Answer:
C. Beak size is an inherited trait in the finch population under study.
D. Birds that could eat larger, tougher seeds survived and reproduced during the drought.
E. Beak size varies among the birds in the finch population under study.
Explanation:
The presence of genetic variations among the individuals of a population is required for natural selection to be operative. Natural selection targets the beneficial genetic variations present in the population. Natural selection refers to the differential reproductive and survival success of organisms of a population due to some beneficial genetic traits. These organisms with beneficial genetic traits are able to survive and leave more progeny under prevailing conditions.
If the natural selection has occurred in the ground finch population for the beak size, the beak size should be a genetic trait since natural selection works on genetic traits only. The finch population should have variations with respect to the beak size. The finches having the larger beak size that enabled them to feed on larger, tougher seeds should have higher survival and reproductive fitness during the drought.
Under these conditions, natural selection would favor the finches with larger beak size and would eventually result in an increase in the average beak size of the future generations.
PDK1 (pyruvate dehydrogenase kinase 1) is an enzyme which inactivates the pyruvate dehydrogenase by phosphorylating it using an ATP molecule<span>.
</span><span>PDK1 (phosphoinositide-dependent protein kinase-1) acts by catalyzing the phosphorylation of Thr-229 (threonine at position 229 in pyruvate dehydrogenase).
This phosphorylation is </span><span>synergistic</span> with the phosphorylation of C-terminal Thr-389, but this one is not done by the PDK1.
<span>Meiosis in simple terms is the process by which gametes (sperm and egg) fuse together to produce a fertilised egg. Haploid is a word that refers to how many chromosomes a certain cell has. In this case the gametes have a haploid number of chromosomes, which is half the number a normal cell has. A normal cell has a diploid number of chromosomes. So in meiosis the two gametes come together with their hapoid number of chromosomes each to create an egg that has a diploid (standard) number of chromosomes.</span>