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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Why is ATP the main nucleoside triphosphate used to exchange energy? [duplicate]

Out of all of the nucleoside triphosphates what makes ATP the most used? Is it its structure? The amount of energy it contains? Why is GTP not used as much? What is the deal with the other nucleoside ...
0
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2answers
59 views

Why is water a polar molecule? [closed]

Also, what is the definition of polar in this case? (9th Grade) Does it have to do with the bonds it makes?
0
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1answer
39 views

Immunomic Microarray

"One can measure two or more signals simultaneously determined by a single feature, i.e., epitope in immunomic microarray DNA microarrays measure one response value for each gene per sample; that ...
9
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1answer
217 views

Why doesn't HDL cause diseases like LDL?

LDL particles pose a risk for cardiovascular disease when they invade the endothelium and become oxidized, since the oxidized forms are more easily retained by the proteoglycans. A complex set of ...
1
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1answer
53 views

Why is leucine amino acid used the most in proteins and tryptophan the least?

The amino acid leucine, is used in proteins more than others. Leucine with 9.1 percent (its average in more than 1.150 different proteins) is used most and tryptophan with 1.4 percent is used less ...
5
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1answer
40 views

Are there ways to speed up the growth of plants?

I'm interested in what humans can do to speed up the rate of growth in a plant. I'm interested in both the context of home gardening and large-scale, institution-backed projects. Obviously, optimal ...
0
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1answer
30 views

How is oxygen and carbon dioxide exchange mediated by hemoglobin? [closed]

Oxygen is transferred by hemoglobin from the lungs to tissues, while carbon dioxide is transferred by hemoglobin from tissues to lungs. How is this regulated bidirectional transfer mediated?
4
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1answer
106 views

When should endocytosis inhibitors be used in cell binding assays?

I'm beginning to do some cell-binding assays and I would like for my proteins to not be endocytosed by my mammalian cells. Typical suggestions are for the cells to be kept on ice and that the binding ...
10
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3answers
168 views

Formation of Life

Originally, life evolved from non-living matter. Why is life only generated from other life nowadays, and why doesn't it evolve from inanimate matter, like it did originally billions of years ago, ...
2
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1answer
34 views

What is the importance of urea in mass spectrometry?

What is the importance of urea in mass spectrometry? We use 8M urea to FASP our proteins prior to mass spectrometry. What is the significance of using 8M urea? and how does it affect the proteins?
4
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4answers
186 views

Specificity of Protein Kinases in Signaling Pathways..?

In most of the signaling pathways the activated receptor when activates Protein Kinase through the action of secondary messenger, then these protein kinases almost always phosphorylate on the specific ...
1
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1answer
19 views

What controls Fructose regulation in plants?

Sugars are found ubiquitously in plants and are regulated. For sucrose it's pretty straightforward - it's basically kept at a low ish level, and put into storage or other intermediate compounds. ...
0
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0answers
32 views

How to measure concentrations of different metals from the environment?

Suppose that different kind of metals and chemicals (e.g. magnesium, sodium, copper) got transmitted to environment e.g. as a cause of an accident. How would measure the levels of those metals and ...
0
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1answer
40 views

Taste of salt water

I had a question relating to chemistry and biology, so please tell me if this is suited better for the Chemistry website. My question was, if water dissolves salt by separating the two ions, the Na+ ...
3
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1answer
74 views

How do CO₂ and carbonic acid (H₂CO₃) work in buffering the blood?

Been struggling with this for the past few days even after reading half of the acid base tutorial here, if someone could help me that'd be great. What I don't understand is how HCO3- is supposed to ...
1
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2answers
126 views

Can excessive carbonated drink consumption lead to elevated red blood cell levels?

I've recently had a blood test and the results displayed elevated levels of erythrocytes as well as hemoglobin. (As a result my hematocrit levels were also above average) At my workplace there is a ...
2
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1answer
18 views

Relative sweetness

I have noticed that when I eat something sweet, then afterwards, I eat something else that is sweet, the second sweet food is not as sweet as it usually is. I am pretty sure many others have a similar ...
4
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1answer
99 views

Besides hemoglobin, what proteins are present in red blood cells?

I knew that mature red blood cells (RBCs) lacked nuclei, but I wasn't aware until just now that they also lacked ribosomes and mitochondria. Most cells in the human body all contain a common laundry ...
4
votes
1answer
102 views

What is the physiological difference between cortisone and cortisol?

There is only hydrogen bond different. Cortisol is synthesized by our body, while cortisone is given to the patient. Why you cannot give cortisol directly to the patient? I think the reason is ...
1
vote
1answer
50 views

How does salinity affect the bonds of an enzyme?

According to my textbook, "Too much or too little salt can interfere with the hydrogen bonds that hold an enzyme in its three-dimensional shape". I know that NaCl is held together by an ionic bond, ...
2
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1answer
347 views

What can cause the bloating in high protein diet of Whey proteins?

I am thinking what can cause the swelling of gastrointestinal system i.e. bloating after high protein diet of Whey proteins. Liver does breaks those proteins to branched chain amino acids (BCAA), ...
0
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1answer
38 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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0answers
33 views

Can non-carbonated energy drinks boost alcohol intoxication?

I just read news article about banning caffeine in alcohol drinks and about that energy drinks increase the urge to drink alcohol. Energy drinks cause sugar intoxication - answer about it here ...
2
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1answer
37 views

How do catalase and other antioxidants neutralize free radicals?

