S5 Bio - Ch19 Unit Test (Term 2)

What is a mutation?

[1 point]

• A change in a gene or chromosome

• A condition caused by a dominant allele

• A process used in genetic engineering

• A type of continuous variation

Which characteristic shows a discontinuous variation in humans?

[1 point]

• height

• length of foot

• tongue rolling

• weight

A man who was blood group A and a woman who was blood group B had four children, each with a different blood group A, B, AB, and O. Which type of variation does this demonstrate?

[1 point]

• continuous, environmental, and genetic

• continuous and genetic only

• discontinuous, environmental, and genetic

• discontinuous and genetic only

What is not a feature of natural selection?

[1 point]

• competition for resources

• production of many offspring

• selection by humans

• variation within the population

Cacti have fewer stomata than other plants. How does this help them to survive in desert conditions?

[1 point]

• It increases the loss of water.

• It increases the uptake of carbon dioxide.

• It reduces the loss of water.

• It reduces the uptake of carbon dioxide.

The graph shows the masses of two different types of tomato. What can be concluded from the graph?

[1 point]

• Type 1 tomatoes show continuous variation.

• Type 2 tomatoes show discontinuous variation.

• Type 2 tomatoes are sometimes smaller than type 1 tomatoes.

• Genes do not affect the mass of tomatoes.

What is meant by stabilising selection?

[1 point]

• The population will lose the entire poorly adapted individual.

• Maintains the same characteristics in a population.

• The action or fact of carefully choosing someone.

• none of the options

Which name is given to the observable features of an organism?

[1 point]

• alleles

• genes

• genotype

• phenotype

It is a condition caused by a codominant allele of the gene that codes for haemoglobin.

[1 point]

• selective breeding

• MRSA

• fitness

• sickle cell anaemia

What is a mutagen?

[1 point]

• A change in the base sequence of DNA.

• A substance that causes mutation.

• A genetic disease.

• A genetic change.