Answer:
a. Heterozygous individuals may pass on their copy of the disease-causing allele to offspring.
Explanation:
Tay-Sachs, which is a recessive lethal disease ---- Let say the recessive lethal diseases is s
∴ it only results when an individual posses two copies of the diseases-causing allele i.e two copies of the disease will be ss.
Now, when two hetrozygous individuals crossed , it is obvious that each can pass on their copy of the disease-causing allele to the offspring.
Let show an illustration for the above statement.
Let the heterozygous individual be Ts, if Ts cross with another Ts;
we will have:
Ts × Ts
T s
T TT Ts
s Ts ss
the offspring are TT,Ts,Ts,ss
We can now see how the Heterozygous individuals pass on their copy of the disease-causing allele to the offspring (Ts).
Answer:
Transition
Explanation:
Secondary succession occurs when the existing vegetation is removed by some disturbances and soil is already present in the region to support the growth of new species. During succession, the early species are being replaced by later successional species.
In the given example, the forest has patches of early species and later species. This means that the forest is in the transition period of succession where early species were not completely replaced by the new species. Once the early species will be removed and the climax community develops, the forest has reached the final stage of succession.