Explanation:
External plant structures such as leaves, stems, roots, flowers, fruits and seeds
Answer:
"...for many of our white brothers, as evidenced by their presence here today, have come to realize that their destiny is tied up with our destiny."
(A)
Answer:
Thymine in DNA occurs as the result of thymidylate synthase creating deoxythymidine monophosphate (dTMP), which then undergoes phosphorylation to deoxythymidine diphosphate (dTDP), then to Deoxythymidine triphosphate (dTTP), and incorporated into DNA by the DNA polymerase (DNA pol). Thymine in tRNA arises post-transcriptionally, by S-adenosylmethionine-dependent methylation of a uridine 5'-monophosphate (UMP) residue in RNA.
Explanation:
Thymidylate synthase is an enzyme involved in <em>de novo</em> DNA synthesis. This enzyme (thymidylate synthase) catalyzes the transfer of the one-carbon group from 5,10-methylene-tetrahydrofolate (5,10-CH2-THF) to deoxyuridine monophosphate (dUMP) and subsequent methylation to produce deoxythymidine monophosphate (dTMP), which is then phosphorylated to deoxythymidine triphosphate (dTTP) by kinases and incorporated into DNA. On the other hand, specific tRNA methylases catalyze the methylation of transference RNA (tRNA) by using S-adenosylmethionine as a methyl donor. Since tRNA methylation is a post-transcriptional modification, this chemical reaction is considered an epitranscriptomic modification on the RNA molecule.
In eurkaryotes, the wrapping of DNA around nucleosome introduces negative supercoiling because negative super coil knots have high twisting stress and are less tightly packed.The combine loop of protein [histone] and chromosome is called nucleosome.
Answer:
A genetic drift is defines as the change in the allele frequency of an existing population. It arises as a result of random variation in a population. The rate of genetic drift would be greatest in a small population that are geographically isolated from the parent population. A change in the allele frequency of a population as a result of chance rather than the natural selection.
