded instead of double- stranded like DNA 3. RNA contains the base uracil instead of thymine, SO, the base pairing rules for RNA are A-U and C-G Animation

Types of RNA There are three types of RNA 1. messenger RNA (mRNA): copies instructions from DNA in nucleus and carries them to the ribosome 2. ribosomal RNA (rRNA): ribosomes are made of rRNA 3. transfer RNA (tRNA): carries the amino acids to the ribosome, and matches them to the coded message on mRNA

Protein Synthesis, Step 1: Transcription The job of all three types of RNA is to work together to make a protein (protein synthesis) using the instructions from DNA. (see foldable model) Step 1: Transcription, takes place in nucleus DNA unzips and mRNA is made from one strand of the DNA. When finished, the mRNA travels to the ribosome and the DNA zips closed and remains in the nucleus. The mRNA is a messenger that carries the genetic code to the ribosome.

RNA Editing RNA Editing: occurs after transcription Removes introns that are "junk sections" of DNA Splices together the exons, which are the portions of DNA that code for protein remember exons=expressed ANIMATION

Protein Synthesis, Step 2: Translation Step 2: Translation takes place on the ribosome mRNA codons are paired with tRNA anticodons tRNA carries anticodons attached to amino acids. The anticodon on tRNA matches up with the complementary codon on mRNA. The process continues until a stop codon is reached and the protein is complete

Central Dogma of Biology The Central Dogma of Biology states that information is transferred from DNA to RNA to protein. In the nucleus In the nucleus In the cytoplasm

2 Types of Codon Readers