After reading the prompt, can you answer these questions about genetic crosses? A trait may not show up in an individual but may still be passed on to the next generation. Mendel is describing the recessive trait. In the F1 generation, each parent would provide gametes containing either the dominant or recessive allele, but not both. The heterozygous condition would produce equal amounts of yellow and green seeds. Imagine you are looking out at a field of flowers. 774 plants have red flowers; 226 plants have white flowers. Based on Mendel's work, the parents are heterozygous for flower color. We would describe the genotype for green seeds as homozygous recessive. Consider a field of pea plants that produce half green and half yellow seeds. The genotype of each parent must be Yy.

Question

Biology

Edith Bonilla

14 October, 23:06

After reading the prompt, can you answer these questions about genetic crosses? A trait may not show up in an individual but may still be passed on to the next generation. Mendel is describing the recessive trait. In the F1 generation, each parent would provide gametes containing either the dominant or recessive allele, but not both. The heterozygous condition would produce equal amounts of yellow and green seeds. Imagine you are looking out at a field of flowers. 774 plants have red flowers; 226 plants have white flowers. Based on Mendel's work, the parents are heterozygous for flower color. We would describe the genotype for green seeds as homozygous recessive. Consider a field of pea plants that produce half green and half yellow seeds. The genotype of each parent must be Yy.

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Sam Rogers · Answer 1

1. It is true that the trait may not show up in an individual but may still be passed on to the next generation. That happens when the dominant allele masks the recessive one. For example in genotype Aa (heterozygous) only the A phenotype is expressed. But, if both parents pass the recessive alleles, the offspring will have aa genotype (recessive homozygous) and that trait will be showed up. Each parent provide gametes containing either the dominant or recessive allele, but not both meaning that in the offspring one allele is inherited from father and one from mother.

According to Mendelian genetics, the heterozygous condition would produce yellow seeds, because it is dominant over green.

2. Lets say that the gene for flower color is A. The genotype of the parents is heterozygous (dominant and recessive alleles) Aa.

P: Aa x Aa

F1: AA Aa Aa aa Ratio is 3:1for the dominant phenotype. Since there is 774 plants with red flowers and 226 plants with white flowers, this means that the red phenotype is dominant over white flower phenotype.

Red flower genotypes are AA (homozygous dominant) and Aa (heterozygous).

White flower genotype is aa (homozygous recessive).

3. If genotype for green seeds is homozygous recessive that means that is has two recessive alleles (yy). The genotype of each parent is Yy.

P: Yy x Yy

F1: YY Yy Yy yy

If we cross pea plants with green seeds (yy) with pea plants with yellow seeds that are heterozygous (Yy):

P: yy x Yy

F1: Yy yy Yy yy Half of them is with yellow seeds and other half is with green seeds.