Table of Contents
- 1 When two pea plants that are heterozygous for yellow peas are crossed the resulting offspring have a phenotypic ratio of?
- 2 What phenotypes are produced when homozygous yellow peas are crossed with homozygous green peas?
- 3 How many of the offspring will also be heterozygous?
- 4 What ratio of yellow to green seed color would you expect among the offspring?
When two pea plants that are heterozygous for yellow peas are crossed the resulting offspring have a phenotypic ratio of?
The P cross produces F1 offspring that are all heterozygous for both characteristics. The resulting 9:3:3:1 F2 phenotypic ratio is obtained using a Punnett square. In pea plants, purple flowers (P) are dominant to white (p), and yellow peas (Y) are dominant to green (y).
What happens when 2 heterozygous plants are crossed?
Plants with two different alleles of a gene are heterozygous. Since all the heterozygous offspring are yellow, then the yellow allele must be dominant over the recessive green allele. When two heterozygous plants are crossed, the resulting progeny mostly show the dominant phenotype.
What will be the phenotypes of the offspring of green seeds and yellow seeds?
Seed color is governed by a single gene with two alleles. The yellow-seed allele is dominant and the green-seed allele is recessive. That is, the hybrid offspring were phenotypically identical to the true-breeding parent with yellow seeds.
What phenotypes are produced when homozygous yellow peas are crossed with homozygous green peas?
Homozygous green peas were crossed with homozygous yellow peas. All the offspring were phenotypically yellow.
What offspring is produced if a heterozygous tall pea plant is cross with a homozygous short pea plant?
The “TT” and “Tt” crosses both have at least one “T” allele, so they are tall plants. However, the last cross “tt” doesn’t have any “T” alleles and is short, because it is homozygous recessive . Since 1 out of 4 pea plants are short, or 1/4, the probability of a short pea plant from a heterozygous cross is 25%.
What is the probability of having offspring that is heterozygous for yellow seeds?
25% of seeds are homozygous YELLOW, 50% are heterozygous, and 25% are homozygous green. This is a 1:2:1 genotypic ratio.
How many of the offspring will also be heterozygous?
On average, half of the children will be heterozygous (Aa) and, therefore, carriers. The remaining half will inherit 2 recessive alleles (aa) and develop the disease. It is likely that every one of us is a carrier for a large number of recessive alleles.
Why are peas green if yellow is dominant?
Turns out they have yellow peas because the yellow version, Y, is dominant over the recessive green version, y. Y always wins out over y: When a pea plant makes seeds, only one of its two copies of the color gene goes into the seed. So if you have two green pea plants, each can only pass a green version.
What is the genotype of yellow?
YY is the homozygous dominant genotype (2 Y alleles). The phenotype of this genotype is yellow seed color. Yy is the heterozygous genotype (one dominant allele, one recessive allele). The phenotype of this genotype is yellow seed color.
What ratio of yellow to green seed color would you expect among the offspring?
There are 2 phenotypes. 75% of seeds will be YELLOW. 25% of seeds will be green. This is a 3:1 phenotypic ratio.
When an individual heterozygous for a trait is crossed with an individual homozygous recessive for the trait the offspring produced will?
|When an individual heterozygous for a trait is crossed with an individual homozygous recessive for the trait, the offspring produced will?||All have the same genotype|
|If a characteristic is sex-linked, the gene for it is found on?||A Sex chromosome|
What happens when a heterozygous pea plant is crossed with another tall heterozygous pea plant?
Do you know where each letter (allele) in all four cells comes from? Two pea plants, both heterozygous for flower color, are crossed. The offspring will show the dominant purple coloration in a 3:1 ratio. Or, about 75% of the offspring will be purple.