Questions about the application of chemistry to interrogate and modify biological systems and processes.

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2
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0answers
7 views

Thermal stability of charged and uncharged alpha helices

I just learned that charged alpha helices are less thermally stable than uncharged ones. The only difference I see between them would be a larger dipole moment in the charged helix, but how would this ...
1
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1answer
24 views

How does repeatedly freezing and thawing antibiotics decrease their antimicrobial effectiveness?

This is something I have read on forums repeatedly, but I don't understand the mechanism behind how antibiotics lose their effectiveness. I understand how repeatedly thawing and freezing cells would ...
4
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0answers
36 views

Preservation and bleaching of sliced mushrooms with hydrogen peroxide

According to the article Extending the Shelf Life of Fresh Sliced Mushrooms, it states that 5% (v/v) hydrogen peroxide is an effective means for the preservation of sliced mushrooms. In regards to ...
3
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0answers
857 views

How long would it take to dissolve someone using fluoroantimonic acid? [closed]

After writing an answer on worldbuilding.SE, I came here to ask a question. How long would it take to dissolve a human body using fluoroantimonic acid? I understand that since the human body isn't ...
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0answers
20 views

Chemical incompatibility between aluminum hydroxide [Al(OH)3] and carbomer polymer [-CH2-CH] N-COOH]

I am currently adsorbing proteins to an aluminum hydroxide gel. By adding a carbomer (polymer of acrylic acid cross-linked with allyl sucrose), I achieve a somewhat synergistic formulation. Shortly ...
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2answers
197 views

Why carbon monoxide has a greater affinity for Hemoglobin compared to oxygen?

Hemoglobin is an iron-containing oxygen transport metalloprotein in the red blood cells of most mammalians. Simply put it's a carrier protein. Interestingly it doesn't carry carbon dioxide the same ...
2
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2answers
104 views

Confusion about PCR

I seem to be getting two different answers from my book and my teacher about PCR. Does PCR require a double stranded piece of DNA that you are tryig to replicate, or does it require a circular piece ...
3
votes
1answer
36 views

Why does solid phase peptide synthesis (SPPS) always proceed from the C to the N terminus?

Is it just for historical reasons? Because the first person who did it decided to attach the C-terminus to the solid support? Or are there chemical reasons why it would be impossible to proceed in ...
5
votes
1answer
225 views

Benzaldehyde and Cyanide - if you can smell one can you smell the other?

Cyanide and benzaldehyde both have an almond-like smell. Some people cannot smell cyanide (specifically, HCN). Can they also not smell benzaldehyde? In other words, do they both trigger the same ...
3
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1answer
42 views

Advantages of thioesters over esters in fatty acid catabolism

In several metabolic pathways, Nature (live systems) chooses to make esterification using thioesters (CoA) and not esters. I would like to know what is the main aim of the Nature with this choice: ...
2
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1answer
30 views

pH effect in the hydrophobic interactions between two polypeptide chains

The rise in pH can change the protein conformation by changing the ionic interactions and hydrogen bonds between two polypeptide chains. This is a fact that I understand very well because the change ...
5
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1answer
934 views

Has a non-carbon-based form of life been discovered since 2010?

In 2010 NASA announced the discovery of microorganisms that, after being treated in laboratory, could keep growing only using arsenic, instead of the (though very small amount of) phosphate they also ...
5
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3answers
346 views

Why amino acids (Zwitterion) become either negative or positive at low and high pH solutions?

The amino acids are Zwitterions. In neutral pH, an Amino acids' amino group has a + postive charge and Carboxyl group has - negative charge. They cancel each others charge thanks to the H that's ...
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0answers
33 views

How is the chemistry of the genetic code located on DNA related to the macromolecules in your body? [closed]

How is the chemistry of the genetic code located on DNA related to the macromolecules in your body?
4
votes
2answers
410 views

When an enzyme is diluted with water, what is slowing down the rate of reaction?

I'm specifically talking about the decomposition of hydrogen peroxide by bovine catalase. The number of catalase molecule obviously doesn't change, so there's the same number of catalase molecule ...
3
votes
1answer
62 views

How is it that fructose has a different metabolic pathway than glucose but yet glucose is converted to fructose?

