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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To understand side-effects for nebivolol's beta1 selective pathway in PubChem? [closed]

Assume you have a drug nebivolol. When nebivolol is used as beta1 selective drug, beta2 is mostly for side effects, but this is not clear from PubChem. I do not know any cases where nebivolol is used ...
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1answer
41 views

Clonidine's adrenonergic nature?

I am little confused here. I used the term adrenoagonist and sympatholytic to describe the compound. However, my teacher says that the correct term here is adrenomimetic -term. My understanding of ...
2
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1answer
42 views

Change in synthesis rate of a molecule changes equilibrium concentration

I was reading the topic of 'The concentration of the molecule can be adjusted quickly only if the lifetime of a molecule is short' from Molecular Biology of the Cell by Alberts. At the end of pg-837 ...
2
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1answer
29 views

What initiates primase to add an RNA primer to a DNA strand and what makes it stop?

What initiates primase to add an RNA primer to a DNA strand and what makes it stop adding RNA nucleotides? Is there tags added to the DNA back-bone?
3
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1answer
91 views

What is the mechanism of action of lithium-induced polyuria?

I was reading in my pharmacology textbook on lithium in treating bipolar disorder, and I was curious to know if there was any specific action lithium takes to produce symptoms such as polyuria and ...
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1answer
629 views

What is the exact chemical composition of human body? [duplicate]

I've just watched Breaking Bad Season 01 Episode 03. In that Walter gives the chemical composition of human body. The conversation is as follows Walter White: Let's break it down. Hydrogen. What ...
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18 views

To Study Interactions of two molecules in PubChem

Assume you have two substances Diosminum / Hesperidinum. The former strengthens vascular walls. The latter has role in some glycoside biosynthesis. From Biochemistry, I recall that glycodises have ...
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2answers
99 views

Can an organism process H₂O into H₂O₂?

In an answer to a recent question on Worldbuilding, I suggested that an organism convert $H_2O$ into $H_2O_2$. I suggested a few processes that yielded the desired final result ($2H_2O \rightarrow ...
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41 views

Substrate specificities of GPPS, FPPS and GGPPS (isoprenoid biosynthesis enzymes)

I have some questions related to isoprenoid synthesis enzymes. Does Geranylgeranyl pyrophosphate synthase (GGPPS) contribute in Geranyl-Pyrophosphate (GPP), Farnesyl pyrophosphate (FPP) and ...
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69 views

Are fatty acids and glycerol lipids?

As far as I know, lipids are defined as biomolecules which are hydrophobic. Triglycerides are composed of fatty acids and glycerol and are considered lipids but, are fatty acids alone or glycerol ...
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797 views

Book Recommendations: GRE Subject Test In Biochemistry, Cell And Molecular Biology

There are probably a lot of really good answers that may vary significantly in terms of content. I'm looking for a set of books that I can read in preparation for the GRE Subject Test In ...
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1answer
42 views

Can Omega 3 Fatty Acids prevent chest pain in periodic Atrial Fibrillation?

It is debated if omega-3 polyunsaturated fatty acids (N3PUFa) may be effective in preventing AF (atrial fibrillation), meta-analysis here. However, much less has been considered this: Do N3-PUFAs ...
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1answer
115 views

Basic question about multiplex PCR

Let's say I have a DNA sequence with the following structure: $$ 5' - N_n - S_1 - N_{1000} - S_2 - N_{1000} - S_3 - N_n - 3' $$ Here, the $N$s represent stretches of arbitrary sequence of the ...
26
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1answer
1k views

Ripening bananas artificially: What is the biological reason

I am a resident of the tropical island of Sri Lanka, and we have a strange traditional method to ripen our bananas quickly. What we do is this: We dig a pit in earth that is enough to put the whole ...
3
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2answers
433 views

Is there a difference between polarity and hydrophobicity?

