Questions tagged [ph]
pH is a measure of the acidity of a solution. It is defined as the negative logarithm (base 10) of the concentration of hydronium ions in a solution.
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Carbon dioxide concentration in alkaline media
I am running a batch experiment using penicillin bottles where I have bacteria growing for 21 days in a highly alkaline media (pH 10). I am measuring the CO2 and O2 content in the headspace over time, ...
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[IAL Biology]: Struggling to understand how pH and temperature affect haemoglobins affinity for oxygen
As seen in the graph above, why do we say that increasing pH increases haemoglobins affinity for O2, but decreasing pH reduces its affinity? If the pH increases above or decreases below haemoglobins ...
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Will eating candy with a lower ph than the stomach increase stomach acidity in the short term?
The average stomach ph is 2.5.
Some candies have a ph that is lower (more acidic) than that.
Will eating candy with a lower ph than the stomach increase stomach acidity in the short term?
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Why does pancreatin affect the pH of milk? [duplicate]
I just finished a lab for college and I was really intrigued by this. Since we're in a rush to finish the semester on time my professor didn't go into details much she just said something about fatty ...
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Influence of pH on rennet coagulation of milk [closed]
I was looking for the reason why rennin works most efficiently at pH 6.7 (closer to a neutral environment than acidic).
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Can distilled / deionized / demineralized water "attack" teeth?
Demineralized water is claimed by some resources to be highly aggressive (due to their lack of minerals) and to attack all sorts of materials. From the World Health Organization website:
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How to measure the pH of a bacterial species?
I would like to calculate the pH of a certain bacteria species before after an experiment. I was reading about the pH cell of bacteria and I found out about Bacterial Intracellular pH which I ...
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Biology Experiment Algae pH & temperature help?
I am planning a Biology investigation for my IB IA on the impact of temperature and pH on algae growth. Does anyone have tips on how to measure the growth rate of algae? What algae is the most suited ...
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The effect of low pH on HIV virus
I've read a couple of articles that state that HIV is an enveloped Retrovirus that is so sensitive to the acidity of the environment and it cannot survive or will be inactivated at pH below 7. What ...
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Is there any correlation between animal diet and blood pH?
The alkaline diet claim that as we humans have a slightly basic pH we shouldn't eat acidic food like meat (I think they claim that meat ashes are acid).
I was wondering that if carnivores animals ...
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Binding BSA to silver surface via large difference in isoelectric points of the two materials
I would like to bind BSA to a silver surface so that I can utilize plasmonic sensing to detect the BSA. There seems to be two methods of doing this: 1) to rely on electrostatic forces or 2) to form a ...
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PDB id to protein environment ph [closed]
How can one find the information of a protein environment ph from its PDB id?
Can one assume the ph to be the same as its cellular location?
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What is blood pH for different animals?
So we all know that humans average blood pH is 7.4. But is it the same for the animals?
I need examples of animals with the same blood pH as humans and the ones with different blood pH.
I guess dogs ...
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What pH ranges are used in industrial scale fermentation?
When reading
Hans-Peter Meyer, Wolfgang Minas, and Diego Schmidhalter (2017) Industrial-Scale Fermentation. Industrial Biotechnology: Products and Processes, First Edition. Edited by Christoph ...
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Why is it possible to make yoghourt with lactose-free milk?
The function of the Lactobacillus bulgaricus and Streptococcus thermophilus cultures is to ferment lactose to produce lactic acid. The increase in lactic acid decreases pH and causes the milk to clot,...
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Why does dissociation of carbonic acid cause a decrease in pH?
When a molecule of carbonic acid (H2CO3) dissociates, the two products are a bicarbonate ion (HCO3-) and a hydrogen ion/proton (H+). Because of the addition of a hydrogen ion, this process causes a ...
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What is the role of lactic acid bacteria (such as L. acidophilus and L. bulgaricus) in glycolysis during yogurt fermentation?
I am trying to prove that an increase in monosaccharides (glucose, fructose, galactose) that have been added to milk during fermentation will result in a decreased pH. My current argument is:
"The ...
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What happens to Bacteria at a low pH?
I am conducting an experiment on how different pH levels effect the growth of E.coli. After researching, it is predicted that the most acidic pH level (pH 2) will be most effective at killing (or at ...
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What are the (statistically) normal pH levels in the most-outer part of human sexual organs?
What are the (statistically) normal pH values of the outer skin/epidermis of human sex organs (groin/crotch) in the male and female? e.g male testes, female vulva, male glans, the enveloping epiderm, ...
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Acidity and Alkalinity of Foods
Some foods leave an acidic effect on the body such as meat and dairy, while others leave an alkaline effect, like vegetables. However, are these effects significant enough to greatly alter the blood ...
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What is the pH of the mitochondrial intermembrane space?
The proton gradient is stored between the mitochondrial double membrane. More protons mean more hydronium ions and lower pH, but how much exactly?
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HELP! How will pH 14 affect enzyme structure? [closed]
If a substance is very alkaline/ basic, e.g. a pH of 14, does this mean that there are near to zero H+ ions (or it is possible to have such a situation where there are zero H+ ions and it is still ...
