[05] Genetic Code Flashcards
What is the genetic code?
The set of rules by which information encoded in genetic material (DNA or RNA sequences) is translated into proteins (amino acid sequences) by living cells.
How many nucleotides make up a codon?
Three
What does each codon in the genetic code represent?
A specific amino acid
What are start and stop codons?
Start codons → signal the start of translation and the amino acid methionine
Stop codons → signal the end of translation
What is the start codon?
AUG
List the stop codons.
- UAA
- UAG
- UGA
What does it mean that the genetic code is degenerate?
More than one codon can specify the same amino acid
How is the genetic code read?
It’s read in triplets of nucleotide bases, known as codons
GC - Initials
Genetic Code
Can the genetic code vary between organisms?
It’s largely universal but there are few exceptions
Is the genetic code overlapping?
No, each nucleotide is part of only one codon
What’s the role of tRNA in the genetic code?
tRNA molecules carry amino acids to the ribosome based on the codon in the mRNA
Is the genetic code conservative or evolving?
It’s conservative; changes would lead to drastic changes in protein sequence
What’s an anticodon?
A sequence of three nucleotides forming a unit of genetic code in a tRNA molecule, corresponding to a complementary codon in mRNA
How many possible codons are there in the genetic code?
64
How many of the codons code for amino acids?
61
How many amino acids are coded by the genetic code?
20
Is the genetic code the same for all organisms?
It is nearly universal, with very few exceptions
What is the relationship between the genetic code and protein synthesis?
The genetic code dictates the sequence of amino acids in proteins during protein synthesis
Which molecule serves as the template for the genetic code during protein synthesis?
mRNA
