AP BIOLOGY

Detailed explanation-1: -Hairless stems are present in tomato plants that are homozygous recessive for this trait. If the stem characteristics are determined by a single gene, what is the expected outcome of crossing two tomato plants that are heterozygous for hairy stems? Answers: A:75% hairy stems 25 hairless stems.

Detailed explanation-2: -Tomato plants usually have hairy stems. Hairless stems are present in tomato plants that are homozygous recessive for this trait.

Detailed explanation-3: -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.

Detailed explanation-4: -A karyotype test checks the chromosomes in your cells to: See whether you have a full set of 46 chromosomes. Having too many or too few chromosomes can cause serious problems with health, growth, and normal development, such as Down syndrome (extra chromosome 21) and Turner syndrome (missing X chromosome).

Detailed explanation-5: -A homozygous dominant individual has two of the same dominant alleles for a gene. For example, a plant that is homozygous dominant for the red flower color allele has the genotype RR.