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Addition to what Chris already said: Papain can be used for cells sensitive to trypsin (neurons etc) Collagenase can be used for certain cells where trypsin is ineffective (Accutase is a commercially available enzyme mix(?) which has collagenase activity) Hyaluronidase - I don't know where it is specifically preferred but it is used. Pronase and ...


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Lets make this a proper answer: There are a few possibilities to detach adherent cells without Trypsin. PBS/EDTA: Integrins and Cadherins play an important role in the adhesion and also in maintaining cell-cell contacts. These function of these proteins depends on Calcium2+ ions, so EDTA will chelate them and make them unavailable. First remove the culture ...


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This is an important topic in immunology, especially for vaccine development. MHC or HLA is a molecule expressed by some cells of the immune system which acts like a "catcher's mitt" and "presents" short snippets of protein to other immune cells. Other molecules act alongside MHC to provide co-signals which promote or suppress immune attack against the ...


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I think inf3rno's answer is very complete, so I will just be adding some notes that might help OP understanding what's happening. Say that we increase the intracellular concentration of potassium by 10 mM, a +1 valence ion which contributes to POSITIVE membrane potential. Let's say we do that, in an in vitro cell model, using a syringe with only K⁺ ...


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Lehninger Principles of Biochemistry by Nelson and Cox is quite popular and covers everything you listed in great detail except for immunology. I don't really have a recommendation for an immunology book; I think pretty well any of them will cover immunoglobulins (they're pretty integral). My university uses Kuby Immunology by Kindt et al. Molecular ...


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I think this question has more to do with kinetics / transport phenomenons than biology, but that's okay, everything is connected especially my computer to the internet. ;-) The basic idea behind transport phenomenons is that there will always be a flux of quantitative properties (e.g. charges, particle number, entropy, volume, etc...) where the qualitative ...


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The membrane of the Golgi apparatus is not continuous with the membrane of the endoplasmic reticulum - in other words these organelles are not directly connected. Vesicles containing proteins destined for the Golgi apparatus bud off from the endoplasmic reticulum and subsequently fuse with the Golgi apparatus, releasing their cargo into the lumen of the ...


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Why cells differentiate or specialize is an ephemeral question. I'll make an attempt to answer--the more specialized cells an organism has, the better equipped that organism is to function. In a given organism, differentiation after n divisions or after t time during development is due to changes that are both intrinsic (genetic) or extrinsic ...


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The localization of the protein kinase A (PKA) cannot be explicitly answered, since the localization depends on the activation state of the protein. Lets have a look at the protein itself first, as this is important for the activation. PKA consists of four subunits, two catalytic subunits and two regulatory subunits. See the image from the Wikipedia article ...


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It is present throughout the cytosol but can also be anchored to plasma membrane and mitochondria via indirect interactions. Can also be translocated to the nucleus. (See here). It is not called a receptor for cAMP (though the mechanism is homologous).


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Welcome to BioSE! As @Chris mentioned, transported atoms and molecules don't typically retain a record of their past history, so just by looking at a molecule in the cell you can't in general tell how it arrived in the cell (an exception might be proteins that have some chemical modification on them that allows them to be imported via a specific mechanism, ...


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There are multicellular organism which do not actively eat other organisms, however, there are no organisms period who do not kill other organisms. Trees, and other vertical plants, evolved in the first place in competition for sunlight. For plants, being in the shade is like smother or starving a human since they literally use sunlight to create and ...


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Patch clamping Or Ultracentrifugation to get soluble fractions. If you get enough of it and u have validated its purity you could runs conductivity probe into your fraction


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Yes, plants! Plants are autotrophs. While Animals and fungi are heterotrophs. Have a look to the wikipedia articles. In short, autotrophs organisms are organisms that synthesize their own compounds from inorganic compounds. Heterotrophs organisms are organisms that synthesize their own compounds from organic compounds. Therefore, any multicellular plants ...


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It might be helpful to think about where elements in general come from. Here is a plot of relative elemental abundance. Note that the Y axis is logarithmic, so H and He are much much much more common than anything else. You'll notice that Li, Be, and B are rare, and C, N, and O are fairly common, and are the main components in biological chemistry. Fe is ...


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During ripening, pectinases are produced which break down pectin and render it soluble. Color change is also associated with fruit ripening. Hence the correlation.


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Clones are genetically identical daughter cells from one parent cell. So when you start you culture from one cell, all new cells are clones of this cell. The first three cells (red, green and blue) undergo clonal expansion. If you multiply cells in cell culture you usually start with thousands of cells, as this can be seen in the second part of the ...


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PSI-BLAST is an iterative algorithm. Each cycle it uses a model (the position-specific scoring matrix, or PSSM) to search for sequences matching the model, next updates the model with the sequences found, and then runs the search again with the updated model. That P-value controls which of the sequences found in each iteration should be included in the new ...


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Unless you are inside a star or a fusion reactor- Matter is neither created nor destroyed. However, fission of unstable isotopes is fairly common on earth's surface. You may accumulate one of such isotopes but usually the ones that are generally absorbed in our bodies such as C-14 have very long decay times (more than your lifetime). So for all practical ...


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B. Higher surface to volume ratio allows better interface with environment. C. To increase surface area the cell can form processes such as microvilli.


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Long story short: Absolutely. Short story long: While your intuition that growing a lot of cells can increase the risk of damage that might cause cancer is spot on, your specifics are a little off. It's not the telomeres themselves that are the problem, but broad spectrum DNA damage and transcriptional changes. The condition of the telomeres doesn't ...


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In a normal cell, during each replication the telomere is shortened slightly due to the end replication problem, as you probably know. As mutations occur and a normal cell begins to exhibit cancerous characteristics, it needs a way to stop the self-destruction which happens when the telomeres become too short. In fact it is the cancer cells themselves which ...


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Disclaimer: This is my understanding of the egg anatomy as a general biologist. There is most certainly better references and sources out there to explain this (please add better references if you know of any). If I understand you correctly, your question is why we do not see cell organelles in a cracked or boiled egg. If so, your question seems to stem ...


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During exercise muscles are put under stress which eventually causes micro tears in the muscle fibres. These micro tears put pressure on the nerve endings which causes the pain. The body will then repair the tears during rest and recovery using proteins and sufficient fuel. The muscle will then become slightly bigger and stronger. Energy systems used to ...


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The short answer is yes, there are single-celled organisms that can reproduce without another "partner". Probably the most famous example is that of bacteria. What you're talking about is known as asexual reproduction. In bacteria, the process is known as binary fission, where one bacterium (known as the parent cell) divides into two organisms (known as ...



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