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One of the most used surgical technique is Roux en-Y where the small intestine is divided approximately 40-50 cm below the lower stomach outlet and is re-arranged into a Y-configuration. The portion of intestine (jejunum) from the upper stomach is called the "Roux limb". It has a total length of 80 - 150 cm. So the Roux en-Y technique "bypasses" only the ...


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This answer doesn't add anything to the others, but is an attempt to explain using different language. "my question is why the water of cytosol doesn't dissolve the ionic part of the lipid bilayer" In a sense, it does. See my diagram below The bilayer is composed of phospholipids, classic amphiphiles with a polar head group and a nonpolar tail group. The ...


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ADDENDUM Water can disrupt the intramolecular hydrogen bonds by bonding to the donors/acceptors. However, water in many cases can also act like a bridge and stabilize the protein structures. As already pointed out by jarlemag, the hydrophobic residues can push the water out of the pockets where intramolecular hydrogen bonds are to be formed. You may notice ...


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The functional implications of the biconcave shape of human red blood cells are not fully understood. Several hypotheses have been suggested as explanations, including bending energy (1) and effects on oxygen transport (2). More recently, it has been hypothesized that the shape is important for the flow properties of the blood cells in capillaries. Uzoigwe ...


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Many cell components are not simply hydrophobic or hydrophilic, but have dual affinities. Proteins typically have structures which result in the interior of the protein being hydrophobic and the exterior, which is exposed to the water in the cytosol, being hydrophilic. Thus, differences in polarity between different regions allow proteins to be dissolved in ...


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Actually, for your example it would be pretty easy to adapt. You just have a 25.5 hour day with 12.75 hours of day and 12.75 hours of night. Except you have a 4.25 hour period in the middle of the day where you stay inside and use lights (like in the evening for most people on Earth) and a 4.25 hour period at night where you make sure your eye mask is on. ...


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Humans have evolved for 24 hour days and our bodies would not adapt well to this short of sleep/wake cycles (whether or not they were born there, unless they have been there for many generations and have been able to evolve for the new time). Our bodies would still want to spend about the same amount of time sleeping and being awake. If we tried to adjust ...


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Unfortunately, that isn't a very well-written problem, but I think I can help. If we assume simple Mendelian genetics, this would be a monohybrid cross, as you're only examining one trait (flower color). You have a pure-breeding white flower and a pure-breeding red flower. These make up the P (parental) generation. Their offspring will be the F1 (first ...


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Assuming that red is homozygous dominant and white is homozygous recessive, this may help you: http://faculty.ucc.edu/biology-rohrer/Bio112_Files/mendel-punnett.pdf


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I think one would not have a lot of success using a filter to do this, rather using a centrifugal gradient and comparing the fractions to a standard I think would be preferable. Nitrocellulose filters are made with precision but not very astounding accuracy which is the main reason they are commonly used at set sizes (like 0.2 and 0.4 microns) and not often ...


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The processes that occur at the ER membrane in eukaryotic cells take place directly at the bacterial plasma membrane. Phospholipids are synthesised and inserted at the plasma membrane, and there is a protein translocation apparatus for translocation of proteins into the periplasmic space and insertion of transmembrane proteins into the plasma membrane.


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Short answer Yes that would work in the condition that the trait you select for (size) is heritable. Long answer The kind of selection you would apply is called truncated selection because you fix a limit in size (depends on your filter) under which individuals do not survive and above which individuals survive and reproduce equally. The response to ...


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What you're referring to as a mosquito bite is actually the "wheal" (red swollen bump in the skin) that forms from an immune system reaction to antigens (foreign molecules) in the saliva of the mosquito that it leaves behind inside the bite. It's not technically a toxin, just something that causes an immune reaction. It's also not an infection, it's ...


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First thing to make clear is that net $6$ $H_2O$ go out of the reaction.($12$$H_2O$ $-$ $6$$H_2O$) Let me tell you my calculation, you should then be able to figure out what went wrong. For the Left hand Side, $6$ $H_2O$ are accounted here : $2$ $H_2O$ go in conversion of 2-Phosphoglycertae to phosphoenolpyruvate. $2$ $H_2O$ in TCA from conversion of ...


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This is highly unlikely because the immune system would detect these cells and atack them as foreign. There is at least one case described in the literature in which a woman died of lung cancer after receiving a donor organ from a smoker. This is due to the fact that after transplantations people have to take drugs to suppress their immune system to avoid an ...


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Broadly speaking, nutrients that enter the blood from the gut, and those that are released into the blood by the liver, are available to any cells that require them. So there is no "guiding to the correct location" in the sense that you suggest. Lipids for example are present in the various lipoproteins and can be acquired from these by all cells. Iron is ...


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A conserved pathway is a pathway that exists in a variety of species, by virtue of that pathway being conserved throughout the evolution of those species. A pathway must by neccessity have appeared for the first time in one particular species. If that species gives rise to new species, but the pathway in question is identical or very similar in all the new ...


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Pavement cells should content you: From http://dev.biologists.org/content/131/21/5215.full


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Membranes are built from a specific class of lipids, namely phospholipids, whose key property is that they are amphiphilic and so can self-organise to form bilayers. Not all amphiphiles do this, some prefer to adopt a micellar organisation. A bilayer composed of phospholipids produces the ideal combination of a hydrophobic barrier with a hydrophilic surface. ...


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"Let's say and acidic solution triple what you would find for a "corn", with and alcohol content of 14% by volume and salt 3.6% by volume of the two liquids?" cell death and tissue death, person death. All 3 of these conditions you cite are fatal to cells under the skin. A blood Alcohol level of 0.5% w/v is fatal. In the digestive tract its okay and on ...


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cool pics! Firstly, Formadahyde is a terribly toxic substance. Skin Contact: CORROSIVE. Contact can cause pain, redness, burns, and blistering. Permanent scarring can result. Can be absorbed through the skin. Formaldehyde causes organ failure and scarring if ingested. In this case, since you don't have burning or blistering, it seems like a ...


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Irrigation at the injection site and most likely tissue damage. Alcohol, salt and also acidic solutions can damage cells. And since the injected solution is not sterile, it can also cause infection. Either at the injection site or also more systemic like a blood poisoning. Nothing to test.


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The lipopolysaccharide layer of the Gram-negative bacterial cell wall is stabilised by divalent cations. Most recipes for disrupting E. coli cells include Tris-EDTA for this reason. I seem to just know this, so no reference at the moment. All nucleases require Mg2+, which is why there is EDTA in the stop buffer added to restriction digests. Carry-over of ...


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Lewis & Engelman (1983) Lipid bilayer thickness varies linearly with acyl chain length in fluid phosphatidylcholine vesicles. J. Mol. Biol. 166: 211 - 217. Table 1 and Figure 3 have the information that you need. For C14:0 the thickness of the hydrocarbon bilayer is given as 23 Å. Just in case this is homework, I'll leave you to convert that to ...


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A lot of enzymes need metal ion in their active center (it is actually the metal ion which is taking part in the catalyzed reaction). These are manganese, magnesium, copper and so on. For DNAses the metal in the active center is magnesium and EDTA simply chelates this ions, making them unavailable for the enzyme and thus hinders the enzyme from working. ...


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Underneath the superficial layers of your skin there are receptors which sense pressure, temperature and pain. These receptors are part of the peripheral nervous system which senses stimuli and they take the message conveying details about the stimulus to the somatosensory cortex of the brain. Here is where the perception of pain, burning, pressure etc is ...



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