Fructose is described to have a different metabolic pathway (a more fat-inducing one) than glucose (see: http://healthyeating.sfgate.com/difference-between-sucrose-glucose-fructose-8704.html) as it ...
13
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3answers
157 views

Is it possible to make a drug that liquefies heart plaque to treat heart disease?

Is it possible to make a drug that liquefies heart plaque to treat heart disease without damaging other parts of the body? If so, would the liquefied plaque be eliminated as regular fluid is through ...
0
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0answers
38 views

Is carbohydrate alcohol inebriant?

First of all, though I think that my question is related to this society, if you think reverse, tell me to delete the question: I would like to know if carbohydrate alcohol is inebriant; Can anyone ...
2
votes
1answer
90 views

The meaning of different parts in the naming of glucose

There are two main types of glucose, $\alpha$-D-(+)-glucose and $\beta$-D-(+)-glucose. Can anyone please explain what is $\alpha$,D or (+)? So (maybe by permutation and combination), how many types ...
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3answers
56 views

Biochem Book age and suggestions [closed]

I'm taking chem classes, and am interested in learning a some biochem on the side, on my own. I've bee looking for a decent book, though I'm on a bit of a tight budget so not brand shiny new ones ...
2
votes
1answer
62 views

Maltose Nomenclature

Maltose has a 1,4 glycosidic linkage between two molecules of α-D-Glucopyranose. My textbook suggests the final name of maltose as 4-O-(α-D-Glucopyranosyl)-D-glucopyranose I wanted to know ...
0
votes
1answer
48 views

What is a triglyceride?

I'm confused on what a triglyceride is, from what my text book it says its a type of gylercide, then from a website it said Glycerides can be subdivided into two categories. The first group, the ...
0
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1answer
30 views

Is it possible to identify the source of a protein hydrolysate [closed]

I have a powder which only declares to be "Protein Hydrolysate" Meaning that the all the protein has been broken down. We've tried to identify the source of the powder with DNA research. But no ...
4
votes
1answer
412 views

What are the biochemical ramifications of ingesting of distilled water?

Are there any distinct biochemical reactions that are affected by the ingestion of distilled water? The water is "distilled" in its literal sense.
2
votes
1answer
182 views

Why and how does lycopene absorbance increase with heating?

Lycopene, which is a carotenoid and a phytochemical is the main reason for why tomatoes are radio-protective. Source 1 . Source 2 Let's cut to the chase: I was wondering if this claim of The ...
7
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1answer
97 views

Is Acrylamide carcinogenic? Why?

Recently concerned with health effects by common chemicals existent in food I've been rather busy reading article after article; and just an interesting one came around: Acrylamide (or acrylic ...
5
votes
1answer
616 views

CO poisoning - What I've been taught is a hoax?

In elementary school, I happened to ask my teacher: What is $\ce{CO}$ they talk about these days? I was then taught that Carbon monoxide "competes" with the oxygen in our blood (we were taught ...
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2answers
957 views

Are all amino acids except glycine chiral compounds?

Specifically, I was thinking of the case where the R group is a carboxylic acid functional group or an amine group. Then there would not be a chiral carbon atom. Is there a restriction on what can be ...
3
votes
1answer
129 views

what would happen if you got a full package of wet silica gel on your hand after it tore open? [closed]

I accidently opened a bag of silica gel and got it on my hand what will happen to my hand because now it kinda feels weird.
4
votes
3answers
125 views

Can a single monomer be a macromolecule? If so, when?

In our science class, we're learning about the four fundamental macromolecules in every living organism: carbohydrates, proteins, lipids, and nucleic acids. Our class definition of a macromolecule ...
2
votes
1answer
161 views

What compounds exist in the bitter peel of specific fruits?

Actually, my original question was: What makes a pith of pomegranate so bitter? Then I decided to be more generic. You'll hardly find someone that consumes pomegranate and doesn't nag about the bitter ...
2
votes
2answers
84 views

Same monomers, different water content?

We're currently studying "the chemistry of contact lenses", which is mostly polymers and gels. I just looked at the package of two pure hydrogel lenses made out of the same monomers, but they have ...
0
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1answer
55 views

Aspartame poisoning: Can it modify aminoacids?

I just accidentally closed a webpage (and did not find it later) which described that somehow, Aspartame poisoning victims had faults in the vital proteins of their body due to the reaction of ...
18
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3answers
2k views

Why is methanol toxic?

