Central Dogma
What does transcription produce from a DNA template?
RNA
Does RNA polymerase need a primer to start?
No
True or False – All codons correspond to an amino acid.
False (stop codons do not).
What is the role of tRNA?
It carries amino acids to the ribosome.
In eukaryotes, what helps the ribosome recognize the start codon?
The 5′ cap.
Which strand of DNA is used during transcription?
The template strand
In which direction does RNA polymerase synthesize RNA?
5′ → 3′
What amino acid does the start codon (AUG) code for?
Methionine (Met)
What is the name of the triplet on tRNA that base-pairs with codons?
Anticodon
In prokaryotes, what sequence must precede AUG to signal initiation?
A specific ribosome-binding sequence (Shine-Dalgarno sequence).
Which base in RNA replaces thymine (T) from DNA?
Uracil (U)
Which way does RNA polymerase move along the DNA template?
3′ → 5′
Name any of the three stop codons.
UAA, UAG, UGA
How many different aminoacyl-tRNA synthetases exist?
20 (one for each amino acid).
What proteins help in translation initiation?
Initiation factors.
What enzyme is responsible for making RNA?
RNA polymerase
How many RNA polymerases do bacteria have?
1
Why are there more codons than amino acids?
Because multiple codons can code for the same amino acid (redundancy/degeneracy).
In what orientation do codons and anticodons base pair?
Antiparallel orientation.
During elongation, where are amino acids added on the polypeptide?
The C-terminus.
True/False – Both DNA strands are transcribed into RNA.
False (only one strand is used)
Name one difference between bacterial and eukaryotic RNA polymerase.
Bacteria = 1 type; Eukaryotes = 2 or more
How many possible codons exist in the genetic code?
64 This total is calculated as 4^3, representing the four types of nucleotides (A, U, G, C)
What ensures that tRNA carries the correct amino acid?
Aminoacyl-tRNA synthetase specificity.
What enters the A site when a stop codon is reached?
A release factor.