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8

Yes, this is possible and is researched as an alternative to antibiotics. It has been used experimentally before antibiotics became widely available. Research was abandoned when antibiotics became widely available. See for example here and here for reports on this. Today bacteriophages are researched for the treatment of bacteria which have a lot of ...


8

DNA in the body is not available as a free molecule, it is organized around DNA binding proteins, mostly the histone octamers. These proteins carry positive charges (mostly from lysine side chains) which interact with the phosphate backbone of the DNA. It is like in the figure below, the charges play an important role in the tight packaging. See here for ...


6

I was musing on this and did some strange googling, and have some ballpark figures for a bunch of different organisms. It's far from a complete answer but it's at least a start, and all this won't fit in a comment. DNA replication, I assumed, was a huge metabolic drain on the cell. Turns out that is far from the case. Many helicases are passive, requiring ...


5

High intracellular glucose. Affects: all cells that do not depend on insulin to take in glucose. Examples: neurons [1], kidney cells, retina cells. Causes: high extracellular glucose (in most cases hyperglycemia) Effects: promoting necrotic cell death through $H_2O_2$ (peroxide) formation, which may participate in the development of diabetic ...


5

A feedback loop is a network structure in which the gene is able to regulate itself via a single path. $A\rightarrow B\rightarrow C\rightarrow A$ Interactions can be called positive or negative depending on their effect on the downstream gene. If a gene A represses another gene B, then it is a negative interaction; when it activates then the interaction is ...


4

There are several, but I guess the most well known is the neuron action potential, where the concentrations of Na+, K+, and Cl- ions determine the membrane potential of the cell. When the potential reaches a certain level, it triggers the action potential. You can read about this in much more detail on wikipedia, ...


3

Yes. But it is incorrect to call mitochondria an organism now. Most of their genes were lost and are now encoded in the nuclear genome It gets most of its metabolites It is not known. See the other post for details. Why membrane: I guess you know that. Why folded: you guessed right. Only ovum donates mitochondria and other cytoplasmic factors. Sperm just ...


3

According to wikipedia, cardiolipin is found in two places, the inner mitochondrial membrane, and bacterial membranes. Given the endosymbiotic origin of mitochondria, it makes sense that they would retain some remnant of their bacterial ancestry. But more importantly, cardiolipin plays a role in the enzymatic functions of mitchondrial membranes. Cardiolipin ...


2

What one thinks, no matter how intuitive it may appear is not particularly relevant in science. The inductance associated with a neural axon has been well documented since Cole (1966). Its role in the propagation of neural signals is developed extensively in http://neuronresearch.net/hearing/pdf/7Projection.pdf#page=39 . The actual development begins ...


2

Since posting, I did some more research using background refs from the intro (who knew?). The trick seems to be that when protons are pumped out, the cell regenerates them from water in order to maintain pH. So the solute concentration DOES increase inside the cell with more Na/H transport.


2

The glucose can react with proteins, damaging them. This is called glycation. Note that glucose is the preferred body fuel and has a 10 fold lower ability to cause glycation than fructose. http://en.wikipedia.org/wiki/Glycation


2

Your cells have a high concentration of sodium ions that are positive. Other important cations are potassium and calcium. Additionally, many amino acids are positively charged at physiological pH. DNA is not the only source of negative charge in your body, other amino acids are negative, and most cell surfaces are negative as well. The interactions between ...


2

Positive and negative feedback are essential motifs that control transcriptional activity of genes. They may involve other genes, mRNA and/or proteins. A classical pattern of negative feedback is where transcription of a gene results in mRNA and translation of this mRNA in a protein that represses the expression of the gene again. Feedback loops may involve ...


1

The negative charge in DNA is localized to individual oxygen atoms in DNA. This negative charge is balanced by positive ions in the body. In the case of a magnet or molecules with a dipole, negative and positive magnetic field lines align to produce an overall magnetic field. DNA has many small dipole moments but none across the entire molecule. In the ...


1

Too much glucose leads to the formation of advanced glycated end products, which deposit in tissues like glomerulus and cause disease like diabetic nephropathy. Also glucose is osmotically active, so when it starts appearing in urine (because of its high levels in blood), it leads to polyuria, following which the lost water is recovered from body tissues, ...


1

Glucose transports from the blood into the cells via facilitated diffusion. This means that glucose goes from higher concentrations (in the blood) to lower concentration (in the cell). Therefore, if you have super high glucose concentrations in the blood, you will have a ton of glucose in the cells. Glucose will oxidize by itself, thus it will contribute a ...


1

A significant amount of heat generated by the cell does not come from the hydrolysis of an NTP. ATP is generated by a H+ gradient in the mitochondria, and this gradient is created by mechanisms which rely only in part by ATP. Most of the energy stores in our bodies are not in the NTP pool. This is why CO2 and urine are used to measure energy expenditure ...



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