Mutations & Gene Editing (HL IB Biology)

A base substitution mutation has caused a single change to the mRNA transcript of a section of a gene, as shown below. 

Original sequence	AUGGAAAUACCGCCAGGA
Mutated sequence	AUGGAAAUACUGCCAGGA

Using the table above, what is the change in amino acid sequence caused by this mutation?

The risk of developing a cancerous tumour is increased by exposure to which of the following?

	Ultraviolet light	Benzo[a]pyrene	Carbon monoxide	X-rays
A.	✓	✓	✗	✓
B.	✓	✗	✗	✓
C.	✗	✓	✓	✗
D.	✓	✗	✓	✗

Key: ✓ = increases risk, ✗ = does not increase risk

Sickle cell anaemia is caused by the following mutation in the gene that codes for haemoglobin:

Which of the following correctly explains how this mutation causes sickle cell anaemia?

The nucleotide base sequence and the associated sequence of four amino acids can be seen below:

AGG   ACA   CCT   GGA

Serine   Tyrosine   Glycine   Proline

The table shows the mRNA codons and their associated amino acids.

A single mutation occurred in the original base sequence of the DNA which resulted in only one amino acid from the sequence being produced.

Which of the following would represent the correct nucleotide base sequence which was found in the DNA after the mutation occurred?