In learning about how cofactors are essential to proper enzyme function, my textbook mentioned catalase and its relation to the human body. According to my textbook, catalase is similar to hemoglobin ...
6
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1answer
55 views

How does the body “know” how to metabolize foreign substances

As a freshman biochemistry major, I find myself befuddled by our body's ability to perform complex chemical reactions to break down foreign substances. I can see how we would evolve explicit pathways ...
6
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1answer
450 views

How to Design an siRNA Experiment?

I'm going to undertake an siRNA experiment soon, but I have only read about them. I want to address the role an enzyme plays in processing a protein. From what I understand, I will need to pick two ...
6
votes
1answer
204 views

What's the difference between Ki and IC50?

I have just read this post at researchgate: "How to calculate experimental binding free energy from the IC50 value" I am not be very sure about what the difference is between Ki and IC50. Could ...
0
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1answer
26 views

Binding of Multivalent Antibody to mutiple epitopes?

A multivalent antibody molecule such as Immunoglobulin M Immunoglobulin A etc bind to more than one antigens or epitopes but I am confused about that wheather these multivalent antibodies bind to ...
1
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1answer
68 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 ...
4
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1answer
43 views

Do plants have preference for the form of nitrogen as nutrient?

In the nitrogen cycle (ecology), it is usually described that plants can use nitrogen in the form of ammonium (NH4+) and nitrate (NO3-). Do plants prefer one form of nitrogen over the other?
2
votes
1answer
23 views

Can plants directly use sulfuric acid?

In the explanation of the sulfur cycle, it is often said that sulfur moves from the atmosphere to the ground by acid rain in the form of sulfuric acid. Can plants directly use sulfuric acid to ...
7
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1answer
3k views

Why is fructose not glucose the main energy source of sperm?

The seminal fluid contains fructose as the main energy source for the sperm and not glucose. Why is fructose and not glucose the primary energy source for these sperm, since glucose is the ...
2
votes
0answers
33 views

Fatty Acid Synthesis of Fats Longs than 16 C

I understand that the human body when performing Fatty Acid Synthesis can synthesize only until C16 (palmitate). However the ER has desaturases and elongases. I know that desaturases are used to add ...
3
votes
0answers
78 views

Can cats use ketone bodies as only source of energy?

I recall reading that much of the energy a cat produces from its food comes from proteins which I assume would produce energy via being catabolised into amino acids which in turn, if glucogenic, would ...
57
votes
4answers
34k views

Why is uracil used in RNA rather than thymine?

What is the advantage gained by the substitution of thymine with uracil? I have read previously that it is due to thymine being "better protected" and therefore more suited to the storage role of ...
2
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3answers
55 views

Increasing/decreasing signal intensity in Western blotting

So I was in class and my professor was explaining western blotting. It seems as though there's more than one way to increase or decrease the signal intensity. He presented us the challenge to discover ...
2
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0answers
37 views

Glutamine analysis

I use to run a method to analyse all the amino-acids in a food sample. For that I have to hydrololyse the sample and in the last stage of the method I read the amino acids with a ion exchange ...
5
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1answer
53 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 ...
2
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1answer
69 views

Domains in cell membrane

How is movement of proteins and lipids between different domains of cell membrane prevented? Why is the noncytosolic layer not able to do lateral movements between domains but cytosolic layer is able ...
1
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1answer
35 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 ...
1
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1answer
24 views

To understand synthesis of e-NOS and n-NOS with respect to Ca and calmodulin

I found this sentence in my notes interesting E-NOS and n-NOS are Ca-calmodulin dependent ferments. They are synthesized in small concentration as a response to physiological signals which ...
2
votes
1answer
28 views

Does amylolysis occur in vegetables if stored below 0⁰ Celsius?

Assume that we have a plant, e.g. kale, which is prone to amylolysis if not harvested during a frost period. If it is harvested and put in a household freezer, such that it is frozen solid slowly ...
1
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1answer
41 views

Anesthetics, specifically inhaled anesthetics

I have had a look at previous inhaled anesthetics and many of them appear to be fluorocarbons. What could be the mechanism behind fluorine's anesthetic properties? Is it the specific bonding pattern ...
3
votes
1answer
57 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? ...
1
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1answer
496 views

Amino acid characteristics that determine their chemical properties?

What chemical aspect of amino acids results in their having different properties such that the chemical and physical properties of polypeptides vary with both amino acid content and amino acid order? ...
0
votes
1answer
47 views

What is the charge on oligonucleotide 5' pGpGpApCpT 3' at pH 7.00?

What is the charge on the nucleotide 5'pGpGpApCpT 3' @ pH 7.00? I thought adenine has 1 NH group and Guanine has NH and ...
-2
votes
1answer
46 views

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 ...
2
votes
1answer
47 views

How to manage fat-gluten oxidation in celiac disease?

Assume you have been in non-gluten diet 20 years. You built mass 8 mass with substances containing gluten (endogenous gluten stored in fat). Then, celiac disease is diagnosed. You have been 3 ...
0
votes
1answer
25 views

Can the same protein be represented by primary,secondary,tertiary structure? [closed]

As my book says: Protein can be represented by 4 structures. The primary structure represents the main chain and positions of amino acid residues. But actually, protein is not a rod but rather a ...
2
votes
1answer
38 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 ...