Characteristics can be examples of continuous or discontinuous variation.

Write the four characteristics below in the correct columns of the table:

• Diastolic blood pressure
• Cleft chin
• Foot length
• Tongue-rolling ability

Identical twins in sheep occur when an embryo splits into two.

In the diagram below, some of the chromosome numbers in the different cells have been given to you.

Draw on this

Complete the diagram to show the number of chromosomes in:

• The sperm cell
• The zygote
• The cell in Lamb Y's body.