RNA

1
RNA

• Stands for Ribose Nucleic Acid
• Single stranded
• Contains a ribose sugar
• Uracil instead of thymine, so adenine bases with
  uracil

2
RNAs Purpose

• To take information on how to build a protein and
  assemble amino acids accordingly
• How? Assembles amino acids in a long chain
  which is used to code for proteins

3
3 Types of RNA
NEED TO KNOW!!!!

• mRNA Messenger RNA brings information from
  the DNA in the nucleus to the cytoplasm
• rRNA Ribosomal RNA clamp onto the mRNA and
  use it to assemble the amino acids in the correct
  order
• tRNA Transfer RNA transports the amino acids
  to the ribosome to be assembled into a protein.

4
Transcription

• Process in the cell nucleus when enzymes make an
  RNA copy of a DNA strand
• Same process as DNA replication with some
  differences
• RNA molecule is single-stranded (rather than
  double stranded in DNA)
• Uracil instead of Thymine. So in RNA Adenine
  binds with Uracil

5
Transcription

• Where it takes place
• Prokaryotic cell in the cytoplasm
• Eukaryotic cell in the nucleus, then it moves
  to the cytoplasm

6
Transcription
A G CTTAGCAGC
T CGAATCGTCG
U CGAAUCGU CG
DNA backbone
DNA backbone
mRNA
7

• We know that amino acids are the building
  blocks for proteins
• But how do we get amino acids from mRNA?

8
The Code

• Biochemists started to break the genetic code
  when they realized that 3 nucleotides code for an
  amino acid!
• This is known as a CODON
• Amino acids are considered the code that converts
  the language of mRNA to our proteins

9
The Code.

• 20 amino acids total
• 64 different mRNA codons in the genetic code
• All organisms have the same genetic code for
  amino acids and proteins
• Important Codons
• Start AUG
• Stop UAA, UAG, UGA

10
Amino Acid Chart
11
How to Read the Amino Acid Chart

• Start on the left side with the first letter of
  the codon
• Then find the second letter of the codon along
  the top of the chart
• Then, on the right side, find the corresponding
  last letter of the codon

12
You Try It!!

• Which amino acid do the following codons code
  for?
• CUU
• GAC
• UAC
• CAU
• UAG
• UGA

• Which codons would code for the following amino
  acids?
• Methionine
• STOP
• Glycine
• Arginine
• Histine
• Proline