AP BIOLOGY

Detailed explanation-1: -In this case, the first parent is homozygous recessive. Thus, their genotype would be tt. Their phenotype would be short. The second parent is heterozygous, so their genotype would be Tt, and their phenotype would be tall.

Detailed explanation-2: -An organism can be either homozygous dominant ( TT ) or homozygous recessive ( tt ). If an organism has two different alleles ( Tt ) for a certain gene, it is known as heterozygous (hetero-means different).

Detailed explanation-3: -In F2 generation, the tall and dwarf plants will be produced in 3 : 1 ratio. Out of the three tall plants, one tall plant will be homozygous tall (TT) and two tall plants will be heterozygous tall (Tt).

Detailed explanation-4: -How do you write the alleles for a homozygous recessive genotype? When writing the alleles for a homozygous recessive genotype two lower case letters would be used. For example, when breeding pea plant, if the trait for short plants was recessive (t) the homozygous recessive genotype would be written as tt.

Detailed explanation-5: -Pea plants are tall if they have the genotype TT or Tt, and they are short if they have genotype tt. A tall plant is mated with a short plant.