Genetics: Key terms Flashcards
Test review
What is genetics?
The study of heredity
What is heredity?
The passing of traits from one generation to the next
What are traits?
Inherited characteristics (Eg; Hair & Eye colour or behaviour/instincts)
What is a genotype?
Particular combinations of alleles an organism has (Eg; TT, tt, Tt)
What is a phenotype?
Physical or visible features determined by genotypes (Eg; Tall or short)
What does it mean to be homozygous?
Organism contains the same two alleles for a trait (Eg; TT or tt)
What does it mean to be heterozygous?
Organism contains two different alleles for a trait
(Eg; Tt)
What is polygenic inheritance?
Traits are controlled by 2 or more pairs of genes. They show much variation.
(Eg; Height, skin and eye colour)
What are sex linked genes?
Genes which carry only on the X chromosome
What are sex linked traits?
Traits determined by sex linked genes
Examples:
Humans - RG colourblindness, Hemophilia
Fruit flies- Eye colour
What are genes?
The basic unit of inheritance. A very specific part of a chromosome with specific DNA.
What are alleles?
Alternative forms of genes (Eg; T and t are height alleles in pea plants)
