The dichotomous key is used as a classifying tool for items in the natural world, (trees, wildflowers, mammals, reptiles, rocks...). At each step of the classification process,<span> the user is given two choices and each choice leads to another question until the item is identified.</span>
<span>A dichotomous key starts with specific information and leads to general information.
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<span>The similarities between an onion and whitefish cells exist in the cell division process. Normally the basic process of mitosis cell division is similar for plant cells and animal cells, but there are fundamental differences that mark the mitosis of plant and animal cells. Basic similarities of onion cell and that of whitefish embryo cell is that in the four phase of mitosis namely, Prophase, Metaphase, Anaphase and Telophase occurs in similar way. In Prophase for both cells the chromatin condensed and in metaphase the chromatin aligns in the center of cell and kinetochores of chromosomes attached with the microtubules of spindle from opposite poles. In Anaphase stage, the chromatids from the metaphase plate are separated and shifted to opposite poles.. Finally at Telophase, the cell divides via cytokinesis. The fundamental difference between Onion cells and Whitefish cells can be found in the process of cytokinesis.
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<span>The answer is progesterone. This hormone is important in maintaining pregnancy. It is produced by the ovaries (</span>corpus luteum<span>) in the early stages of pregnancy before the placenta takes over. Progesterone ensures the walls of the uterine remain thickened hence prepare for implantation</span>
Assuming Complete Dominance, Only 1 copy of a Dominant allele of a specific trait is needed to exhibit that trait.