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Alternative to distilled water for pH test
I am looking to test soil pH in a remote location. The test results don't need to be perfectly precise, and a pH test strip should provide sufficient accuracy. However generally this kind of testing ...
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What is the resting human stomach pH?
This article in ThoughtCo.com claims we have a resting stomach pH of 4-5.
Unfortunately, there are no references, so I can't verify what it says.
I am slightly confused, however. The study says
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How do I know which molecular structure is glycine's "base state"?
I was looking up the chemical structure of glycine, and I found the following two images:
and
.
My question is, what is the "base state", or the "natural state" of glycine? Under what scenarios ...
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What does a typical, perfectly healthy vaccinium corymbosum (highbush blueberry) leaf look like?
What does a typical, perfectly healthy vaccinium corymbosum (highbush blueberry) leaf look like?
Colour (darkness of green, redness)
Waxiness
Veins
I'm guessing that soil ph, nutrients, and other ...
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Deionized water - can it be beneficial for metabolic acidosis?
I ran into an interesting question today that examined the science around alkaline water and its advertised 'generalized health benefits' assumed to be (but incorrectly) stemming from a rise in blood ...
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Determining net charge of amino acid at given pH
I am trying to calculate the net charge on an amino acid, but I seem to be doing it wrong. The question I am trying to answer is "In a pH 7.0 buffer, what will be the charge of Methionine?" ...
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Why does the pH decrease, when adding pancreatin to different types of milk (cow milk, soy milk etc.)?
I'm experimentally observing how pancreatin affects the pH in different types of milk.
Why does the milk's pH decrease when I add an enzyme solution to different types of milk (e.g., cow milk, soy ...
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The effect of pH on catalase
Why does catalase still produce oxygen when mixed with 1 mL of 0.1M NaOH (pH 13), but not when mixed with 1 mL of 0.1M HCl (pH 1)? Catalase's ideal from what ive researched is 7. In other words, since ...
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Do the pH and other ions affect the hydrolysis of ATP
ATP hydrolizes to ADP and phosphate in a strongly exergonic reaction and is used for energy transfer and short-term storage in cells.
ATP is stable inside a cell, so a significant activation energy ...
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Catalytic Triad of Serine Proteases
Is serine considered an acid in the catalytic triad involved in the mechanism of action of serine proteases? It is donating a proton to His but I am not sure if this really qualifies as an acid?
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Chart of blood pH across different animal species?
How does blood pH vary across species? I can't find an article or chart listing this kind of information.
So far I've found bits and pieces like:
Human blood pH is nominally 7.4.
7.4 seems to be a ...
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How do you calculate the charge on a polypeptide chain with changing pH?
I understand the charge placement on the N & C-terminus and also the utilization of the R-side groups in the amino acids.
For example,
What is the overall charge for a chain Glu-Cys-Arg-Asp with ...
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Why do you die if you cannot breathe?
I was wondering what the actual reason for death by suffocation is. Obviously it is related to oxygen deprivation. But what is the underlying cause of death?
Is it due to insufficient oxygen for ...
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Blood pH at Higher Altitudes
My Campbell's Biology Textbook says the following:
"For example, when an elk or other mammal moves up into the mountains from sea level, physiological changes that occur over several days ...
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What are the metabolic concerns associated with hard water?
If humans can maintain a consistent blood pH, then what problems does alkalized water cause us?
Why is it recommended that we filter and boil hard water? Is the issue that hard water can affect the ...
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Does pH affect Michaelis constant?
I have been trying to confirm the Km of a substrate (which is 34 +/- 4 mM). This value was obtained in 50 mM MOPS, pH 6.3. I conducted my kinetics assay in a buffer of pH 7 and obtained a Km value in ...
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Is there a biological environment that we can we assume glutamate exists as glutamic acid?
In the body we almost always assume that glutamate exists as glutamate rather than glutamic acid. It is so commonly glutamate yet glutamic acid and glutamate share the abbreviations of Glu and E. From ...
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How do I prepare a solution? (Calculation) [closed]
I have to make 100mL of 400mM NaOH. How do I go about calculating what I need to prepare this?
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Why does pH have an effect on enzymes?
I am currently studying biology and would like to know why enzymes work best in a particular narrow range of pH (the so-called pH optimum).
Unlike temperature change, I do not think this has much to ...
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What are the highest and lowest possible pH, paCO2 and HCO3 in the blood of living human?
What are the highest and lowest possible values of pH, $paCO_2$, and $HCO_3$ in the (arterial or venous) blood of a living human being?
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How do fish tolerate pH changes in water?
I want to know how aquatic animals behave as a natural indicator of the acidity in lakes and rivers.
How do they tolerate these pH change?
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Effect of pH on life? Use buffer or HCl? How about lactic acid?
I'm trying to find the effect of pH on living things like E. coli and such. At first I thought of using a buffer solution which maintains its level of pH, but it's possible that the inactive ions of ...
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How Do Acid and Base Loving Plants Get Enough PO4?
Acidic and Basic soils experience phosphate sequestration through binding with either calcium, aluminum, or iron. How do plant that thrive in acidic and basic soils obtain the necessary phosphate? ...
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