One of the major elements of natural selection is that all species have genetic variation. Natural selection is a process when organisms adapt better to their environment. It is an essential key in evolution. There is a change in phenotype of a population over time.
Answer:
Explanation:
Mendel's law of independent assortment state that two different genes assort independently in gamete formation.
To reach this conclusion, one has to do a dihybrid cross. This means that two genes responsible for different traits need to be analyzed at the same time.
1) Starting with a <u>parental generation of a cross between two pure lines</u> (homozygous for both genes) <u>with different traits</u>, a plant with yellow and round seeds (YYRR) and another with green and wrinkled seeds (yyrr). <u>The F1 will be phenotypically homogeneous (</u>yellow and round)<u>, and genotypically heterozygous (</u><u>YyRr</u><u>)</u>.
2) If the individuals from the F1 are crossed with one another, we have to do a Punnett Square to determine the phenotypic ratio of the F2.
- If the genes assort independently, the F1 individuals will produce their different gametes with the same probability. Each possible gamete will appear in a 1/4 proportion: YR, Yr, yR, yr.
- The 9:3:3:1 ratio is a result of analyzing the possible phenotypes that result from the dihybrid cross.
See the attached image for an illustration of the crosses in each generation and the Punnett Square.
I think the answer is A hope this helps
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