Aplant breeder is trying to develop a deep purple violet. she knows the violets come in deep purple, light purple, and white. she crosses two violets hoping to produce only the deep color. which parent plants should she use?

She should use two deep-purpled plants, PP.

Explanation:

The exposed example might be a case of incomplete dominance. Incomplete dominance is a condition where neither of the alleles completely dominates over the other one. Dominant alleles cannot completely cover up the recessive alleles. Descendents possess an intermediate phenotype between the two parental phenotypes and not the dominant one, which would appear if this would be the case of complete dominance.

In the example, deep-purple violet (Genotype PP) and white violet (Genotype pp) might be the homozygote plants, while light-purple violet (Genotype Pp) might be the heterozygote plant -the intermediate phenotype-.

If the plant breeder wants to produce only deep-purple violets, she needs to cross deep-purple flowers to get 100% homozygote plants for that color. This is:

an individual’s sex (i.e., whether they are a male or female) is determined by the sex chromosomes. most people have two sex chromosomes, one that is inherited from their mother and one that is inherited from their father. typically, females have two x chromosomes (xx) and males have one x chromosome and one y chromosome (xy). conditions caused by changes (“mutations”) in genes located on the x chromosome are considered x-linked.

x-linked recessive inheritance

most x-linked conditions are recessive. this means that in a person with two x chromosomes (most females), both copies of a gene (i.e., one on each x chromosome) must have a change or mutation whereas in a person with one x chromosome (most males), only one copy of a gene must have a mutation. a female with a mutation in one copy of a gene on the x chromosome is said to be a “carrier” for an x-linked condition. a male with a mutation in a gene on the x chromosome is typically affected with the condition. because females have two copies of the x chromosome and males have only one x chromosome, x-linked recessive diseases are more common among males than females. however, x-linked recessive diseases can occur in both males and females.

for x-linked recessive disorders, an unaffected carrier mother who has a mutation in a gene on the x chromosome can transmit either the x chromosome with this mutation or a “normal” x chromosome to her children. if the father is unaffected, none of her daughters will be affected and all of her daughters will be unaffected—since they will inherit at least one normal x chromosome from their father. however, each daughter will have a 50% chance of being an unaffected carrier like her mother and a 50% chance of both x chromosomes being normal.

a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.