Answer:
B. 25%
Explanation:
Assuming the trait for teeth size is represented by the allele A. large teeth size is dominant and will be represented by A while small teeth size will be represented by a.
Assuming that the population of 1,000 [piranhas are all heterozygotes and they crossbreed with one another:
Aa x Aa = AA, Aa, Aa and aa
The ration of piranhas with large teeth to that of the small teeth is 3:1 or 75:25.
Hence, about 25% of the next generation of the population is ecpected to have small teeth.
The correct option is B.
A have the MC1R gene and melanin deference
Alcohol fermentation occurs in the cytosol of yeast cells.
The mucus blocks the path from which the air/smells enters in through and causes your smell to be dodgy.
The answer is Rr and rr.
We know:
r - recessive allele
R - dominant allele
RR - dominant homozygote with red eyes
Rr - heterozygote with red eyes (since one dominant allele R can mask recessive allele r)
rr - recessive homozygote with sepia eyes
Heterozygote Rr can give to the offspring either dominant allele R or recessive allele r. Recessive homozygote rr can give to the offspring only recessive allele r (take a look at the uploaded image of Punnett square).
After crossing the parents:
Parents: Rr x rr
Offspring: Rr rr Rr rr
So:
2 out of 4 offspring will be with heterozygous with red eyes Rr: 2/4 = 0.5 = 50%
2 out of 4 offspring will be with homozygous with sepia eyes rr: 2/4 = 0.5 = 50%