Answer:
The phenotypic ratio will be 3:1
Explanation:
As per this question there are two phenotypes for seed color, yellow and green. Both the parents are true breeding that means they are homozygous for this trait. Also, all the F1 plants have yellow seed color which clearly indicates that yellow seed color is a dominant trait while green is recessive trait.
The cross of true breeding plants as mentioned above is depicted as under:
Parents YY x yy
/ \ / \
F1 generation Yy Yy Yy Yy
So, as per the law of dominance because of the presence of Y allele, all these progeny will be yellow in color.
Next, when these F1 plants will be crossed, the result will be as under:
F1 generation Yy x Yy
/ \ / \
F2 generation YY Yy Yy yy
The genotypic ratio of F2 generation is 1:2:1
The phenotypic ratio of F2 generation is 3:1
It simply means that in F2 generation, 3 progeny which have allelic combination YY & Yy will be yellow colored while 1 progeny which has allelic combination yy will have green color.
Answer:
DNA is made of chemical building blocks called nucleotides. These building blocks are made of three parts: a phosphate group, a sugar group and one of four types of nitrogen bases. To form a strand of DNA, nucleotides are linked into chains, with the phosphate and sugar groups alternating.
This means that the mothers green eyes are recessive alleles and the fathers brown eyes are dominant alleles. The blue eyed puppy is blue eyed because there must have been a gene in the mothers or fathers past generation.
A zygote is immediately formed after fertilization between two gametes. This cell is eukaryotic and made up of a combination of the DNA in both gamete. Zygote contains all the hereditary information essential in the formation of a new individual.