No, price doesn’t increase on demand.
Answer:
Because natural selection selects for it. Thus it persists.
Explanation:
You have to understand heterozygote advantage. Basically, it's where heterozygotes have an advantage over homozygotes. In the case of sickle cell disease, heterozygotes have an advantage, and natural selection favors whatever is advantageous. Thus, because heterozygotes each have one recessive sickle-cell allele, as natural selection favors the heterozygotes, the recessive sickle-cell allele persists and remains in the gene pool.
I believe the answer is <span> 9:3:3:1 ratio with 9 polka dot tails and long eyelashes, 3 polka dot tails and short eyelashes, 3 solid tails and long eyelashes and 1 short tail short eyelash! Good Luck in this biology thing your doing :)</span>