Answer;
The correct answer would be Rr.
In a monohybrid cross, the phenotype ratio of 3:1 is obtained only when both the parents are heterozygous for the trait.
In this condition, the heterozygous genotype would be Rr. The phenotype of both the parents would be round seeds (R) as the round is a dominant trait.
The cross of these parents would produce offspring with three types of genotypes RR, Rr, and rr in ratio 1:2:1.
Thus, the phenotypic ratio would come out to be 3 (round seed):1 (wrinkled seed).
The best answer for this question would be:
D. Polymerase chain reaction
<span>It is used in molecular biology in order to create small fragments of the DNA. Those copies of the DNA mimic the happenings in the cell. This chain reaction is an efficient technique to further research on crimes.</span>
Explanation:
first blank is; Mitral valve.
2nd blank is; Left Ventricle