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First question: B. The net gain of ATP in Photosynthesis is 0, so it cannot be A. C & D are obviously not true. Second question: B. D is not true, C is not true (it is actually the opposite- Chloroplasts absorb all BUT green, so only green would be bad). Like another commentator said, the level of CO2 only aids the rate to a point, at which the rise is ...


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I would say Nucleus is the odd one out. Chloroplast (which have Grana in them) and Mitochondria are involved in the process of creating/breaking down energy, whereas the Nucleus is, so to speak, the blue-prints of the cell. To summarize: Chloroplast is involved in Photosynthesis to create energy Grana are in the Chloroplast, which is involved in ...


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The cell wall is an organelle, but the cytoplasm is not. My guess is that the wall regulates movement (ie, active function), whereas cytoplasm is just a fluid in which the other cells are surrounded (ie, passive). http://www.edu.pe.ca/gray/class_pages/rcfleming/cells/notes.htm Note that the terms active and passive are not being used in any scientific ...


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Cells absolutely can be considered as diffusing objects. However, the origin of the "diffusion" can be very different than for, say, a bead in water. The reason is that the thermal motion that creates the diffusion of a micron-sized bead can be much less important for a (large) cell. For instance, the diffusion coefficient due to thermal forces of a ...


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I can't tell if you're asking about glassware or work surfaces (hoods, benches etc), but... We use regular old dawn dish soap in my lab because what's more important than the soap you use to wash you're glassware is the water you use to rinse it. We teach our undergrads the 3-rinse-rule. After soaping, every item gets 3 rinses with normal tapwater (or ...


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The only strategy close to your suggested description is based on FUCCI sensors. Fluorescent markers designed so that their presence informs of specific stages of the cell cycle, in principle without disrupting or perturbing cell progression. So, although there is not a physical clean-up of pure cell sub-populations, these can be tracked by the abundance of ...


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The protein doesn't move towards anything. It just randomly diffuses (bounces around) in the cell until it sticks to something. The particular chemical structure (the shape) of the protein and whatever it hits will determine how tightly they stick together and whether or not a chemical reaction occurs. A way to imagine this is to think of a jar filled with ...


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Your question spans two activities of T-cells that are related to each other: migration and activation. T-cells that usually stay in lymphoid organs migrate to non-lymphoid organs with different mechanisms for each T-cell subtype. When migrated to non-lymphoid organ, the T-cells move through the organ looking for infected cells. Migration As you can see in ...


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T-cell does not inspect any cell until the cell shows a piece of the "non-self" antigen on it by the MHC. The helper T-cell connects with the antigen which is on the cell's surface. The T-cell sorts the cytokines that activate the cytotoxic T-cell to divide and form a colony of cytotoxic cells. The colony of cytotoxic cells then attack the "non-self" ...


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If you mean to say why DNA is in the form of chromosomes, then obviously answer is simple: For Compression and Packaging - Around 2metre long DNA must be compressed (at an unbelievably high ratio) to let it fit in the tiny nucleus (order of micrometers)


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Recent nature neuroscience review on bipolar cells says that bipolar cells are classified into 13 (12 cone bipolar + 1 rod bipolar) different types. Depending on the polarity of their light response, bipolar cells can be grouped into ON and OFF cells. Answering your question, what are on bipolar cells used for ? ON bipolar cells predominantly depolarize ...


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Bacteria or other microorganisms cannot really grow on anhydrous (totally dry) glucose because they need water. However, they can remain there and cause contamination. Even if you haven't actually touched the glucose sample, there are many bacteria suspended in the air and they may settle down in your glucose packet. When you take the glucose out for ...


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Ribosome assembly starts in the nucleolus (of eukaryotes) and finishes in the cytoplasm. However, in the cytoplasm the Golgi apparatus is certainly not involved, and, as some cells have little rough endoplasmic reticulum, assembly does not require that. Thus, the abstract of a review by Fromont-Racine et al. in Gene (2003) vol 313 pp. 17–42 starts with the ...


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What you're asking is essentially to prove a negative ("Are there no ways an unchecked cancer can be non-lethal?"), which is unfortunately more of an exercise in imagination than anything else. The best way I can answer is by highlighting what about cancer actually kills, from which you can personally evaluate if a particular type of cancer fits and would be ...


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The following is not an answer to the original question: "Are Gram negative bacteria classified as such because of their negative membrane potential?" but to the questions later in the text. Usually the membrane potential is given for the inner cytosolic part and the extracellular space, for E. Coli it is around -120 mV; see also this article. Due to the ...


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Short answer The distinction between Gram positive (Gram+) and negative bacteria (Gram-) has absolutely nothing to do with membrane potentials; it is all about the Gram staining procedure. Background The Gram staining was named after the Danish bacteriologist Hans Christian Gram, who originally devised it in 1882 (Gram, 1884). Gram staining is a common ...


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In most cases, it's not a good idea to replace glucose with glycerol in animal cell media. Animals do possess the ability to metabolize glycerol, via a pathway starting with the enzyme glycerol kinase. However, glycerol kinase is only expressed in certain cell types, such as liver cells and kidney cells. References: ...


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‘Reversible’ and ‘Irreversible’ are standard designations in enzyme kinetics. It may be that your instructor was using the word in this sense. As already commented, irreversible inhibitors bind the enzyme in such a way that they don't dissociate from it. Either they form a covalent bond or their affinity for the binding site is extremely high. Reversible ...


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At room temperature, Nail bed . It's not about survival. Those cells have a low growth rate. Other cells in bones may 'live' longer but harvesting bone marrow in decaying animals has not been done. If you freeze cells, they can last decades.



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