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Bernoulli's principle can be a little tricky when applied to the cardiovascular system, but it still holds true across the entire system. You mention a good point that the relationship doesn't seem quite right at the aorta or arteries, because of the constant fluctuation of pressure between systolic and diastolic without a significant change in diameter of ...


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Short answer Yes they can, but with less efficiency. Background Efficiency of sticking to a glass surface decreases about 20-fold when the gecko's feet are wet (Stark et al., 2012). On dry glass, Gekko gecko holds on with about 18 N, which is about 18 times their own body weight. Hence, the gecko attachment system is over-designed (Knight, 2012). Wetted ...


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I think there are several things that keep Bernoulli's principle from being straightforwardly applied. First, Bernoulli's principle would help us calculate the pressure exerted by the blood on the walls of the vessels, but that's not what blood pressure measures. Blood pressure measures the amount of force that has to be applied to stop the blood from ...


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Short answer The physiological state of the postsynaptic cell ultimately determines the effect of an incoming action potential. Background An action potential occurring in a chemical synapse is neither inhibitory or excitatory. An action potential is a binary '1', an-all-or-nothing signal without any information, i.e., there is not a -1 or +1 action ...


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well it's based on the tissue type for example take loose connective tissue which lies under epithelium they don't merge because of the profound matrix separating them while in the epithelium in cuboidal and columnar epithelium at side corner and upper portion of their membranes the two neighboring cells fused completely preventing any flow of material ...


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Phospholipid bilayers found in cells are usually negatively charged. The phosphate groups repel each other by like charges and prevent two membranes from coming too close to each other. Membranes are also full of proteins and often coated with carbohydrates, which serve to keep membranes from interacting too strongly. See this diagram of a membrane bilayer: ...


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Representative ion concentrations are shown in Fig. 1: The membrane is mainly permeable to K+. Because the Na+,K+-ATPase pumps K+ inside of the cell, it tends to diffuse outward again, thereby taking positive charge outside the cell and making it negative inside (extracellular space is pretty much devoid of charge due to its vastness). Because the ...


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I can't add any detail to AliceD's answer, but I can put it in different terms, and perhaps that could be helpful to you. Yes, Cl- ions are negatively charged, and the neuron is very often negatively charged. Given only those two facts, yes, you would think Cl- would not enter the neuron. But there is another key fact: diffusion. The Cl- ions feel the ...


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Nanodiscs are very powerful technology for membrane protein invented in Stephen Sligar's lab at the University of Illinois. A nanodisc is composed of a membrane protein, lipids and two monomers of a "scaffold protein". The most used scaffold protein is an N-terminal truncation of apolipoprotein A-1 (apoA-1), which is the primary protein component of ...


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This has been studied by some of my labmates in Why is the biological hydrophobicity scale more accurate than earlier experimental hydrophobicity scales? I am not involved in their research, but here is the gist of the paper: Different scales are, as you say, developed based on different criteria. In particular, Eisenberg scale is one of the consensus ...



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