Alleles (Edexcel GCSE Biology Combined Science): Flashcards
📚Flashcards
Practise the cards
10 cards from this deck
ShowHide
Practise the cards
10 cards from this deck
What are alleles?
What are alleles?
Different versions of the same gene
How many alleles per gene in an individual?
How many alleles per gene in an individual?
Two - one from each parent
What does homozygous mean?
What does homozygous mean?
Both alleles are the same
What does heterozygous mean?
What does heterozygous mean?
Two alleles are different
What is a genotype?
What is a genotype?
The combination of alleles an individual has for a particular gene
What is a phenotype?
What is a phenotype?
The physical expression of a trait
What is a dominant allele?
What is a dominant allele?
An allele that is always expressed, even if only one copy is present
How are dominant alleles represented?
How are dominant alleles represented?
Capital letters (e.g., A)
When is a recessive allele expressed?
When is a recessive allele expressed?
Only when two copies are present
How are recessive alleles represented?
How are recessive alleles represented?
Lowercase letters (e.g., a)