Answer:
paleoclimatologists use different sources of information from fossils in order to record past climate and environmental conditions (for example, tree rings or skeletons of coral reefs)
Explanation:
Paleoclimatology is the discipline that studies ancient climate and environmental conditions. Paleoclimatologists are researchers that analyze different sources of evidence to obtain accurate records of past climate conditions. In this regard, the fossil record has proven to be a useful tool to obtain such information. For example, the rings of fossilized trees are usually wider during warm and wet years, while these rings become thinner during cold and dry years. Moreover, geochemical records from the skeletons of fossil corals (composed of calcium carbonate) are good indicators of past climate conditions because coral growth is sensitive to small fluctuations in water temperature. Paleoclimatologists also use non-biological climate indicators (e.g., sediments and ice sheets) to reconstruct past climate and environmental conditions.
Mitosis begins with prophase, during which chromosomes recruit condensin and begin to undergo a condensation process that will continue until metaphase. In most species, cohesin is largely removed from the arms of the sister chromatids during prophase, allowing the individual sister chromatids to be resolved.
Prometaphase begins with the abrupt fragmentation of the nuclear envelope into many small vesicles that will eventually be divided between the future daughter cells. The breakdown of the nuclear membrane is an essential step for spindle assembly.
Next, chromosomes assume their most compacted state during metaphase, when the centromeres of all the cell's chromosomes line up at the equator of the spindle. Metaphase is particularly useful in cytogenetics, because chromosomes can be most easily visualized at this stage. Furthermore, cells can be experimentally arrested at metaphase with mitotic poisons such as colchicine.
The progression of cells from metaphase into anaphase is marked by the abrupt separation of sister chromatids. A major reason for chromatid separation is the precipitous degradation of the cohesin molecules joining the sister chromatids by the protease separase.
Mitosis ends with telophase, or the stage at which the chromosomes reach the poles. The nuclear membrane then reforms, and the chromosomes begin to decondense into their interphase conformations. Telophase is followed by cytokinesis, or the division of the cytoplasm into two daughter cells. The daughter cells that result from this process have identical genetic compositions.
Answer:
it is the measure of the clarity of the image.the minimum distance between two points can be separated and still be distinguished as two points is resolving power.it is important because it helps to see small molecules that can't be seen with naked eye
Explanation:
