Answer:
Option (B).
Explanation:
Neurons or nerve cell are the basic structural and functional unit of the nervous system. Fibers are the thread like long projection of the nerve cells.
Neurons are classified into three fibers- Group A fibers, B fibers and C fibers. The group C fibers cannot capable of doing the saltatory conduction of the nerve impulse because they are unmyelinated.
Thus, the correct answer is option (B).
The mechanisms of reproductive isolation prevent the reproduction of two individuals from different species. The prezygotic mechanisms disrupt the stages of reproduction before the forming of the zygote or prevent the mating at the start, and the postzygotic mechanisms affect the stages of reproduction after the forming of the zygote.
So, the first and the third example (the urchins and the grasshoppers) show the prezygotic mechanism, as the two individuals are not able to mate or form a zygote.
The second and the fourth example ( zonkey and the death of a zygote) show the working of the postzygotic mechanisms, as the zygote is formed, but it seems to be inviable, and the zonkeys are sterile, preventing the individual to reproduce.
While stopping to get gas in The Valley of Ashes, Nick notices the eyes of whom staring down at them? (hint: there are 2 pairs of eyes watching)
In my opinion I think it is.
The answer is B because it makes the most logical sense and the rest of the answered are obviously incorrect, it’s screaming “I’m wrong!!!”
