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9 votes
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Determining net charge of amino acid at given pH

You are right in your reasoning: at any pH for any titratable group, there is a distribution between the protonated and deprotonated species. We can calculate this distribution and therefore the ...
canadianer's user avatar
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5 votes

Can distilled / deionized / demineralized water "attack" teeth?

Here is a list of mineral dissolution rates in pure water. they ALL dissolve, even quartz. The figure for quartz is 4 × 10−14 mol/m2s at 25'C: https://pubs.usgs.gov/of/2004/1068/pdf/OFR_2004_1068.pdf ...
bandybabboon's user avatar
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5 votes

How do I know which molecular structure is glycine's "base state"?

Short Answer: You need to define base state. Background: The point to keep in mind here is that the base state (as you call it) is not constant. As @jeppenielsen points out in the comments, amino ...
another 'Homo sapien''s user avatar
4 votes

Acidity and Alkalinity of Foods

Extracellular acid base homeostasis in human physiology is maintained primarily by the bicarbonate buffer, as regulated by both the kidneys and the lungs (and to a certain extent, the intracellular ...
De Novo's user avatar
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4 votes
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Why is it possible to make yoghourt with lactose-free milk?

Conversion of lactose to galactose and glucose is a part of the bacterial metabolism of lactose. So digested lactose would work. In fact, it should work for all kinds of 6-carbon sugars as lactic ...
WYSIWYG's user avatar
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3 votes
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How to measure the pH of a bacterial species?

The pH level of the Bacterial Intracellular structure is different from the pH level on the eternal side of the cell. Moreover, there are no studies that suggest that a change in the external pH of ...
Anwar Elhadad's user avatar
3 votes
Accepted

What happens to Bacteria at a low pH?

pH affects the structure of all macromolecules that compose bacteria, and indeed all cells. Here's a shortlist of examples: Lipids Lipids are hydrolyzed by extreme pH levels. They undergo chemical ...
S Pr's user avatar
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3 votes

What is the pH of the mitochondrial intermembrane space?

According to the authorities Roos and Boron the difference of pH across the inner-membrane of mitochondrion is 0.5 with pH outside the membrane equal 7.0 and inside the pH is 7.5 (pH-mit = 7.5, pH-...
alina's user avatar
  • 79
2 votes

The effect of pH on catalase

The pH profile of an enzyme is not necessarily symmetrical. As random examples, see Figure 7 here, or Figure 5b here. Or if you have access, a pH profile for Magnaporthe grisea catalase can be seen in ...
R.M.'s user avatar
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2 votes
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Why does dissociation of carbonic acid cause a decrease in pH?

Any acid that releases a proton when it dissociates in water will also produce a conjugate base. We can conceptualize this as $\ce{HA <=> H+ + A-} $. In this particular example, $\ce{HCO3-}$ is $...
De Novo's user avatar
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2 votes
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What is the pH of the mitochondrial intermembrane space?

I agree with @alina that it is well accepted that the pH difference across the inner membrane is ~0.5-1 units. However, the absolute value of the pH in the IMS will vary between organisms and even ...
Katuyci's user avatar
  • 136
2 votes

Alternative to distilled water for pH test

The h2co3 content of unadulterated rain is 15 micromoles of H+/Kg at room temp. The pHBC of average field soil from a 3000km transect in asia varied from 10 to 188 - mmol-kg-ph unit... from 40 ...
bandybabboon's user avatar
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2 votes
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What pH ranges are used in industrial scale fermentation?

Fermentation pH will differ a great deal depending on the bacteria or fungi being used and the process. But it is not uncommon to have a relatively narrow range of pH as a target. Remember pH is the -...
Sam's user avatar
  • 191
2 votes

Binding BSA to silver surface via large difference in isoelectric points of the two materials

Concerning the apparent discrepancy between your first and second citations, the difference in values is addressed by the authors in the more recent work: Perusal of the literature yields few IEP ...
acvill's user avatar
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1 vote

[IAL Biology]: Struggling to understand how pH and temperature affect haemoglobins affinity for oxygen

I think you might be misunderstanding the term affinity, which is a measure of how strongly the two molecules (for example, haemoglobin and oxygen) bind to each other. High affinity means there is a ...
Domen's user avatar
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1 vote

Biology Experiment Algae pH & temperature help?

In general is a good idea to check the scientific literature in the subject. In the section "materials and methods" you could find how people do stuff like measuring growth or controlling pH....
heracho's user avatar
  • 737
1 vote

PDB id to protein environment ph

I know that ENSEMBL, PDB and the Human Atlas give known locations for many proteins at different levels of certainty, but such data is far from complete. Also experimental indication of a proteins ...
KaPy3141's user avatar
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1 vote
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HELP! How will pH 14 affect enzyme structure?

This is a very chemical explanation. Here goes. $\ce{pH = -log[H+]}$ $\ce{pOH = -log[OH-]}$ $\ce{pH + pOH = 14}$ Therefore, at a $\ce{pH}$ of $14$, $\ce{pOH}$ is zero, so there is 1 mole of $\ce{...
JSCoder says Reinstate Monica's user avatar
1 vote

Alternative to distilled water for pH test

Rainwater might not be the best option. Rain water is naturally acidic due to the reaction of CO2 forming some weak carbonic acid [see here for explanation]. Source: Wikipedia As a result, pH ...
theforestecologist's user avatar
1 vote
Accepted

What does a typical, perfectly healthy vaccinium corymbosum (highbush blueberry) leaf look like?

Vaccinium species are ericaceous plants (acid soil loving) so they will not do well in alkaline soils, and/or being watered with hard water. In fact they have a narrow optimum pH range 4.8 - 5.2 (...
Martin Hügi's user avatar
1 vote

Why does the pH decrease, when adding pancreatin to different types of milk (cow milk, soy milk etc.)?

the pancreatic fluid contains lipase which breaks down the fat in the milk in to fatty acids and glycerol. The fatty acids produce lower and create a more acidic pH.
Anna's user avatar
  • 19
1 vote

Do the pH and other ions affect the hydrolysis of ATP

OK. Let’s answer the questions you pose: How does the pH affect the hydrolysis of ATP? High concentrations of hydrogen ions or hydroxyl ions (“extremes of pH” — as you quote) cause acid or alkaline ...
David's user avatar
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1 vote

Do the pH and other ions affect the hydrolysis of ATP

Stability of ATP is largely due to Mg2+. ATP in cell is actually Mg2ATP2- The Mg ions stability the negative charges on the phosphates. pH is also important of course, but Mg is key, hence you see Mg2+...
SciEnt's user avatar
  • 407
1 vote

Catalytic Triad of Serine Proteases

It depends how you define an acid. For what it‘s worth, the chemical definition Google presents when I search is “a molecule or other species which can donate a proton or accept an electron pair in ...
David's user avatar
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