Variation selection

The table shows the birth rates and death rates in four countries. Which country will double its population most quickly?

The bar chart shows the heights of pea plants grown from 500 pea seeds. What variation do the plants show?

In arthropods, growth occurs only after the exoskeleton is shed and before the new one hardens. Which graph shows a typical growth curve for an arthropod?

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

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?

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

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

• alleles

• genes

• genotype

• phenotype

Which is a sudden change in a gene or chromosome?

• allele

• genotype

• mutation

• phenotype

What is an example of a characteristic that shows discontinuous variation in humans?

• blood group

• body mass

• height

• width of hand

The diagram shows the age structure of a human population. Which age group has the largest number of people?

• 60 and over

• 45 – 59

• 30 – 44

• under 15