What is an allele?

  1. In the nucleus of the cell, there are pairs of chromosomes which carry the same genes in the same places. 2) Alleles are different versions of these genes.3) For example, a person may have an allele for brown eyes on one chromosome and an allele for green eyes on the other. 4) Dominant alleles only require one copy for it to be expressed, whereas recessive alleles need two copies: they are only expressed if both alleles are recessive (no dominant alleles). 
ES
Answered by Ella S. Biology tutor

8314 Views

See similar Biology GCSE tutors

Related Biology GCSE answers

All answers ▸

Describe the structure of a human heart and how this enables it to bring blood carrying oxygen to the tissues of the body


What is an enzyme and how does it work?


How are veins and arteries adapted to the transport of blood?


|The diagram shows part of a DNA molecule. DNA is a polymer. What is the evidence from the diagram that DNA is a polymer?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning