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Questions tagged [biochemistry]

The study of chemistry within the scope of biology: the compounds that occur and the reactions involving them in living organisms.

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Where different types of proteins can be found in food?

According to https://www.youtube.com/watch?v=KSKPgaSGSYA (created by one of the largest supermarket chains in the UK), different proteins have different roles in human body: (Group 1) They’re like ...
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24 views

How to relate different phospholipid structures with entropy?

Phospholipids can form different stuructures like micelles, liposomes and bilayer. How can I relate this with entropy? ie explain different these different shapes based on entropy knowledge.
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8 views

Using different polysaccharides for coagulation [duplicate]

Would a particular type of polysaccharide be better at coagulation than another? For example, would the presence of cellulose in a bio-coagulant be more effective at coagulation than the presence of ...
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12 views

How do polysaccharides help in coagulation? [duplicate]

Why are bio-coagulants with high concentrations of polysaccharides (i.e. starch and cellulose) effective at reducing the turbidity of contaminated water? Alternatively, why would bio-coagulants with ...
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What happens to lipoprotein lipase after a sugar only diet?

Insulin increases the activity of lipoprotein lipase thay allows cells to take in lipids from chylomicrons in the blood. If a person takes a sugar only meal like drinking coke, insulin is released. ...
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92 views

Is starch a better coagulant than cellulose?

In an experiment, I used plantain peels (with a very high starch content and very little cellulose) and grapefruit peels (with a very high cellulose content and no starch) as coagulants (ensuring that ...
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4answers
1k views

What is the difference between a protein and a factor?

In terms of nomenclature/semantics, why are some proteins named proteins, and some named factors? I've been revising on eukaryotic DNA, and I've come across some proteins that seem to serve roughly ...
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57 views

Can we investigate the cell biology of extinct microorganisms?

I know that there are microfossils, but not if we can we know about the organelles, genetics or macromolecules of the cells that left them behind.
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1answer
53 views

How is mankind important to nature? [closed]

Like mosquito eggs are important for fish, what’s our role in balancing the life on earth or its ecosystem. Please suggest if this question doesn't fit in this community. I am a mechanical engineer ...
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1answer
64 views

HELP! What does pH of 14 look like? [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 ...
2
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1answer
49 views

In the induced fit model for enzyme action, does the enzyme active site change slightly after products form? [closed]

The reason why I am asking is because I am looking at a past paper and they highlight that it does. I have attached it below. Could you explain why this is the case. I am just looking for a quick ...
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2answers
331 views

What is C-terminal tryptic peptide?

A biologist wrote to me: ... C- or N-terminus,... For example, a C-terminal tryptic peptide like AGWRGSDSHSR, would be... I don't have any idea what that is. When ...
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1answer
208 views

To what extent is prion aggregation responsible for Alzheimer's disease?

I was intrigued by a description of prions as a factor regarding 'Mad Cow Disease', the epizootic threatening the cattle stock of the United Kingdom and France predominantly. Understandably, the ...
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2answers
87 views

Why are my calculations for O2 requirements of daily metabolism so far off?

When I attempt to calculate the O2 necessary for a day of metabolism at rest (for an imaginary average human) and compare it with the expected O2 consumed per day my results differ by a factor of 3. I ...
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1answer
35 views

Nonpancreatic digestion of tryglicerides

In an answer about coconut oil I can read the digestion of coconut oil does not involve in the Pancreatic digestive enzyme system In both primary and secondary school I have learned that fat needs ...
0
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1answer
24 views

Is it possible to induce protein activation via frequency-specific mechanical waves? [closed]

Would it be possible to induce shape changes in specific proteins by providing specific frequencies of mechanical waves in a thermostatically controlled environment such that those proteins may be ...
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0answers
154 views

Effect of Testesteron and Estrogen on adult opposite sex?

I know that if Estrogen is given to a teenage male then it triggers the development of secondary sexual characters of a female the male body, like breast growth and other. and similar happens if ...
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1answer
10k views

What would cause a single white eyelash?

I couldn't find a paper who could give me the explanation. Unfortunately, according to my search, it seems there are not many reported case, particularly for the younger population (<30). Would ...
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1answer
69 views

The threshold of Ki

Is there any threshold (Ki) between strong and week small molecule inhibitors? When I see the (Ki) values in any published work, how can I decide if this good or bad inhibitor?
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0answers
54 views

Measurement equation of Tree-Step pathway model

I am not specialist in biology but I want to test a parameters estimation method (based on Kalman filter) on the Tree-Step pathway model, but I cannot find a document that gives the measurement ...
4
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1answer
112 views

How is a very small quantity of poison able to kill a large organism?

Take cyanide for example: it prevents mitochondria from producing energy in form of ATP but, in the process, it binds with it and hence it's spent. It's theorized that half a gram of cyanide can ...
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0answers
44 views

how do I work out the fraction as a percentage of the ADP in each mitochondrion converted into ATP?

So I was given the following concentrations ADP=1.3mM and ATP=4.8mM, and work out from this that in a given set of dimensions (2micrometers long and 1 micrometer in diameter) that there were 1....
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4answers
97 views

Why does DNA mutate?

I just read that pregnancy in space would be super dangerous because - among other reasons - of a higher risk of mutations due to radiation. This made me wonder: why does the DNA in organisms mutate? ...
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What is the difference between GFP and rhodopsin?

GFP and Rhodopsin are both fluorescent proteins. What is the main difference between GFP and Rhodopsin in terms of how they work? I know that their excitation and emission wavelengths are different, ...
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1answer
42 views

what is the active ingredient in cymbopogon citratus that repels mosquitoes?

We are doing a project about mosquito repellants using lemongrass, cymbopogon citratus. But, based on our researches online, it stated that it was all a hoax and a better alternative is its cousin ...
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16 views

Why does egg white grow watery?

I have read that the white of an egg becomes watery as it ages. What is the biological and biochemical mechanism of this transformation?
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0answers
38 views

Sucrose inhibit onion root mitosis? Why?

I am doing an experiment about onion root growing. I had put an onion in different solutions of $C_{11} H_{22} O_1$ in H2O —with the root touching the water—: 0,1M; 0,2M; 0,3M; 0,4M; 0,5M. The ...
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1answer
53 views

How do you culture Cutibacterium acnes?

I've been thinking of culturing Cutibacterium acnes (old name is Propionibacterium acnes) for a thesis topic of mine on the comparison of the efficacy of local antibacterial topical skin care products ...
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2answers
2k views

Was iron important for the first life on Earth?

Some ions or compounds are thought not to have become involved or important in the metabolism of living organisms until some time after certain mutations took place. For instance, early life is ...
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0answers
17 views

Healthy dog's salivary composition vs. A dog with rabies

I was wondering if there are any difference in the salivary composition of a healthy dog's saliva to that a dog with rabies.
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0answers
168 views

Transaldolase vs Transketolase

What is the difference between transaldolase and transketolase in the pentose phosphate pathway? From what i understand, they both catalyze the transfer of carbon chains from 1 aldose into 1 ketose to ...
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1answer
65 views

why is LPL (lipoprotein-lipase) down-regulated during fasting?

During fasting our body needs additional sources of energy and that's why triglycerides are broken down into fatty acids and glycerol. where fatty acids can be used to generate acetyl-coA and ...
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0answers
45 views

Comparison between banana and human dopa oxidase

Dopa oxidase - an enzyme which catalyses the conversion of L-dopa to dopachrome - can be extracted from bananas but is also present in the mamilliam brain as a precursor to a number of ...
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0answers
19 views

What is the chemical mechanism by which PcP(c) is converted to PcP(Sc) in Fatal Familial Insomnia

I know the gene PRNP and it's location. There’s a mutation at codon 178 (asparagine found instead of normal aspartic acid) on the prion protein gene (also found in fCJD) and more uniquely there is a ...
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1answer
60 views

Biochemistry Question: Antibodies

I'm doing conceptual questions in preparation for a Western Blott and needed clarification on a specific question: Is it possible/ will your Western blot work if you use a primary antibody (say ...
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0answers
12 views

What are the final concentration of ions intracellularly and extracellularly after equilibrium potential is reached [duplicate]

Background Suppose there is a neuron whose initial intercellular K+ concentration is 400 mM and the extracellular K+ concentration is 20 mM. And the neuronal membrane is permeable only to K+. I have ...
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0answers
25 views

Quantification of concentration from chromatogram paper [closed]

In an experiment, I recently isolated and purified calf thymus DNA, hydrolyzed it with perchloric acid, and then applied the hydrolyzate to a Whatman paper in a polar solvent and let it run overnight. ...
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72 views

Would I expect salt precipitate on fibres of DNA in a NaCl water solution?

I just recently conducted an experiment in my biochemistry class where we had to add DNA to distilled water, isotonic saline and 2.5M NaCl. I noticed different physical aspects depending on the ...
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1answer
787 views

Why are fatty acids consisting of even number of carbons predominant?

Most of the fatty acids in animal biology consist of even number of carbons in its parent chain. What property of such fatty acids cause the biological systems to prefer them over the odd counterparts?...
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1answer
277 views

Which statement is incorrect for Rubisco?

My question is this: Which of the following is NOT correct for rubisco? a. It is the most abundant enzyme b. It catalyzes two different reactions c. It is involved in photorespiration d. It is not ...
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1answer
65 views

Blackgram leaves. SDS page. Phosphate buffer method

I am doing protein analysis in blackgram leaves by using phosphate buffer method. But I cannot get proper bands on my SDS-PAGE. What should I do to get proper bands?
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744 views

Non-Competitive Inhibition vs Allosteric Inhibition

The Vmax of a reaction is lowered in presence of a non-competitive inhibitor (compared to the control - without a inhibitor) However, (Vmax of the reaction stays the same in presence of an allosteric ...
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0answers
15 views

What is the concentration/molecules per cell of iodothyronine deiodinase in a cell?

I'm trying to parameterize an in silico model and need the approximate concentration (M), or molecules per cell, of iodothyronine deiodinase type II (D2) enzyme in a human cell, ideally a glial cell. ...
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3answers
5k views

Can plants suffer from CO2 poisoning?

Is there a point where too much CO2 is bad for a plant? Basically when there is too much CO2 in the air can a plant get sick? Since plants photosynthesize and need CO2 to generate glucose and store ...
3
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1answer
67 views

Do tRNAs that recognize multiple codons have any preference for one over another?

What are the effects of the different binding strength/affinity between the synonymous codons corresponding to a single tRNA ?
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1answer
175 views

Laemmli-SDS-PAGE problems [closed]

I did Laemmli-SDS-PAGE for my Ammonium sulphate precipitate but I had very weak band and have very weird part at the end of gel. Please help me to solve that problem. Thanks
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0answers
13 views

Adenosine receptor affinity states

Adenosine receptors have two different affinity states. Can an antagonist action like 1,3,7-Trimethylxanthine change the affinity state as a fast form of adaption, before new adenosine receptors are ...
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0answers
18 views

What is a good biochemistry reference for reading papers about metabolic pathways associated with human disease?

I studied first and second year biology at university about 15 years ago, taking courses in cell biology, comparative physiology, microbiology, and human cell biology. I also took the supporting ...
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1answer
235 views

How is the gradient in density gradient centrifugation made?

From the literature I read, I came to understand the following. Please correct me if wrong. In CsCl gradient centrifugation, the gradient is achieved by centrifuging the CsCl solution at high rpm, ...
2
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1answer
850 views

What is the structural difference between beta and gamma globin chains of Hb?

Hemoglobins are tetramers composed of pairs of two different polypeptide subunits. The subunit composition of the principal hemoglobins are α2β2 (HbA; normal adult hemoglobin), α2γ2 (HbF; fetal ...