There are two points of view for the answer of this question: The biological view, the only one that I faced during my research, states that since it can trigger perilous conditions like metabolic ...
0
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1answer
22 views

Mass of sucrose solutions

What is the mass of 150 ml of 40% sucrose, and what is the mass of 150 ml of 20% sucrose? I don't know exactly how to figure it out without using a device to tell me the mass. All I know is the mass ...
3
votes
2answers
142 views

Mixing of powders to make stock solutions

For a solution such as: Luria-Bertani (LB) Broth: 10 g tryptone 5 g yeast extract 10 g of NaCl ($M = 58.44\ \mathrm{g/mol}$) q.s. to 1 l, pH to 7.2, autoclave. I would like to make a bulk amount ...
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0answers
33 views

Enzyme Assay - pectinase

I am working on Enzyme Assay.I assayed the enzyme in different buffers from $pH\ 1-12.5$ However,the enzyme has good activities starting from $pH\ 1-10.5$ Is that possible to have enzyme activity in ...
1
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1answer
56 views

If dark surfaces absorb/store more light/energy than light surfaces, then does dark skin, on average, store energy from light most efficiently?

If darker surfaces absorb/store more light/energy per square inch than light surfaces, then does dark skin, on average, store energy more efficiently than light skin? (edited).
1
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1answer
120 views

Pectinase enzyme assay

I am working on pectinase enzyme assay. I incubated 900 ul of substrate for 10 minutes in the water bath, followed by adding 2ml of DNSA reagent, then 100ul of enzyme extract added finally i read the ...
2
votes
2answers
487 views

What is the difference between protein domains, motifs, and supersecondary structures?

I was just wondering if there is any difference between supersecondary structure and motifs. As well, is a protein domain an independently folded region of a protein that has a particular function ...
1
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1answer
21 views

in which way calcium promotes cell division

I have read in bio chemistry that calcium plays an important role in the cell division but the in depth information is'nt available in the textbook and I cannot memorize any fact without a supporting ...
4
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0answers
168 views

How is Melatonin Synthesised?

I should like to know roughly how the hormone melotonin is synthetically made for the pharmaceutical industry (i.e. not how it is made in living beings). I can't seem to find any reference to its ...
2
votes
1answer
86 views

Should binding constants be unitless when deriving fractional occupancy equations from reactions?

It is known that binding (aka association) constants are in fact unitless, as has been discussed here already. However, I'm not a chemist and am confused about when one should or should not use units ...
2
votes
1answer
41 views

Number of collisions of particles in a box (or a sphere)

Imagine you randomly spread in a cubic space of volume $m^3$ (or in a sphere of volume $V_s$, as you prefer), $n_A$ particles $A$ and $n_B$ particles $B$. Particles $A$ are spheres of volume $V_A$ and ...
3
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0answers
70 views

How much hydrolysis will likely occur of the following bonds at pH 1-4 in the time period of 1-3 hours?

The bonds are: (I have given pictures of what I mean in case there's any ambiguity that I leave open in these questions. Also so that if you want to number the R groups you've got a head-start) ...
15
votes
2answers
2k views

Xenon and the human body

Reading this article on Wikipedia: Xenon Medical applications I see that Xenon can be used as an anesthetic, neuroprotectant and doping agent. If it is a noble gas, and thus, chemically stable, how ...
3
votes
1answer
51 views

Carcinogens, how do they work?

The easiest carcinogenic thing for me to grasp is radiation, as it directly messes with DNA. Then it seems there are other compounds that simply mimic hormones, but these shouldn't necessarily cause ...
0
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1answer
812 views

How to convert glucose to fructose

How to convert glucose to fructose? Moreover, can there be direct conversion(not necessarily in a single step), or we have to use indirect means, such as from sucrose, or other higher carbohydrates, ...
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1answer
192 views

Thermodynamic vs. Kinetic products

With regards to complexes, I read that thermodynamic products are favored over kinetic products, which are labile. Why wouldn't the first product formed be the most prominent?
3
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2answers
203 views

Photosynthesis, science fair

So I was thinking about something to do for a science fair and photosynthesis sounded like a good idea. I was wondering what the exact process of photosynthesis was on a chemical level. I know the ...