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2

Telomeres are at the end of the chromosomes and get shorter with every cell division, since the lagging strand is missing a start point for the DNA polymerase. This limits the number of cell divisions to 40 to 60 before the cells go into senescence and stop dividing (they are not dying at this point). This phenomenon is called the "Hayflick limit". Cell ...


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In some types of cancer cells, an enzyme called telomerase can actually rebuild the telomeres, making a cell appear "younger" than it actually is and preventing it from senescing (reaches a point where it stops dividing). Telomerase, a eukaryotic ribonucleoprotein (RNP) complex, helps to stabilize telomere length in human stem cells, reproductive cells ...


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The question is relatively broad and one should take into account that the brain not only consists of neurons, but also glial cells (supportive cells) and pre-mitotic neuronal stem cells. Furthermore, as critical fellow-scientists have indicated, developmental stage is very important, as the developing embryonic brain is very different from the adult brain. ...


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For assaying effect of alcohol on cell growth:     Prokaryotic Cells Take ~5ml medium (LB for E.coli) in test-tubes/plastic tubes and add appropriate concentration of alcohol(s) in these. Inoculate 1% bacteria from a starter culture (OD~0.6) After different time intervals or a fixed time point take some culture, dilute and spread ...


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I am not sure about what they used in 1958 (perhaps Sorvall). However you may look at recent papers for ECM protein isolation (if that was your objective). Have a look at this article. From materials and methods: ECM protein isolation. Fibroblasts or A431 cells were removed from the surface of the culture plate with 2 mM EDTA in PBS for 3–5 min ...


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Based on T Abraham's answer, a hemocytometer would work. However, a hemocytometer requires a microscope, but if you are in a cell lab, you probably have access to a microscope. I would recommend using mammalian cells instead of bacteria, they're larger and easier to see, and more relevant to human health. If you're interested in liver toxicity in particular, ...


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Great idea! It seems that this research has been done before and your hypothesis is correct, but testing a wide variety of alcohols and testing your hypothesis for each one of them would be a great project. Now, to do this, I would expect you would need to check the growth of the cells after certain periods of time. How would you do this? Well, the best ...


1

This is somewhat tricky, so one has to pay close attention to the definitions involved. First of all, some definitions (http://en.wikipedia.org/wiki/Chromatin): Simple and concise definition: Chromatin is a macromolecular complex of a DNA macromolecule and protein macromolecules (and RNA). The proteins package and arrange the DNA and control its ...


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You can use some antibiotics or germicide or alcohol...they prevent the formation by interfering with the attachment or adhesion and expansion of immature biofilms..


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There are various mechanisms through which membrane proteins can remain localized in the membrane. See the below figure from MBOTC (book): ...


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The usual 'heat resistant' bacteria or thermophiles are free living organisms with specific niche and are not pathogenic. Most pathogens are mesophiles and that is why they are grow in the body temperature. Spores are thermotolerant but spores are dormant and are not actively growing microbes. Having said that, different mesophiles can have different ...


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This specific experiment has not been done. Fusing cells is difficult and it also leads to polyploidy. Cells are immortalized by overexpressing oncogenes (or viral replication genes); for example HEK293 cell line was established by transforming embryonic kidney cells with adenovirus. Now transforming a neuron would immortalize it but would also make it ...


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There is a single basal body per cilium. During cell division the centrosome has two centrioles, however, during the differentiation of citiated cells, there is an amplification of basal bodies that nucleate from the centrioles. In multiciliated cells the basal bodies arise from two pathways- 1. de-novo / deuterosomal / acentriolar pathway and 2. ...


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The book "Basic Histology" by Junqueira and Carneiro acknowledge the problem in histologic fixation of ground substance. They recommend freeze drying in liquid nitrogen and then removing water by high vacuum at a temperature of -30 celcius, which will cause sublimation (ice-->vapor). Then fixing the sample with a nonpolar solvent. Afterwards you can use ...


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Different components of the ECM can be stained differently but since you asked about hyaluronic acid (HA) I'll limit my answer to its staining. See this paper. They use Hyaluran Binding Protein (HABP) as a specific probe for HA. Because HA has a very simple, conserved composition and is ubiquitously expressed in all animals that have a developed ...


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From this paper: We chose to test for Cas9-driven targeted mutagenesis on the endogenous Trp53 gene in mouse embryonic fibroblasts (MEFs), a cell line in which the biology of p53 has been thoroughly characterized and where the gene is structurally intact. Furthermore: Seventy-two hours post-transduction, cells were cultured in the presence ...


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Cells take up external material in the process pf phagocytosis. This involves creating a vesicle from plasma membrane that will contain the external material. The vesicle enters the cytoplasm where it is called (early) endosome. The cellular membrane components of this endosome are recycled and gave back to the plasma membrane. The endosome pH decreases and ...


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Try thinking about places that are not very often cleaned and disinfected such as the toilet. Not only that, but the bottoms of shower curtains and in drains. Plaque on teeth is a biofilm, catheters, in/on wounds.



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