Homozygous means that the organism has two copies of the same allele for a gene. An organism can be homozygous dominant, if it carries two copies of the same dominant allele, or homozygous recessive, if it carries two copies of the same recessive allele.
What alleles is homozygous recessive?
An organism with one dominant allele and one recessive allele is said to have a heterozygous genotype. In our example, this genotype is written Bb. Finally, the genotype of an organism with two recessive alleles is called homozygous recessive. In the eye color example, this genotype is written bb.
How do you represent homozygous recessive?
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.
Can you have a heterozygous recessive?
No, there cannot be heterozygous recessive state. Any trait or characteristic is determined by gene that exists in two alternative forms called alleles, one is dominant allele and the other is recessive allele.
Is AA homozygous dominant?
Homozygous means that both copies of a gene or locus match while heterozygous means that the copies do not match. Two dominant alleles (AA) or two recessive alleles (aa) are homozygous. One dominant allele and one recessive allele (Aa) is heterozygous.
What gametes can be produced by TT?
The plant with the RR:TT genotype produces haploid sex gametes that have the genes R:T. The plant with the rr:tt genotype produces haploid sex gametes that have the genes r:t. At fertilization, two of these sex gametes fuse.
Which allele is always written first?
The alleles are represented by letters. The letter chosen is usually the first letter of the trait.