1. 12-3: RNA and Protein Synthesis (part 1)

2. The Structure of RNA
Same structure as DNA except: it has ribose, is single stranded and thymine is replaced by uracil.
A-U, C-G for RNA
A-T, C-G for DNA

3. Types of RNA most RNA is involved in protein synthesis. three types:
1. messenger RNA (mRNA): a copy of a gene from DNA that serves as instructions for assembling amino acids into a protein.
2. ribosomal RNA (rRNA): a structural component of ribosomes along with proteins.
3. transfer RNA (tRNA): a molecule that transfers amino acids into the ribosome.

4. Transcription
transcription: copying part of a nucleotide sequence of DNA into a complimentary sequence of RNA
RNA polymerase required
binds to the DNA and separates strands
uses one strand as template for assembling nucleotides of RNA

6. RNA Editing some RNA must be trimmed and cut to final sizes
introns: pieces of RNA removed before the RNA becomes functional
exons: remaining segments of RNA spliced together to form the final mRNA

8. The Genetic Code
The properties of proteins are determined by the sequence of its amino acids.
This sequence is determined by the order of nucleotides in the DNA that is transcribed into RNA.
RNA language:
uses 4 different letters (A, U, C, and G)
uses only three-letter words
codons: three consecutive nucleotides of mRNA that specify an amino acid

9. The Genetic Code 64 possible mRNA codons (4 x 4 x 4 = 64)
AUG is start codon that codes for methionine
This is always the first amino acid in all proteins!
Three stop codons signify the end of a protein (UAA, UAG, UGA)

10. Reading the genetic code (from mRNA):
AUG:
methionine
UCA:
serine
CCG:
proline
UAG:
Stop (this ends the protein)