From literature the two terms seem to be interchangeable when discussing protein domains and motifs. But biochemically, what are the specific differences between these two terms? For example what is ...
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1answer
65 views

Examples of genes involved in plastic responses

Adaptive plasticity involves sensing the environment and responding adaptively to it. Intuitively, I would think that this process may ask for a more or less complex genetic machinery of regulation of ...
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2answers
68 views

Tracking of oxygen molecules in glucose oxidation

For this reaction, found in typical biochemistry textbook: $C_6H_{12}O_6 + 6O_2 \to 6CO_2 + 6H_2O$ I am interested in where do the oxygen atoms of $6O_2$ go. I think they go to $6H_2O$, but this is ...
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1answer
33 views

Phospholipid movement in cell membranes

What causes phospholipids to flow so quickly in cell membranes? In Biology by Cambell et al. they state that a phospholipids can travel up to 2 micrometers per second. Is that a random movement or has ...
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2answers
397 views

Why would an Eadie-Hofstee Plot be non-linear? [closed]

Besides cooperativity between multiple active sites on an enzyme, what are the other reasons for the Eadie-Hofstee plot to be non-linear?
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1answer
75 views

How do the quantities of ATP formed during aerobic and anaerobic respiration compare? [closed]

How do the quantities of ATP formed during aerobic and anaerobic respiration compare?
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1answer
102 views

Identify the pink mold infecting refrigerated lemons [closed]

I made lemon juice 6 month ago. I just washed the lemon using brush and then cut them into pieces. Then I put one layer of lemon in the bottle followed by one layer of sugar Again one layer of lemon ...
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1answer
35 views

What are the reactions in the body that triggers dizziness after cigar(nicotine) smoking in non-smokers?

Suppose there is a person that has never used nicotine in any form in his/her life. Why does the person get dizzy after a few "shots" from a cigar(nicotine)? What's the difference between using other ...
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1answer
18 views

What enables azacitidine to incorporate into both DNA and RNA?

I did a mini-project on the drug azacitidine for my pharmacology class, and I learned that azacitidine has the ability to incorporate into both DNA and RNA. I think this is really unique because a ...
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288 views

HIV and effectiveness of inhibitor cocktail over single inhibitor

I'm looking for clarification on the answer to this question. It's in my biochemistry class but I figured this is more Biology than Chemistry, so I'm asking it here. The question is: One of the ...
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1answer
160 views

Is the activity of enzymes in the human body affected by the outer temperature?

I have to do a research about the enzymes in the human body and the things that affect them. I know that the body temperature affects the activity of enzyemes but I'd like to know if the outer ...
2
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1answer
28 views

Help me understand my membrane potential assignment

Epithelial with the ability to transport NaCl is bathed in an isotonic salt solution with these values (in mM): 136 Na, 6 K, 140 Cl. The intracellular concentrations are: 45 Na, 100 K, 13 Cl. The ...
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3answers
889 views

How does protein denaturation work?

I was wondering how protein denaturation works. Are there covalent bonds, such as disulfide bridges involved, or is it based purely on non-covalent bonds such as hydrogen bonds? Why is denaturation ...
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2answers
73 views

How does high-fidelity of DNA replication depend on the formation of hydrogen bonds?

Replication has an error rate of less than 1 in 100 million. DNA polymerase forms H-bond with the H-bond acceptor atoms in the minor groove. <-- enhance fidelity here? Binding of the triphosphate ...
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1answer
57 views

Book-recommendation: Biochemistry

I need to have a book which covers following topics two may also be fine: (a) Structure and role of carbohydrates, fats, fatty acids and cholesterol, proteins and amino-acids, nucleic acids. ...
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1answer
82 views

Understanding intra and extracelullar concentrations (membrane potential)

I have 4 question (not homework) What happens to the cells membrane potential if: a) Na+ outside rises by 40mM b) K+ inside rises by 10mM c) K+ outside rises by 10mM d) A- (impermeable ion) ...
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2answers
116 views

Is there a known glucosepane cross-link breaker?

I read the following on wikipedia: There is, however, no agent known that can break down the most common AGE, glucosepane, which appears 10 to 1,000 times more common in human tissue than any ...
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1answer
77 views

Why is the ebola virus so intense now?

So i'm looking into the ebola crisis and it seems the death toll is really getting crazy. I understand that it's a cytomegalovirus and that it basically overwhelms the immune system due to it's size ...
2
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1answer
46 views

Why is coconut oil healthier when it has so much saturated fat?

