A polypeptide has the following amino acid sequence:
alanine - alanine - valine - lysine - valine - serine
The table below gives the base sequences for the DNA triplets of each amino acid.
| Amino acid |
DNA triplet |
| serine |
TCG |
| valine |
GTA |
| lysine |
AAA |
| alanine |
GCT |
| stop |
TAA |
A mutation in the DNA coding for this polypeptide chain caused the tenth nucleotide to change from an A to a T.
Which of the following would represent the amino acid sequence in the polypeptide after the mutation occurred?
alanine - alanine - valine - lysine - valine - serine
alanine - alanine - valine - stop - valine - serine
alanine - alanine - valine
alanine - alanine - valine - serine - valine - serine
Which of the following processes involve both DNA and RNA?
I. Replication
II. Transcription
III. Translation
IV. Protein synthesis
The following steps are involved in the process of replicating DNA by polymerase chain reaction (PCR).
- The temperature is increased to 72°C to allow Taq polymerase to bind to DNA
- A new complementary strand of DNA is produced
- The temperature is raised to 95°C to cause denaturation of the DNA molecule
- Primers attach to the ends of single strands of DNA by hydrogen bonding
- The temperature is decreased to about 54°C
Which of the following represents the correct order of the steps?
A short section of mRNA that was produced after transcription occurred has the following base sequence:
AAACUUCUCAUAGAACGG
The following table shows the base sequence for codons and the corresponding amino acids that they code for.
Which of the following would represent the correct amino acid sequence coded for by this section of mRNA?
Lysine - Leucine - Proline - Asparagine - Glycine - Alanine
Lysine - Phenylalanine - Proline - Lysine - Glycine - Alanine
Lysine - Leucine - Threonine - Asparagine - Arginine - Arginine
Lysine - Leucine - Proline - Asparagine - Arginine - Alanine
A polypeptide has the following amino acid sequence:
histidine - glutamine - lysine - alanine - valine - histidine - valine
The table below gives the tRNA anticodons for each amino acid.
| Amino acid |
tRNA anticodons |
| histidine |
CAU |
| valine |
GUA |
| lysine |
AAA |
| alanine |
GCU |
| glutamine |
CAG |
A mutation causes the 18th base in the DNA sequence to be deleted.
Which of the following would represent the amino acid sequence after this deletion?
histidine - glutamine - lysine - alanine - valine - histidine
histidine - glutamine - lysine - alanine - valine
histidine - glutamine - lysine - alanine - valine - glutamine
histidine - glutamine - lysine - alanine - valine - histidine - valine
