Answer: If the F2 occurs in the ratio 9 blue:3 pink:4 white, one gene pair (i.e 2 genes) control the flower color phenotype.
Explanation: This principle is called INCOMPLETE DOMINANCE where one gene (dominant) won't completely override the other (recessive).
Let assume B represents the dominant gene and b represents the reccesive gene. Let also assume that Blue color is dominant over white color. We can assign the genotype as follows;
Homozygous dominant genes BB will produce Blue color
Homozygous recessive genes bb will produce white color
Heterozygous genes Bb will produce pink color.
Therefore, a pair of gene ( 2 genes) will determine the flower color phenotype.
I believe the answer is A because this is the two loop system because the air you take in from your lungs automatically is polluted. In the two loop system, the carbon dioxide is taken out out of the oxygen and is pumped back to the heart to be taken out of the body. The oxygenated blood is pumped into places it is needed.
D they are unique and they may be adapting
Adenine which is a purine base, always pairs with the pyrimidine Thymine in DNA and Uracil(also a pyrimidine) in RNA. The bond which is present between the two bases is a double hydrogen bond.
Guanine which is also a purine base, always pairs with the pyrimidine Cytosine, in the case of both, DNA and RNA. The bond which is present between the two bases is a triple hydrogen bond and hence, is stronger than the A-G double bond.
The answer is A, just took the test on edge
