<span>The correct answer is
(a) True, it is of paramount importance to use primary, secondary, and tertiary
sources in research. Researching includes using primary sources as they contain
original materials on which research is based, but also using second sources as
interpretations and evaluations as other researcher’s point of view. That also
apply for tertiary sources that
represent distillated and collected information of primary and secondary
sources.</span>
Probably B) strenuous exercise. If not B then it's probably A. I don't know for sure though
<span>Since alkylating agents work to prevent the cell from replicating its genetic material, the cell would most likely stop at the interphase checkpoint, which is the phase before mitosis (which consists of prophase, metaphase, anaphase, and telophase). During interphase, the cell replicates its genetic material (DNA), but this would be prohibited by alkylating agents.</span>
Answer:
Generally, oil immersions are used when one has to witness the cells from the inside and is mostly seen at 100X objective. The oil immersions are used to cope with the RI or the refractive index, as when light goes from a substance of one RI to the substance of another RI the light gets scattered.
One is not able to see the cells when the slide is placed upside down, however, when the slide was turned over then everything becomes clear. As basically when we look through the microscope then initially the top thread comes into focus succeeded by the middle and eventually the bottom one.
However, when one put the slide upside down then at that time the slide function as the first thread and the cells function as the second thread. As the slide is formed of dense and thick substance it is tough to focus the second thread or the cells via it. This is the reason that one is not able to witness anything when the slide is kept in this position.
