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2

A PlOS One study notes drinking coffee (aka moderate caffeine intake) doesn't necessarily lead to hydration. They note coffee has hydrating qualities akin to water. Further empirical studies found no substantial fluid loss in caffeinated beverages. EDIT: Make note we're talking normal doses and moderate intake, though source 2 goes into diminishing effect ...


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These drinks contain minor diuretics. Caffeine is the diuretic found in tea and coffee. Alcohol is the diuretic in beer. Diuretic substances increase the amount of urine produced i.e causes dehydration.


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Alberts et al, Molecular Biology of the Cell, say that eukaryotic ribosomes add about 2 amino acids per second, and bacterial about 20 per second (5th edition, p 275). These should be taken only as ballpark estimates: the rate certainly will vary from species to species, from cell to cell, from protein to protein. Some cells (reticulocytes, for instance) are ...


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Glycogen storage limitation is due to these additional facts also: Glycogen is a hydrophilic molecule. This means an increase in glycogen concentration will cause a proportionate increase cell weight due to water accumulation. As cells can contain only limited volume the amount of glycogen stores are limited. Lipids are hydrophobic hence can be ...


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In this presentation from stanford.edu, it's stated that the number of granules is directly dependent on the number of glycogenin molecules available, and the size of the granule is directly dependent on the need for physical association b/t the glycogen synthase, and glycogenin.


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The simplest route to your answer would be through the kcal consumed/expended equation. 1kg (2.2lbs) of fat has ~7700 kcal of energy. The average person requires roughly 2000kcal per day if they perform mild physical labor throughout their day - 25.9% of the total energy available in 1kg of fat. So you could say that if a person did not eat for a day they ...


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A ribosome is where amino acids are linked together by peptide bonds. True. A virus is NOT considered prokaryotic because it does not have a membrane. Some have capsules or envelopes, the latter of which are composed of the host cell's membrane. A virus would not be considered a prokaryote because it is not strictly alive -- prokaryotes do not ...


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Cytosol is the fluid portion of cytoplasm. All organelles are suspended in the cytosol but they do not form a part of cytosol. See here for a detailed explanation. As Chris Stronks mentioned all cells have cytosol, but the red blood cells specifically do not have any organelles. The cytoplasm of RBC has only cytosol in which hemoglobin is suspended. So ...


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1-6: OK; prokaryotes. Cytosol is the portion of cytoplasm which is devoid of any organelles, i.e., cytoplasm = cytosol + organelles. As prokaryotes don't have any organelles in their cytoplasm, they have only cytosol. So the answer would be prokaryotes (their cytoplasm consist of cytosol only). For a special case in eukaryotes see Crags answer below. ...


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Unfortunately at this time, there are no known glucosepane breakers which can feasibly be used in a living organism. There is a small (very small) amount of research being done on the topic by Yale university in cooperation with the SENS foundation, but the focus is extremely early stage - nothing more than synthesis and detection of artifical glucosepane ...


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Welcome to Biology.SE. First off, .. I'm assuming insects are at an earlier evolutionary stage than humans It is not the core of your question but still I want to point to this sentence. What is an evolutionary stage? Does it really mean something to you? What is sure is that a given insect individual or a given human both have evolved for exactly the ...


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You have a point. But it I think this question might be closed as arguing semantics rather than biology. You're right, according to standard rules of nomenclature it would be called glycerol 1-phosphate. It comes back to the outdated D/L configuration nomenclature. A more thorough explanation is quoted below. When the R/S system (sequence rule) is ...


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Polar simply means the electron density is not distributed evenly across a molecule. In water this is caused by the comparatively higher electronegativity of the Oxygen (you can think of this like Oxygen wants the electrons it shares in the covalent bond a lot more than the Hydrogen does so it keeps them closer but this is an oversimplification). This ...


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Polar means there's a higher density of electron on the oxygen and a lower density of electrons on the hydrogens. This has to do with the electronegativity of the elements in question. Hydrogen is in group 1 which likes to lose it's electron and oxygen in group 16 which likes to get two electrons (in this case one from each hydrogen) in order to complete the ...


2

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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Yes. The research team, led by the Durham Centre for Crop Improvement Technology, and including experts at the University of Nottingham, Rothamsted Research and the University of Warwick, have discovered that plants have the natural ability to regulate their growth independently of Gibberellin, particularly during times of environmental stress. They ...


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Thank you for the fascinating question! It was tough to research but very worthwhile. LDL is actually not such a bad molecule. It is formed from VLDL/IDL after VLDL/IDL distribute triglycerides, phospholipids, cholesterol and cholesterol esters to peripheral cells. With less to give, LDL subsequently tries to be helpful by providing any needy peripheral ...


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This is a guess. Tryptophan is a bulky amino acid. Having a lot of if would make the protein bulky. It is anyways hydrophobic and cannot be present on protein exteriors; high tryptophan may distort hydrophobic core possibly because of its bulkiness and ability to form pi-stacking interactions. However, tryptophan is an essential amino acid and cannot be ...


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Under conditions of high CO2 (in tissues such as muscle) and hence high acidity hemoglobin binds preferentially CO2, thereby mediating CO2 removal. Under conditions of low CO2 (high pH) and high O2 (conditions met in the lungs), it preferably binds O2, thereby releasing CO2. Hence, the specific characteristics of hemoglobin allow for CO2 uptake in the body, ...


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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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8M urea is a denaturant, as @Chris mentioned. Denaturing proteins is important for molecular (aka classical) mass spectrometry. If you analyzed a non-denatured protein, you'd get information not only on the primary structure, but also on noncovalent interaction (2+°): The classical MS approach, so-called “molecular MS,” analyzes, in the gas phase of the ...


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Abiogenesis, the development of living things from non living matter, is not something we know much about, since it happened about 4 billion of years before we were around and haven't reproduced it in the lab. My guess is that it's not easy. However, the Miller-Urey experiment and others have told us something about abiogenic production of organic compounds. ...


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Abiogenisis, where imperfect micelles (spheres) of hydrophobic carbon chain formatiions leads to potentials for capturing and mixing elements and molecules forming peptides, polypeptides and protiens that can then catalyze enzymes to patterns to the micelle to a cell of sorts. Was it inside a terrestrial micelle that life formed or Did amazing spiraling ...


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There are two questions here: Why does life only generate life? Why doesn't life continue to be generated on Earth? The first one is easy. We don't only generate life. If that were true, it might be illegal to flush toilets. Life forms of some kind would occupy all the space in our atmosphere. Babies - or some living things - would rise up from our ...


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Preamble In short, fructose kinases (like Fru6P,2-kinase) and fructose phosphotases (such as Fru2,6bisP) regulate and are in turn regulated by fructose (specifically Fru6P) levels in plants. There are also several metabolites that regulate the rate at which those fructose enzymes function creating quite a complex fructose regulatory network. This ...


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Perception of saltiness is because of the sodium ion. At concentrations ≤ 100mM, sodium ions elicit a taste response pathway which is inhibited by a small molecule called amiloride. Other monovalent cations do not elicit this "amiloride-sensitive" response. At higher concentrations sodium ions elicit a non-amiloride sensitive response; other ions like K+ ...



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