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The group tries to predict possible epitope sequences for the generation of antibodies. This includes also non-linear epitopes where not all amino acids of the epitope are line up behind each other, but come in close contact due to a 3D-structure. To train their algorithm, they use data, where the boundaries of the epitopes and the non-epitopes are known and ...


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The inner membrane is that of the engulfed bacteria. The bacterium would have been phagocytosed by a larger cell. Hopefully you can see in this image the smaller cell being engulfed in the membrane of the larger cell: [ source ]


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Tl;dr answer, tumors are abnormal growth (or swelling, thanks to Malic for pointing out) of any kind. The kinds of tumors are benign and malignant. Benign tumors are usually slow growing and harmless. Example would be a lipoma. Malignant tumors are otherwise called cancers. They generally have a bad prognosis. Very few cancers are curable. Swelling ...


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Without answering the problem for you, because you have not shown work yet to try to figure out which is which, let me tell you that you have three options. Skeletal Muscle- striated, peripherally located nuclei, same thickness along length, non-branching Cardiac Muscle- striated, few centrally located nuclei, branches and anastamosis Smooth Muscle- ...


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The answer given above by Chris is correct, but does leave out one relatively recently discovered method of cell death, somewhere between the two responses of apoptosis and necrosis. It's called pyroptosis. It's a form of programmed cell death (in immune cells, e.g. macrophages), so it is similar to apoptosis. However, instead of a neat and tidy ...


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There is nothing intrinsic to DNA methylation itself that requires it to repress transcription. Simply, it affects sequence recognition by proteins. CpG methylation can prevent transcription factor binding and/or recruit proteins that inhibit transcription, either competitively or through chromatin condensation. This is why it's generally associated with ...


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Tumor cells can have very unstable genomes, as much of the error repair machinery is damaged or missing. Since the cells are rapidly dividing and the DNA gets duplicated each time a cell splits, more and more mutations accumulate as the tumor grows and metastasizes. Just like in evolution as a whole, mutations that are either neutral or help the cell survive ...


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A tumour is simply a space-occupying lesion (something that should not be there, that is; a "lump") caused by abnormal cell replication. (In medicine, the word "tumour" literally means "swelling", and can sometimes refer to that instead, but that's a different story). Cancer is a disease in which cell replication is totally out of control. What causes ...


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It's not a single grass cell, but this does indeed appear to be a micrograph of a leaf of grass—so it actually contains numerous cells. Here's another image I was able to find with a much more clear description of exactly what you're seeing: Marram grass leaf. Light micrograph of a cross section through a closed (unravelled) leaf of Marram ...


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There is actually no preference for apoptosis or necrosis in cells of the human body - both types can occur in all cells and they have different triggers. The main differences can be seen in this figure (from here): Apoptosis (also called programmed cell death) has three different triggers (intrinsic, extrinsic and Perforin/Granzyme pathways), see the ...


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Necrosis can be described as accidental cell death or damage, triggered possibly from external environmental factors such as exposure to radiation, toxins, excessive heat and etc...whereas, Apoptosis is a programmed form of a cell death mechanism. This process may be used to recycle unwanted cells in the body. Therefore, the particular stimulus that the cell ...


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One technique that I like is Immunofluorescence. You get images like this: The staining are caused by applying antibodies with an flourescent probe. The antibody 'sticks' to certain parts of the cell, & the probe produces the light patterns you see.


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Beyond the conventional methods listed by Chris Stronks, Berkley Labs have far advanced the state of the art in probing the internal structures of cells using x-ray tomography. See: http://ncxt.lbl.gov/ . The images obtained are absolutely incredible and allow researchers to probe the cell layer by layer and visually contrast specific organelles for study ...


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Techniques to look at whole cells are: Light microscopy (cells, large organelles), electron microscopy (detailed analysis of subcellular structures and even proteins) and confocal fluorescence miscroscopy (look at particular cellular planes, reconstruct 3D images). And of course you can analyze the insides by Biochemistry by breaking the cell membranes and ...


