Hot answers tagged biology
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Moving at a constant velocity, no matter how close to the speed of light, has absolutely no effect on the person moving. In fact, it has no effect on the laws of physics. This is the fundamental tenet of special relativity - you cannot tell absolute motion, only relative motion between different things. The changes you are referring to are what someone ...
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There is clearly no universal answer. One would have to say what living things, and in what state, have been introduced.
Life forms are generally capable of reducing their own entropy, but of course they increase the entropy of their environment by an even larger amount because no one, not even life forms, have the right to violate the second law of ...
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The Gibbs Free energy is not defined as ∆G = ∆H - T∆S. That holds only at constant temperature. It can be defined as $\Delta G = \Delta H - \Delta (TS)$. For a reaction to be spontaneous at constant temperature and pressure, $\Delta G$ should be negative. However, all reactions go to a certain extent, even if only microscopically. Basically a $\Delta G$ ...
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Yes. Endergonic reactions are happening, for instance, in any place where water is naturally freezing into ice. In the surface of a lake for instance.
As you state, any endergonic process happens always coupled with an exergonic (the atmosphere air above the lake is pumping enthalpy away from the lake). But, if you consider the lake together with the nearby ...
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I'm only going to try to address the question of DC fields.
Medical MRI uses uniform fields of about 0.5 to 3.0 T. In a head MRI, the Lorentz force on ions in the brain can cause neurological effects such as vertigo. I've heard that this shows up in particular when the patient moves his head.
Here is a famous picture of a frog being levitated by a 16 T ...
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One simple approximation that you could make is to assume that the human body is made of water. Then you can reduce your question to: what happens to water molecules in a magnetic field. Consequently, you would have to ask how you can break the Van der Waals Bond in water with a magnetic field.
I think here you would have to differentiate between a static ...
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I don't think the formation of lipid bilayers is analogous to the Casimir effect because it's a surface energy effect. However there is an effect called depletion flocculation that is very closely analogous. This happens in a polymer solution when surfaces approach more closely than the size of the polymer molecule. The polymer is excluded from the region ...
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The answer to the valve-question,1 according Pilotfriend, seems to be the "floppy walled Eustachian tubes".
During ascent the gas (air) in the middle ear cavity expands and a small amount of pressure builds up against the ear drum causing them to bulge outwards ever so slightly (that ‘fullness’ you feel in your ears just before they ‘Pop’). This pressure ...
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The $Q_x$ and $Q_y$ transitions are electronic excitations in the conjugated $\pi$ orbitals of the Bchl a molecule. They involve two different sets of conjugated bonds. The $Q_x$ involves a shorter chain of conjugated bonds so it occurs at a higher energy/frequency. I couldn't find a really good diagram to show which bonds are involved in the in the $Q_x$ ...
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First let us see the impact of gravity on plants: Gravitropism (also known as Geotropism) is a turning or growth movement by a plant in response to gravity. Roots show positive gravitropism and stems show negative gravitropism. That is, roots grow in the direction of gravitational pull (i.e., downward) and stems grow in the opposite direction (i.e., ...
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There are many good books on this topic. Here are two of the best which is a good place to start if you want to seriously begin to understand the topic.
The first is by one of the world's greatest theoretical physicists, Roger Penrose who has written extensively about consciousness:
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