1. RNA and Protein Synthesis
12-3
RNA and Protein Synthesis

2. Genes
Genes are coded DNA instruction that control the production of proteins within the cell
the first step in decoding the message of DNA is copy part of the nucleotide sequence from DNA to RNA

3. Structure of RNA
Almost the same as DNA – they are long chains of nucleotides – sugar, phosphate and nitrogen base
3 main differences
Different sugar
DNA = deoxyrobose, RNA = ribose
DNA is a double helix, RNA is a single strand
RNA has Uracil (U) instead of Thymine (T)

4. Types of RNA
mRNA – (messenger) RNA molecule that carries copies of instructions from a gene to the ribosome
tRNA – (transfer) type of RNA molecule that transfers each amino acid to the ribosome
rRNA – (ribosomal) type of RNA that helps make up ribosomes

5. DNA vs RNA

6. Protein Synthesis Two main steps Transcription Translation
Takes place in the nucleus
Translation
Takes place at the ribosomes

7. Transcription
Transcription is the copying of the information from DNA to mRNA
RNA polymerase is an enzyme that binds to DNA and separates the DNA strands. Then it uses one strand of DNA as a template to make nucleotides of RNA
The enzyme will only bind to a part of the DNA know as a promoter

8. Transcription

9. The Genetic Code
Proteins get made by joining together amino acids into long chains called polypeptides
The language that RNA uses to determine the amino acid sequence is called the genetic code

10. Every 3 nitrogen bases is called a codon or a “word”
Each codon is a code for a different amino acid

12. Translation
Translation is when the cell uses the information on the RNA to produce proteins

13. mRNA leaves the nucleus and attaches to a ribosome
tRNA will bring amino acids to the ribosome
Anticodons on the tRNA will attach to the codon of mRNA linking the amino acids together in the correct order

17. protein synthesis video