Answer:
1. Iterative homology: e.g. antenna and leg of fiddler crab
2. Ontogenetic homology: e.g. radular teeth of veliger, feathers of chicken and hen
3. Di-polymorphic homology: e.g. white and brown feathers of hen races, chelae of male and female of fiddler crabs
4. Supraspecific: e.g. chelae of fiddler crab, chelae of lobster, feathers of hen and pheasant
Explanation:
The father determines if its male or female. So the father is the carrier and the allele is on the Y chromosome.
I'm a little confused by this question. Hypertonic just means that something has more of something than another thing. For example, if you place a cell in a solution, and 2% of the cell is made out of something while the solution is made out of 40% of the same thing, the solution would be hypertonic to the cell. Sorry if that explanation doesn't make sense, I tried my best lol.
Although I'd assume the answer is passive transport as anything that is hypertonic to something else will diffuse down its gradient in an attempt to reach a balance.
Phenotypes are the physical characteristics that result from the genotype, which is the genetic makeup of the organism. In this case, either straight hairline or Widow's peak will be the phenotype, as they are the physical characteristics being discussed.
The questions states that a Widow's peak is dominant over straight hairline. So we are going to assume that the Widow's peak allele is W (dominant), and the straight hairline allele is w (recessive).
A dominant allele will mask the presence of a recessive allele unless both of the alleles are both recessive (both ww).
So for the WW genotype, we are going to see the dominant phenotype: Widow's peak.
For the Ww genotype, we are also going to see the dominant phenotype since the dominant allele is going to mask the presence of the recessive allele, so we are going to see: Widow's peak.
Lastly, for the ww genotype, we are going to now see the recessive phenotype, since both alleles are recessive: straight hairline. Note that their are two of these type of offspring as stated in the question.