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The answer is, in part, it depends. Let's think of the PI3K/AKT pathway. Akt actively phosphorylates BAD which abrogates the Bax/Bak apoptosis pathway. RTK's at the plasma membrane activate this pathway when bound with survival factors. In the absence of survival factors, Akt would become dephosphorylated and you'd have a net movement toward apoptosis. In a ...


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One event that comes to mind is the use of radiation on cancer patients. Radiation is an external event that can trigger apoptosis in humans 1. When cancer patients receive radiation, the treatment is localized. The brain isn't telling the cells to die it is the radiation effects on the cell. Ionizing radiation can also induce apoptosis via the ...


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Short Answer Death! Longer Explanation In terms of the cellular and molecular level, many of the relatively weak interactions holding a person together are disrupted by cold temperatures. As a cell freezes, most of its proteins and lipid membrane content will denature and "fall apart", the same as if you boiled it. As with many things in biology, the ...


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This answer also involves some speculations as the question is about a good theoretical framework for a science fiction. You can find in this post about how sperm can be used to produce embryonic stem cells. It would still require an oocyte for doing that. The question now is- Can you produce oocytes from a male? You may fuse two X bearing haploid ...


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Theoretically this should be possible as men carry both sex chromosomes. You would have to find a way to make haploid cells and then have them form a diploid cell with two x chromosomes. Your population would go through a genetic bottleneck which would soon cause a lot of other genetic problems as there is not enough variety. But besides this rather ...


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A woman (assuming no mosaicism) has two X chromosomes in the nuclei of her cells (except for oocytes). A man, in every cell with a nucleus (except for spermatocytes), has only one, pluripotent or not. The only way he could make a female would be to either manipulate cells by duplicating the X chromosome (very difficult to do) or remove/inactivate the Y ...


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In the case of myofibrils this is the case because of the syncytial nature of that given structure. It means that in developing muscle tissue after a certain stage the cell divisions become somewhat different in that the final step, being separation of the daughter cells via invagination of cell membranes, does not happen. The nuclei though keep dividing ...


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epitope in immunomic microarray DNA microarrays measure one response value for each gene per sample; that is, mRNA concentration produced by the gene but a single epitope can generate different response values corresponding to different epitopes in peptide–MHC chips. The excerpt looks grammatically incorrect and is therefore confusing. I guess ...


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First, I must clarify that a nerve is not the same as a neuron. A nerve is a collection of axons (with each axon a part of an individual neuron) in the peripheral nervous system. Thus, when you mention “single long axon such as the sciatic nerve”, this is technically an incorrect phrase as the sciatic nerve is a collection of many long axons. If one of these ...


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As with so many things, it depends. Also, I'm a bit unclear when you say antibody-receptor interaction, do you mean that you have an antibody that's specific for a receptor, or that you're studying Fc receptors binding to antibodies? (for the following, I assume the former) For most cell types and most cell surface molecules, simple antibody binding isn't ...


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It's a complicated answer. More than 200 cell types, each type of cell inherits a unique expression of receptors, internal and external. Diffusion of signals through the plasma membrane and/or nuclear compartment may act directly as cofactors, activators, etc. The specific sequestration, and pattern of expression of external receptors also influence what ...


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They are not individual cells. In fact, the "juice sacs" (as they are known) are actually specialized, multicellular hairs: Juice sacs originate as multicellular hairs in which the interior of the enlarged distal part breaks down and fills with liquid. The juice sacs constitute the fleshy, edible pulp of an orange and are the source of the sweet juice. ...


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Tumors can be benign (they don't bother you at all eg: a mole which does not change) and malignant (also called cancer). The difference is based on:- Degree of differentiation - How much the tumor cells resemble the normal cells Rate of growth - In general (over generalised) benign tumors are slow growing while malignant tumors are fast growing Spread to ...


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Here's an overview of both the Light and Dark cycles of photosynthesis, which looked particularly useful to me as it shows that the energy-carriers ATP and NADPH2 generated through solar energy are used in the dark cycle to generate sugars. . Here is another one that shows more details on the precursors involved in the Calvin cycle: As commented by ...



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