A homozygous recessive allele combination contains two recessive alleles and expresses the recessive phenotype. For example, the gene for seed shape in pea plants exists in two forms, one form (or allele) for round seed shape (R) and the other for wrinkled seed shape (r).
What is an example of homozygous recessive?
Homozygous means that the organism has two copies of the same allele for a gene. … For example, pea plants can have red flowers and either be homozygous dominant (red-red), or heterozygous (red-white). If they have white flowers, then they are homozygous recessive (white-white). Carriers are always heterozygous.
Is BB An example of homozygous recessive?
Finally, the genotype of an organism with two recessive alleles is called homozygous recessive. In the eye color example, this genotype is written bb.
What traits are homozygous?
When a particular gene has identical alleles (versions) of chromosomes inherited from both parents, the gene is homozygous. A homozygous trait is referred to by two capital letters (XX) for a dominant trait, and two lowercase letters (xx) for a recessive trait.
Is TT homozygous dominant?
When an organism has two of the same alleles for a specific gene, it is homozygous (homo means “same”) for that gene.
Genotype and Phenotype.
|Heterozygous||One dominant allele and one recessive allele||Tt|
|Homozygous dominant||Two dominant alleles||TT|
|Homozygous recessive||Two recessive alleles||tt|
What are 3 heterozygous examples?
As a second example of a heterozygous trait, consider human blood types. The three allele possibilities are types A, B and O. A and B are codominant; O is recessive. The heterozygote AO gives type A blood, while BO gives type B blood.