Transcript Translation - Phillipsburg School District

Translation
Translation
• Converts/transfers information from mRNA into
amino acids
• Amino acids are the monomers of proteins
• String amino acids together and a protein is made
• 3 RNAs needed
– mRNA (messenger—from nucleus to ribosome)
– rRNA (ribosomal—used in the ribosome)
– tRNA (transfer—transfers the codons into amino acids
using anticodons)
Translation
3 Main Steps
1. Initiation
• mRNA attaches to the ribosome (with the use
of rRNA)
• rRNA reads the mRNA in groups of 3
nucleotides called codons
• Translation starts with a special codon
– AUG—start codon—initiator
Translation
3 Main Steps
2. Elongation
• tRNA carries specific amino acid to the ribosome
• The specific amino acid is determined by the
anticodon of tRNA
• The anticodon pairs with complementary codon
on mRNA (Example: codon AUG; anticodon UAC)
• Peptide bonds form between amino acids, linking
them into proteins
• tRNAs get recycled back to go pick up more
amino acids
Translation
amino acid
tRNA
**Draw this!
anticodon
codon
protein
(linked amino acids)
ribosome
Translation
3 Main Steps
3. Termination
• Protein is released from ribosome when “stop
codon” is reached
– 3 stop codons:
• UAA
• UAG
• UGA
1.
mRNA codon chart
Let’s Try!!
1. If mRNA codon is CCG,
what is the amino acid?
2. If tRNA anticodon is AAC,
what is the mRNA codon?
What is the amino acid?
3. If the DNA template
strand is ATA, what is the
mRNA codon?
What is the amino acid?
2.
3.
Translation Answers
1. Proline
2. UUG ; leucine
3. UAU ; tyrosine
Now….
1. Use codon chart to complete practice worksheet
2. Draw/analyze/explain Figures:
17.12
17.15
17.16
17.23