Answer:
Genotype ratio = 1 X^hX : 1 XX : 1 X^hY : 1 XY
Phenotype ratio = 2 normal daughters : 1 affected son : 1 normal son
Explanation:
Given that the father of the woman has hemophilia, the father must have transferred the allele for hemophilia (let us assume "h") to her. This makes the woman carrier for the disease (genotype = X^hX). The genotype of the normal man would be "XY".
A cross between carrier woman and normal man would obtain 2 normal daughters, 1 affected son and 1 normal son.
Genotype ratio = 1 X^hX : 1 XX : 1 X^hY : 1 XY
Phenotype ratio = 2 normal daughters : 1 affected son : 1 normal son
Answer:
I think that the answer might be b and c
Answer:
Xerophyte
Explanation:
The plant will have adventitious roots and long tap root to search for water. It will also have thick bark. Or succulent stem or leaves for storing water.
Species evolve independently possibly due to geographical isolations or behavioural isolations.
Geographical isolation includes the isolation of 2 groups of the same species. Since these 2 groups live in different locations, (e.g. a volcanic eruption resulting in a barrier between one side of an ocean and another side of the ocean), they will have different selection pressures in their different environments as well (e.g. one side of the ocean may have more sunlight and thus more underwater plantations than the other side of the ocean). Natural selection will eliminate those with disadvantageous characteristics (e.g. Fishes that only eat plants and nothing else on the side of the ocean with little plantations) with unfavourable alleles, and select for those with advantageous characteristics (e.g. Fishes are able to eat plants and other organic substances as well on the side of the ocean with little plantations) with favourable alleles.
Since the 2 groups have different selection pressures, natural selection will occur in different ways, selecting for and against different types of fishes with different types of alleles. Also, because of the barrier, they are not able to mate with each other, and there are no mixing of genes from one side of the ocean and the other side. They are genetically isolated. As genetic drift occurs over time, their gene pools become different from each other. Thus, they evolve independently.
Hope this helps! :)
