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There is a very different mechanism for generation (and detection) of ultraviolet, visible and infrared light vs radio waves. For the first, it is possible to generate it using chemical reactions (that is, chemiluminescence, bioluminescence) with a typical energy of order of 2 eV (electronovolts). Also, it is easy to detect with similar means - coupling to ...

The carriers of the charge are ions and they get repelled from each other well enough. Other than their charge there is only the size in which they differ (for all practical purposes). This means, as long as we are talking about membrane potential, the actors are just a mix of 1+ ions which don't come near each other. When size matters, for example in an ion ...

This phenomenon is called depolarization block and it occurs in real membranes in current-clamp experiments. The key mechanism is that the membrane has not been allowed to repolarize sufficiently to relieve the inactivation of sodium channels. The Hodgkin-Huxley model reflects this in the "inverted" voltage-dependence of the h gate (sodium inactivation ...

(I probably ought to have a pat answer to this on the tip of my mind, but since I don't I'm going to wing it. This is probably just an opportunity to make an utter fool of myself. Please treat everything that follows with extreme suspicion.) I think this is effectively an artefact of the model. That may not be true in the strictest sense -- it is possible ...

Let's start with the basics. The inside of the cell contains predominantly positive potassium ions, and negative phosphate ions, and other negative ions (e.g. from amino acids). The outside of the cell contains predominantly positive sodium ions, and negative chloride ions. The cell however sets up a resting membrane potential, due to the cell's ...

These statements are not true, simply speaking. Currents as little as few microampers can kill a person if, for example, applied directly next to the heart. A few seconds of 220V can kill a person even if the current is in miliamper range (Biksom, cited below, mentions 4s at 120mA). However, it is true that it is not the voltage alone that kills, that there ...

I am not sure that kind of action would be a "significant influence", but the general understanding is that LFP and spike frequency are inter-correlated (1, 2). An interesting recent publication on the topic (3), however, doubts this correlation as the nature of LFP recording and signal processing might introduce some artifacts to the recordings. It would ...

Every atom produces a magnetic field, so the formally correct answer would be "yes" (assuming that viruses belong to the tree of life, which is disputed -- otherwise, one would not use the prefix 'bio'). However, biomagnetism as a science (and not pseudoscience) is concerned with more measurable effects. The biomagnetism of a virus will be negligible ...

Actually, electromagnetic communication is used by certain fish, the mormyrids and the gymnotids. Pulse modulated in the former and amplitude modulated in the latter. However, the frequencies used are not much greater than 1Khz, which is not what we ordinarily consider to be in the radio frequency spectrum. There is, too, another biological species in ...

A quick comparison between light and sound vs. Radio Light: Wavelength 380 nm -740 nm Sound: 17 mm - 17 m Radio: 1mm - 10e5 km From the Planck relation, the energy of a wave is inversely proportional to the wavelength. As a result light is stronger than sound which is stronger than FM radio which is stronger than AM radio. Very likely, the energy ...

Just to clarify your ion/electron question - a neutral atom or molecule becomes ionized when it either loses one or more electrons, becoming positively charged, or gains electron(s), becoming negatively charged. Since the negatively charged phosphate (PO42-) ions have a surplus of electrons, they (the electrons) are free to flow "up" the wire and to the ...

After talking to a few electrophysiologists, I found out that they have very diverse opinions. It seems that a common way of stabilizing the movement of the brain with respect to heart beat is to press the brain with some softish-rigid material like agar. Also, draining the CSF could help but then this cannot be done without sacrificing the animal. The ...