U2 Variation Inheritance Flashcards
What is discrete variation?
Variation which is controlled by a single gene and can be sorted into distinct groups
What is continuous variation?
Variation which is controlled by multiple genes and can be placed along a scale
What is a gene?
Section of DNA which codes for a protein or amino acid
What is an allele?
The different forms of a gene
What is the phenotype?
The physical characteristic which is shown in a person
What is the genotype?
The alleles which an organism has for a characteristic, generally represented by letters e.g. Aa, AA, aa
Define homozygous.
When an organism has two of the same alleles for a characteristic
Define heterozygous.
When an organism has two different alleles for a characteristic
What is the P generation?
The first generation of a genetic-cross experiment
What is the F1 generation?
The first generation of offspring as a result of the P generation reproducing.
What is the F2 generation?
The second generation which comes as a result of two members of the F1 generation reproducing
What is a recessive allele?
An allele which phenotype will only show if it is homozygous
What is a dominant allele?
An allele which phenotype will always show as long as one of it is present
Why are predicted phenotype ratios not always accurate?
Fertilisation is a random event
