Protein Synthesis

DNA: Captain of the Cell DNA controls the cell by making the proteins the cell needs to do its job DNA’s information is stored in sections called genes Genes are sections of DNA that code for proteins DNA is used to make proteins in 2 steps: Transcription and Translation The Central Dogma: how information in DNA moves from being stored to being used

The Central Dogma DNA RNA Protein Transcription Translation

DNA vs. RNA DNA RNA Nucleus Cytoplasm Double Stranded Ribose Deoxyribose Thymine Uracil Guanine Guanine Adenine Adenine Cytosine Cytosine

Transcription Transcription turns DNA into mRNA Uses messenger RNA (mRNA) to carry DNA’s message from the nucleus to the cytoplasm mRNA copies DNA’s instructions and carries the blueprint to ribosomes

Transcription Happens in 3 Steps DNA unzips in the area of 1 gene One of the unzipped strands of DNA is used as a template to make mRNA RNA Polymerase initiates RNA synthesis on the template strand Cytosine—Guanine; Adenine—Uracil Genetic code is written in groups of 3 bases called codons Each codon codes for 1 amino acid mRNA carries the new gene blueprint from the nucleus to a ribosome

RNA Processing Happens between Transcription and Translation mRNA code for a gene is significantly shorter than the DNA code for a gene DNA has long sections of non-coding DNA called introns Introns are removed from the transcribed mRNA, leaving only coding sequences called exons

Transcription 

Translation Translation turns mRNA into a protein mRNA lines up the first 2 codons with a ribosome made of rRNA in the cytoplasm tRNA are interpreters of the mRNA codon sequence They have 3 bases that are complementary to the codons on mRNA called anticodons Every tRNA also carries a specific amino acid A tRNA carrying the amino acid coded for attaches to the first codon. A second tRNA attaches and a peptide bond forms between the first 2 amino acids The first tRNA detaches and the ribosome shifts down the mRNA

Translation Process repeats until the whole mRNA has been translated into amino acids Finished amino acid chain is a protein

The Central Dogma DNA Protein Transcription Translation RNA

Protein Synthesis http://www.youtube.com/watch?v=h5mJbP23Buo