1
vote
1answer
79 views

interpreting enhancer and promoter regions of a target gene

I am reading a paper which talks about promoter/enhancer regions of certain protein coding genes. These genes are for which evidence points to having strong MEF2 transcription factor binding sites. ...
1
vote
0answers
26 views

how food moves in horizontal coils of small intestines [duplicate]

This is a very very basic question, and I am looking at it more from point of view of physics. The small intestine is a highly coiled structure, which means it has horizontal coils as well. I can ...
1
vote
0answers
10 views

Plants and animals ability to survive polypoidy conditions [duplicate]

In mammals the condition polyploidy produce something euphemistically termed "general developmental disruption" ,practically speaking this means system meltdown which happens very quickly. There is ...
3
votes
0answers
42 views

Protein-Bound Drugs in Kwashiorkor

Kwashiorkor is characterised by decreased serum protein (including serum albumin) due to poor dietary protein intake. What is the effect of this lowered serum protein on highly-protein-bound drugs? ...
0
votes
1answer
188 views

if the load is removed from an eccentrically contracting muscle, will it start contracting concentrically?

Geometrically speaking, a muscle contraction should exert a force between the two attachment sites. However, the actual effect of the force on the overall geometry of the body near the point of ...
16
votes
3answers
2k views

Are there cats with black skin?

Some mammals can have a black, pink or spotted skin, depending on race - see for example humans or pigs. But I recently learned that this is not the case with mice. Even black furred mice have pink ...
2
votes
1answer
901 views

How are 23 chromosomes in human sperm chosen?

I'm not biologist and I have just a basic knowledge. I've been thinking for a long time about the following question: How does the body choose which 23 chromosomes should be active in human sperm and ...
3
votes
2answers
121 views

Biochemical coupling between two enzymatic reactions - Enzymes physically associated?

I am wondering what the exact definition of biochemical coupling between two enzymatic reactions is. I know that these two enzymatic reactions have to share the same intermediate(s) one is ...
3
votes
1answer
139 views

How can TMS induce enough depolarization to cause an action potential?

Creating an action potential needs at least tens of mV potential difference across the membrane to occur. But the membrane is really thin, surely less then 0.01µm (some reference give 25A). Then the ...
4
votes
1answer
82 views

What (open) software there are for simulating behaviour of human (cortical) neurons?

Is there any reliable open-source software for simulating the behaviour of human cortical neurons? I am looking for serious software, so let's assume I have access to a computer with more than 10,000 ...
1
vote
0answers
73 views

How do I use BEAST for divergence time estimation in this case?

I am interested in using BEAST to find the divergence time estimates of species separations within a genus of frogs. The genus separated from a outgroup taxon I have chosen around 80 million years ago....
3
votes
1answer
75 views

Survival of streptococcus after my scarlet fever

I'm currently sick because of scarlet fever but I got treated with antibiotics. I know that after 1.5 day using antibiotics the streptococci I release at home are dangerous anymore. But my question is,...
1
vote
0answers
164 views

What is the chemical makeup of mealworm frass?

We have been raising mealworms for some time and while mealworm frass has proven very useful as a plant fertilizer, I started wondering about other potential uses of this leftover waste. Can someone ...
2
votes
0answers
178 views

White/Gold vs Blue/Black dress

So I'm sure you've all seen the dress photo where people see the dress as either White and Gold or Blue and Black. It has essentially 'split' the internet because some people see the dress and they ...
1
vote
1answer
163 views

What is the role of Aspartate Transaminase in gluconeogenesis?

I know that oxaloacetate cannot cross the mitochondrial membrane, but can instead be converted to aspartate, shuttled out, and then re-converted back to oxaloacetate. What does this have to do with ...
1
vote
0answers
109 views

Common properties of herbs in creating anaphrodisiac effect?

Recently came across Wiki article about anaphrodisiac herbs and other products. An anaphrodisiac (also antaphrodisiac or antiaphrodisiac) is something that quells or blunts the libido. It is the ...
4
votes
0answers
38 views

Procedure for doing western blot [closed]

I am writing a step by step guide for doing a western blot for a class. It is intended for any one with basic Biology lab skills. I am hoping people will review my draft and give feedback on how to ...
1
vote
1answer
73 views

What are pseudoknots?

I'm trying to get my head around what a pseudoknot is and how I can identify them given some RNA string. For example, suppose I have a string s = CGUUGUGUACACGAUAGUACAU. Suppose the two longest ...
8
votes
1answer
611 views

Are bacteria necessary for an individual's life, or, how long could a person live without bacteria? [closed]

Bacteria are essential to life in that they are responsible for breakdown of organic substances, etc. but are bacteria necessary for an individual's life? In other words, how long would a human ...
0
votes
1answer
681 views

What is the role pyruvate carboxylase in lipogenesis?

I just know that Acetyl-CoA is a positive allosteric modulator for pyruvate carboxylase, but I cannot find anything else.
3
votes
1answer
228 views

How do genetic chimeras with different blood types not die?

If a person is a chimera and has two different blood types in his veins, how does he not die? Shouldn't the immune system attack one of the blood types? In 1953 a human chimera was reported in the ...
2
votes
1answer
60 views

Detailed mechanism of the cause of diabetes mellitus type 1?

I have read in some texts that diabetes mellitus type 1 is caused by degeneration of beta cells due to our body's own immune reaction.Is it true? Can you explain further how are such types of immune ...
5
votes
1answer
416 views

To which negatively charged components of the cell envelopes do the crystal violet complexes bind in gram staining?

The gram positive have negative components in the peptidoglycan layer in the form of teichoic acid phosphodiester bonds, and the gram negative have negative components in their outer membrane in the ...
2
votes
1answer
67 views

The human organism knows what we have to eat? [closed]

My mother has told that if your organism needs a vitamin, you want fruits include that vitamin. For example you have lack of C-vitamin you would like to eat lemon. Is there any explanation for it, or ...
5
votes
1answer
173 views

Strange Cordeyceps-looking Mushroom in Australia

In the past few weeks, after the rain started up I noticed these mushrooms around my local area. I'd never seen them previously out of the 20 years I've lived here (a town in Queensland, Australia). ...
1
vote
1answer
70 views

Which organisms have their cell wall made of polysaccharides and amino acids?

I came across a question which somewhat goes like In which of the following kingdom, most of the members have a cell wall made of polysaccharide and amino acids ? - Monera or Fungi. To me it ...
2
votes
0answers
43 views

why plants cannot use atmospheric nitrogen? [duplicate]

Earth's atmosphere constitutes 78% of Nitrogen, then why do plants need to absorb Nitrogen from the soil. Why couldn't it possible for them to absorb the atmospheric Nitrogen like they do in the case ...
3
votes
1answer
136 views

What's the (or some of the) minimum(s) amount of atmospheric carbon dioxide needed by plants?

We currently have a problem of increasing CO2 in the atmosphere. But assuming we find a way to carbon sink it, what is the minimum CO2 we need to leave in the atmosphere to provide a source for ...
2
votes
0answers
37 views

Are there anyother method under research for curing rabies? [duplicate]

Why is rabies incurable after onset of symptoms? Although we administer HRIG (lyssa virus antibody) to the patient, why doesn't it work after onset of symptoms? And are there any other successful ...
2
votes
0answers
41 views

Link between macro lncRNA and DNA looping

I was wondering if anybody knows some publication about macro lncRNA (very long unspliced RNAs) or more generally a transcribed RNA that may lead to cis-DNA looping of genomic regions overlapped by ...
2
votes
0answers
22 views

protein with highest affinity to lactose

I was wondering: What is the protein with the highest affinity to lactose ? Are there some databases with values for affinity ? Thanks in advance
2
votes
1answer
439 views

What is the difference between gene and CDS annotations?

I have a bunch of sequence files fetched from the EBI ENA and I'm trying to find the end of the 5' UTR for specific genes. The UTR itself doesn't seem to be annotated in most sequence files I have. ...
0
votes
0answers
98 views

With humans, is being transgender innate, or caused by social factors?

In humans, is being transgender something that is innate, or is it caused (or made more likely) by social factors such as their political beliefs, their religious views or their social environment?
5
votes
1answer
6k views

Why does high pH result in the denaturation of DNA?

