Inheritance

Whats infraspecific variation?

when organisms of the same species have different characteristics

Whats genetic variation?

the differences in the DNA of organisms in the same species

What are the types of intraspecific variation?

genetic variation and phenotypic variation

What causes genetic variation?

genetic factors

When does genetic variation occur?

meiosis and sexual reproduction

Whats phenotypic variation?

differences in phenotypes between organisms of the same species

What causes phenotypic variation?

environmental and genetic factors

Etiolation?

when plants aren’t exposed to light so have a pale green leaves and an elongated stem due to lack of chlorophyll production

What happens when a fruit fly is only given a diet of silver salts?

it appears yellow

Whats monogenic inheritance?

The inheritance of one gene

Whats a monogenic cross?

A cross in which there’s only two alleles represented, which only code for one gene

Whats dihybrid inheritance?

the inheritance of two genes

How do we look at dihybrid inheritance?

dihybrid crosses

Whats the chi-squared test used for?

studying categorical data like offspring phenotypes

Whats codominance?

when both alleles are expressed and neither are dominant or recessive

Whats an example of codominance?

AB blood types

Whats autosomal linkage?

When two or more genes appear on the same autosome

Whats an autosome?

any chromosome that isn’t a sex chromosome

What does autosomal linkage result in?

What does crossing over cause in autosomally linked genes?

a larger variety of possible parental genotypes

What is the ratio of autosomal linkage without crossing over?

3:1

Whats the ratio for your autosomal linkage with crossing over?

9:3:3:1

What are homologous pairs?

paired chromosomes in diploid cells which have the same gene loci but can have different or the same alleles for genes

What chromosomes do women have?

XX

what chromosomes do men have?

XY

What are sex-linked genes?

Genes which are located on a sex chromosome so allele expression depends on an individuals sex

Whats a carrier?

A parent who carries the allele but doesn’t have the trait

What do pedigree analysis diagrams show?

Inheritance of a particular phenotype over several generations

Whats epistasis?

When one gene affects the expression of another gene to determine a part of the phenotype

Whats an example of epistasis?

fur colour in mice as one gene, which is for the amount of melanin produced which affects fur colour, decides fur colour but another gene can caused this to be masked, which is whether the mice has produced melanin