The variation seen in facial features of an Inuit person from Canada, a person from Japan and a person from Sweden are examples of:

• biochemical variation.

• behavioural variation.

• intraspecific variation.

• interspecific variation.

Which of the following best describes an allele?

• A section of DNA found on a plasmid

• A physical characteristic that is inherited

• A combination of phenotypes

• An alternative version of a gene

Which of the following contribute to genetic variation?

• Crossing over and sexual reproduction

• Asexual reproduction and mutations

• Asexual reproduction and environmental change

• Mitosis and random fertilisation

Mutations are changes to DNA. A spontaneous mutation usually occurs:

• in transcription.

• when DNA is replicating.

• in transcription or translation.

• in reverse transcription.

Which of the following statements about mutations is true?

• They are permanent changes in the DNA sequence.

• They are mostly beneficial.

• They can be caused by the individual’s environment.

• The rate of mutations is influenced by the size of the genome.

Which of the following is probably not a mutagen?

(a mutagen is an agent that causes mutations)

• Radiation, including X-rays

• Cow’s milk

• UV light

• Benzene, an industrial solvent

The simplest form of mutation in DNA is a point mutation. Which of the following types of point mutation would have the greatest effect?

• A point mutation in the non-coding region of a chromosome

• A silent mutation

• A missense mutation

• A nonsense mutation

Cystic fibrosis (CF) is a genetic disorder that causes difficulty breathing, poor growth and a build-up of mucous in the lungs. The most common cause of CF is a deletion of three nucleotides from chromosome 7, which results in the loss of one amino acid. CF is an example of a:

• frameshift mutation.

• missense mutation.

• nonsense mutation.

• neutral mutation.

Which of the following is true for monoploidy?

• Female wasps and ants are often monoploid.

• It increases genetic variation.

• Monoploid individuals develop from unfertilised eggs, so they are sterile.

• Monoploid individuals develop from fertilised eggs, so they are fertile.

Bananas and watermelons have been produced where the plants are triploids. The result is fruit with no seeds, which is of great benefit to farmers. Which of the following is true of triploids?

• Meiosis is unaffected.

• Mitosis and meiosis are unaffected.

• They are 3n and normally sterile.

• They have three copies of a single chromosome.