Biology 120 Notes (Part 18) Continuing Genetics

Testcross

is a process that is used to assess whether an individual displaying a dominant trait is heterozygous or homozygous.

F1

Mendel allowed the progeny to self- pollinate and the wrinkled seed trait reappeared in the F2 generation.

Testcross

is a process that is used to assess whether an individual displaying a dominant trait is heterozygous or homozygous.

F1

Mendel allowed the progeny to self- pollinate and the wrinkled seed trait reappeared in the F2 generation.

Gregor Mendel

worked with pea varieties that differed in seven easily recognizable traits, this can also be referred to as an individuals phenotype (a trait that can be observed .)

True breeding

is a term that describes how all of the offspring are of the same variety.

Alleles

can be dominant or recessive.

Genotype

refers to the two alleles an individual has for a specific trait.

Genetic disorders

can be either autosomal or sex- linked.

Mendels

pea population had two distinct phenotypes for each of the seven traits.

Mendel

crossed plants with round seeds and plants with wrinkled seeds.

A trait is a variant for a character, for example

brown

We label the different generations of a cross as

P generation (parents), F1 generation (first filial generation), and F2 generation (second filial generation)

The two possible results were

the F2 generation with two phenotypes (identical to the parents) or the F2 generation with four phenotypes

Phenotype

refers to a trait that can be observable.

trait

A _ is a variant for a character

monohybrid cross

A __ describes the mating between two parents that differ in only one trait.

law of segregation

The ____ describes how each individual has a pair of factors for each trait called alleles. The alleles segregate during gamete formation.

The two possible results of a dihybrid cross are:

the F2 generation with two phenotypes (identical to the parents) or the F2 generation with four phenotypes.

autosomal recessive disorders

To have an __, the individual who has it would have homozygous recessive alleles (aa).

autosomal dominant disorder

The individual who has an _ would either have to have AA or Aa.

Sex-linked disorders

_ affect the X and Y chromosomes.

Autosomal disorders

affect autosomes.