The answer is C. We can suppose that the Grey gene is "A" and Black gene is "a". So the gene of heterozygous grey fruit fly is "Aa", and the black-bodied fruit fly is "aa". After mating, the offspring can get only "a" from balck-bodied fruit fly and has equal opportunity to get a "A" or "a" from heterozygous grey fruit fly. If the gene of offspring is "Aa", it will be grey. If "aa", it will be black. So the proportion of being black is 0.5.
Answer:
The polio strains cannot reproduce because they are weakened.
Carbon dioxide and hydrogen monoxide
Answer:
limiting factors
Explanation:
The ecological optimum represents the value of the factors within the ecological valence at which the life processes of a species take place best. The upper and lower limits of an ecological valence are its maximum and minimum. Beyond these limits, physiological processes are interrupted and death occurs.
Answer: The correct answer is option a.
Explanation:
Prezygotic isolation is a mechanism by which mating and fertilization is prevented. Thus, it prevents the formation of a zygote.
It can be achieved by various reasons such as temporal differences (difference in mating seasons), habitat isolation, behavioural differences (different mating rituals such as different dance patterns, voice calls, et cetera), mechanical isolation, et cetera.
Thus, different breeding calls prevent the species to interbreed with each which ultimately prevent the formation of zygote formation.
Hence, it is a type of prezygotic isolation.