What is the difference fom heterozygous and homozygous recessive?

Answer 1

In genetics, you can either have a dominant allele (A) or a recessive allele (a). Being homozygous means that you have both of either a dominant or a recessive allele (ie you are either AA or aa). If the trait is a recessive trait, then you need to have it be homozygous recessive in order to express that trait. Hope this was helpful! :-)

Answer 2

There is no such thing as heterozygous dominant or recessive. Heterozygosity is the combination of a dominant and a recessive allele. There is something called autosomal (or X-lined) dominance or recessive, which defines which allele expresses itself when an individual is heterozygous for a particular locus. For example, if Aa individual "looks like" AA individual, then the locus is autosomal dominant. If Aa "looks like" aa individual, then the locus is autosomal recessive.

Answer 3

In simple mendelian genetics a recessive trait can only be expressed if there are two copies of the recessive trait at the gene locus of both chromosomes.

A heterozygous recessive individual carries both the dominant and recessive alleles so the dominant characteristic is expressed.

Lets say that red (R) is dominant and black (r) is recessive. In order for an animal to

be red it can be homozygous dominant (RR) or heterozygous (Rr). Only an animal with the homozygous recessive genetics (rr) will be black.

What a plant or animal looks like is called phenotype...so it is phenotypically red or black in this example. Two phenotypes.

The genotype is the genetic make up of the individual RR, Rr or rr. Three genotypes.

An RR individual crossed with any other type of individual will produce only Red offspring. An rr individual crossed with another rr individual will produce only black offspring.

Other crosses

Rr X rr will produce 50% rr (black) and 50% Rr (Red) offspring

Rr X Rr will produce 25% RR (Red) 50% Rr (Red) and 25% rr (black)

Answer 4

they are both homozygous or have the same type of allele for both in the genotype.

Answer 5

homozygous is dominant and hetrozygous is recssive, it does not depends on anything

Answer 6

dominant is upper case and recessive is lower case

Answer 7

Homozygous Dominant, or AA is two alleles for a trait that are both dominant

Homozygous Recessive, or aa is two alleles for a trait that are both recessive