I noticed that coconut oil has ~96% saturated fat, and I was under the assumption that saturated fats = bad for health. Why is it that coconut oil is healthier to alternatives with much less ...
2
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1answer
221 views

What is the result of meiosis?

Is the result of meiosis ONLY the sex gametes (male and female) which later meet to form a somatic cell? Sometimes I feel as if my book is hinting towards meiosis is the process where sperm cells meet ...
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1answer
104 views

Preservation of human tissue

At my med school we have human samples (body parts, organs, etc.) They are soaked in some sort of solution for long term storage. I'm quite sure that it's not formaldehyde as that would be really ...
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1answer
129 views

Formaldehyde turns plantar region of feet red?

I'm a freshman med student and I've noticed that on all the feet (and hands) of deceased people that I've worked with, the bottom of the feet always turns red and also the inside of the palm? Why is ...
4
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2answers
464 views

Are there any multicellular forms of life which exist without consuming other forms of life in some manner?

The title is the question. If additional specificity is needed I will add clarification here. Are there any multicellular forms of life which exist without requiring the consumption (destruction) of ...
3
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1answer
529 views

NADH inhibits gluconeogenesis?

I was told in a physiology lecture that alcohol inhibits gluconeogenesis because 'NADH produced from ethanol catabolism leads to product inhibition'. But is NADH not a reactant coenzyme of ...
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1answer
48 views

All or nothing phenomena

We know that an action potential is produced by an active cell membrane when the stimulus reaches a certain threshold. When it does, an action potential fires, and when it doesn't, nothing happens. ...
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1answer
48 views

How does fluorouracil inhibit pyrimidine synthesis?

I was reading in my pharmacology textbook about fluorouracil, and my book mentioned that fluorouracil is an antimetabolite whose function is to inhibit pyrimidine synthesis. However, I was curious to ...
6
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1answer
217 views

How many RNA-binding proteins can simultaneously bind on a single mRNA?

Typically, how many RNA-binding proteins can simultaneously bind to a single mRNA? Or said differently, how many "binding sites" does an mRNA have? What order of magnitude? I am interested in RNA ...
3
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1answer
73 views

PSI-BLAST website algorithm parameters

http://blast.ncbi.nlm.nih.gov/Blast.cgi In this website, when I want to apply the psi-blast algorithm on a sequence, under the section of algorithm parameters , what does PSI-BLAST threshold mean? ...
4
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1answer
54 views

protein-binding sRNAs

I am actually a computational biologist, pardon me if my question description is a bit off-note, my curiosity is driving me on A bit of background and context: In bacteria, a regulatory protein ...
0
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1answer
44 views

Epitope annotated protein

What is epitope annotted protein?? The book from which I got this term is : http://www.springer.com/biomed/immunology/book/978-1-4939-1114-1
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0answers
21 views

Sequence based method for prediction of continuous B cell epitope

What is Sequence based method for prediction of continuous B cell epitope? What is the algorithm/procedure of this method? Can someone please explain this to me in simple language?
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1answer
70 views

5,6-dihydrouracil and 5,6-dihydroxyuracil - how they arise in DNA?

5,6-dihydrouracil can be formed from cytosine after exposure of DNA to ionizing radiation under anoxic conditions [Ref]. What are other ways by which 5,6-dihydrouracil is formed in DNA? What about ...
2
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1answer
20 views

Are the cpli and ctli tests time senstive(i.e. is it needed to test right away in order to get accurate results)?

I'm sending the blood samples to a lab and this takes some time until the actual testing. Some information on the tests. TLI : ...
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64 views

Are triglycerides fat?

I have a quick question: Are triglycerides essentially what we call "fats"? I've tried reading up on it but there seems to be some conflicting information. Thank you.
2
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1answer
317 views

What are the ways to test for protein in the canine urine?

I know that one way is to use the reagent sticks and the refractometer, but this is inaccurate. Is protein distinguishable when using a microscope? Is it time sensitive(i.e. have to test it right ...
6
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1answer
82 views

Where do the electrons and protons formed from biological reactions go?

In a reaction like disulphide bond formation protons and electrons are released. These particles are presumably damaging in high levels. What systems are in place to prevent a build up of electrons ...