Lecture 3
No description yet. This curated deck is ready for daily study.
Card preview (17)
Where does translation and Transcription happen?
• Transcription in nucleus • Translation in cytoplasm
General Structure of amino acid
Glycine, methionine and Lysine
How does a peptide bond work
A bit about the genetic code
• 3 bases code for 1 amino acid (triplet code) • 64 amino acids • therefore the 20 amino acids can form
How to convert RNA into a protein
Amino acids grouped off their biochemical / structural properties
Know the red arrowed ones
Essential vs Non essential amino acids
You need to know how to draw these 9 highlighted amino acids
What are reading frames?
DNA is double stranded, so there are 3 possible frames on the 2nd strand. ALWAYS READS 5’ TO 3’. An open frame is a run of codons starting with ATG and ending with a termination codon TGA, TAA or TAG, AND GIVES US THE LONGEST PEPTIDE.
Which reading frames are open?
A run of codons starting with ATG and ending with a termination codon TGA, TAA or TAG AND GIVES US THE LONGEST PEPTIDE. Still always 5’ to 3’. Same principle applies for 2nd and 3rd reading frame. Always have N - met at the start, and - C for the final codon. NEVER START OR STOP.
What is meant by ‘triplet code’
Each triplet of bases on a DNA strand codes for a SPECIFIC amino acid in the RNA when it is translated.
What is degeneracy in the genetic code?
What does non-overlapping mean?
Adjacent codons do not overlap, so no base can take part in the formation of more than 1 codon
What is non-ambiguity?
Sane codon cannot code for 2 or more amino acids in a sequence of RNA DESPITE DEGENERACY.
What does universal mean in genetic code?
Same sequence of 3 bases codes for the same amino acids in all life forms
What is polarity in the genetic code?
When reading RNA, IT IS ALWAYS READ IN A 5’ TO 3’ DIRECTION