<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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Chinese hamster ovary cell production of recombinant tissue‐type plasminogen activator (t‐PA) was increased by amplification of cotransfected dihydrofolate reeducates cDNA using stepwise adaptation to increasing methotrexate (MTX) concentrations. The highest producing clones were isolated at 5 μM MTX and yielded 26,000 U/106 cells/day t‐PA (43 μg/106 cells/day). Above 25 μM MTX, cell specific t‐PA production rates became increasingly variable and the cDNA copynumbers decreased. No apparent correlation between the cell specific t‐PA production rate and the growth rate was observed upon sub cloning of the amplified cells. When MTX selection was removed, the t‐PA production rate decreased up to tenfold within 40 days; this was accompanied by an up to 60% drop in cDNA copynumber. Subclones isolated after 108 days of culture in the absence of MTX were, on average, sixfold more stable than their parental cells. In culture without MTX, the maximum stable t‐PA production rate obtained (over 250 days) was 7000 ± 750 U/106cells/day (∼12 μg/106 cells/day), approximately threefold lower than the maximum unstable levels of production reached under selective pressure. Taken together, these results define a wide range of the highest t‐PA expression rates obtained under MTX selection, for which stable expression without selection has not been reported
Answer:
Diffusion is an example of passive transport and it requires no energy.
Explanation:
DNA Polymerase is the enzyme that joins individual nucleotides!
Carbon in air is usually 2-3% but some plants have can stay with 5%
Pls can you put this answer like Brainly answer
