Genotype vs Phenotype
Biology: AQA GCSE Higher, topic 6.1.16
Genotype vs Phenotype
When talking about the inheritance of characteristics, we use the words genotype and phenotype:
Genotype
- Genotype refers to the combination of alleles an organism has.
- If the two alleles are different, we say that the person is heterozygous (Bb).
- If the two alleles are the same, we say that the person is homozygous (BB or bb).
Phenotype
- A phenotype is an observed characteristic of an individual.
- The phenotype is determined by the interaction between the genotype and environment.
- Earlobes being attached or free is an example of a phenotype, where the alleles present will determine a characteristic, unless the environment interferes.
Test yourself on Genotype vs Phenotype
A person's genotype would normally give them free earlobes, but an injury means their earlobes look attached instead. What does this show about phenotype?
A person is homozygous recessive for earlobe shape, with the allele 'e' producing attached earlobes. If the environment does not interfere, what earlobe phenotype will they show?
A gene has two alleles, G (dominant) and g (recessive). A person has the genotype 'gg'. What type of genotype is this an example of?