In the Southern blot method, for example, a solution of NaOH is used to denature the DNA in the sample. I find this counterintuitive since I expected that $\text{Na}^+$ cations would neutralize the ...
1
vote
0answers
166 views

Baby birds hair and mammal hair is a convergent evolution?

Chicks (baby of chickens) and ducklings seem to have fine hairs, at least something look like hairs to me. Most mammals have hairs, but reptiles, fish, or other animal groups do not have hairs as far ...
1
vote
1answer
70 views

Using a Sphygmomanometer [closed]

If you were to use an older sphygmomanometer and a stethoscope to record blood pressure, why would you hear no sound when the cuff was inflated to 160mmHg
6
votes
1answer
701 views

Why do most organisms have negative supercoiled DNA?

It has been observed that in nature most organisms have negative supercoiled DNA and that few organisms have positive supercoiled DNA. Some of the organisms that have the positive supercoiled DNA live ...
1
vote
1answer
223 views

Examples of how the presence or absence 2'-hydroxyl groups influence physicochemical properties of DNA and RNA

I know, for instance, that RNA is much more succetible to alkaline hydrolysis than DNA and this difference is determined by the presence of 2'-hydroxyl group in ribose. I have also heard that "DNA is ...
4
votes
2answers
328 views

Relative microRNA comparison from from TCGA data?

I have a conceptual question that I was hoping someone could answer. Can I say that microRNA A is expressed x-fold greater than microRNA B directly from the TCGA miRseq data? Can I do this after ...
2
votes
0answers
160 views

Parasites with both plant and animal hosts?

Are there animals (or plants) that are parasitic on both animals and plants? Especially such that they rely on their plant host being eaten by their animal host?
1
vote
1answer
226 views

How does ANF increase GFR?

ANF as we know reduce the Na+ uptake and K+ removal in the distal tubules and it also functions as a Vasodialator (?) But again it says that ANF increases the Glomerular filtrate ? But if it is acting ...
2
votes
0answers
38 views

What makes substances allergenic?

Is it possible to tell or rule out (potentially a priori) whether any given substance or compound is likely and how likely to cause allergies with high confidence, without the need to conduct ...
2
votes
1answer
104 views

Why are plasmid genes not already incorporated into bacterial chromosomes if necessary for stressful situations?

If plasmids are important for bacteria to express specific genes under stressful conditions, why are these genes not already incorporated into their chromosome to begin with? What is the evolutionary ...
0
votes
1answer
32 views

How did multicellular life evolve? [duplicate]

I can imagine several specialized unicellular beings collaborating. But how does life get from that point to a unique pluricelular being that reproduces into another pluricelular being?
1
vote
0answers
73 views

What are the white spots?

What are these white spots? It's like Braille writing or something. How is the appearance encoded in the plant? (which I think is a Pine, though I am not sure).
9
votes
2answers
68 views

How can bats achieve good resolution with wide beams?

I have been reading about the echolocation system in bats. papers state that bats tend to produce a sonar beam that has a beam angle (-3db) of about 30-40 degrees. This would be considered a wide beam ...
1
vote
0answers
30 views

Why is carbonylation added as a fixed modification in mass spectrometry peptide analysis?

When using mass spectrometry analysis software we use carbonylation as a fixed modification. What is the significance of this modification and why doesn't it change?
3
votes
2answers
1k views

Can cell exist without Ribosomes? [closed]

Last night I came across a question that goes as follows:- Cells cannot exist without a) cell wall b) cell membrane c) mitochondria d) ribosomes I am getting confused with option B and option D ...
0
votes
1answer
254 views

How to select genes before log2 ratio on a RNASeq gene expression matrix, based on signal median

I want to transform a TCGA mRNA expression matrix (in linear data format) to log2-ratios and then run a feature (gene) selection, selecting the 1000 most variant genes (genes with higher standard ...
2
votes
2answers
273 views

Why people fear GMOs? Can't we map a plant composition?

My main question is can we map what a fruit is made of? For instance apples are made of 0.0002% of protein X, 0.00001 of protein Y, 0.001% of amino acid Z... etc... If we can, then my next question ...

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