A gene is a small segment of DNA that contains the information required in order to build a protein!
Seymour Benzer used phage T4 mutants, Experimental
evidence that a gene is a linear sequence of nucleotide pairs. Some regions of
chromosomes have "hot spots" for mutations. Benzer's experimental
approach to fine structure mapping of the rII locus. Generated 1612 spontaneous point mutations
and several deletions in rII locus identified two complementation groups, rIIA
and rIIB. Mapped locations of deletions
relative to each other using recombination.
Mapped locations of point mutations relative to the deletions. Tested
for recombination between all point mutations within the same complementation
group.
When people say words hurt is bc your feelings com from your brain and when you feel hurt or sad your brain makes the feeling physical. Like if you are depressed then your brain makes you sleep a lot so that you don't have to feel that pain during the day. Also, people can die from a broken hart bc it isn't your physical hart that is feeling everything it is actually your brain so it makes it self sabotage.
Traits controlled by genes can only be acted upon natural selection because they have to helpful to the survival of that organism.
Trisomy=3 chromosomes; 1 more than the required pair (2)
21=the type of chromosome
So, here we can eliminate A and B.
Now we have C and D.
I know that when sperm cell(s) simultaneously fertilize [an] egg, a class of identical twins will form. Therefore, we can eliminate D, leaving us with merely C. Henceforth, C is your final answer.