1
vote
0answers
18 views

Regarding benign tumors and what 'stops' them

Benign tumors can grow to dangerous size yet are they capable of metastisizing ; if not what stops this? Also with a benign tumor if you call its cells 'near' its edges its tumor 'cell wall' I was ...
0
votes
1answer
51 views

About the plight of Elephants and efforts to conserve them? [on hold]

Poachers are only after the ivory horns right? I read this story from the New York Times ( I think) of saving a Rhinocerous by some Park Rangers and a Vet. ( forgive spelling) ; they tranquilized the ...
0
votes
0answers
24 views

Nystagmus drug FDA approval?

Congenital Nystagmus is an eye focusing disorder. It happens in manuals. Wikipedia lists several treatments on its page. Are any of those FDA approved for human use of that disease. drugs found ...
0
votes
0answers
11 views

are cranial nerves responsible for the fault mechanism [duplicate]

how speech is produce and why people stammer during the speech. What factor is culprite for the fault mechanism? Is it nerves?
0
votes
0answers
22 views

MRI with lots of white matter.

Why might an MRI show a large amount of white matter and a low amount of gray matter yet have a full skull with little shrinkage in an above average intelligence primate?
1
vote
0answers
32 views

How to visualize the ECM?

Specifically, I'd like to look at changes in HA (hyaluronic acid) production. Most often you only see people staining the cell surface or removing cells from culture for fixation and then imaging. ...
5
votes
2answers
32 views

Alternatives to trypsin for cell detachment?

I have ran out of trypsin and need to passage my cells (immortalized chondrocytes, C28/I2) today or tomorrow. I have been out of town and forgot to order more trypsin. I was wondering if there are ...
2
votes
0answers
12 views

Why is gynodioecy common and androdioecy rare?

Gynodioecy is when a population features individuals that produce both male and female gametes and individuals that produce just female gametes. Androdioecy is when a population features individuals ...
4
votes
2answers
66 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 ...
0
votes
0answers
23 views

are nerves culprit for stammering habit [on hold]

i have been stammering from 9 years old till date[18] . I find different resons for stammering according to people. What is science behind it and how it can reduce?
1
vote
2answers
43 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 ...
8
votes
1answer
1k views

How long does the Ebola virus remain infectious on contaminated items or surfaces?

I'm sure there will be variation depending on what the contaminated item or surface is made of - linens, I could imagine, would remain dangerous for longer than a door-knob. But if the items are not ...
2
votes
0answers
11 views

How many cells in apical meristem

How many cells are there in the apical meristematic tissue? Looking at this picture... I would tend to think that there are few hundreds (maybe only a hundred) cells in the meristem tissue. But I ...
0
votes
0answers
30 views

Can Hepatitis be caused by Bacteria?

There are many information about viral hepatitis. But it is interesting for me, can bacteria cause the hepatitis too?
1
vote
1answer
56 views

What are the disadvantages of forbidding flights to and from the African Ebola region?

After looking through the available Stack Exchange sites, this one seems to come closest to the appropriate place to ask... Popular opinion, including my own, is that banning flights to and from the ...
2
votes
1answer
23 views

Does DNA replication in 5' to 3' (leading strand) need RNA primase?

https://www.youtube.com/watch?v=27TxKoFU2Nw In the above video it shows that during DNA replication, the lagging strand require RNA primase to add 3' -OH group for further addition of nucleotides. ...
1
vote
1answer
28 views

What are the risk factors of elevating legs for too regularly and when tired?

I started to to think the pathophysiology of elevating legs high next to the wall too often and when you are tired. I think possible manifestations some damage to valves of the veins (No!) because ...
0
votes
0answers
19 views

How to change color of urine safely? [on hold]

I am trying to find a SAFE way to change the colour of my urine, from what I have read online, Methylene Blue is relatively safe, and will change urine to blue or green. Is it safe? Can I put this in ...
-3
votes
0answers
18 views

Minerals and water transportion in a tree [on hold]

I need to explain how minerals and water are first absorbed and then transported in a tree. Include the factors that affect this.
0
votes
1answer
26 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. ...
0
votes
0answers
14 views

Book-recommendation: Economic Zoology

I need to have a book which covers following topics two may also be fine: (a) Apiculture, sericulture, lac culture, carp culture, pearl culture, prawn culture, vermiculture. (b) Major infectious ...
0
votes
0answers
10 views

When we vomit how are the contents transferred to stomach/esophagus?

For example if a neurotoxin is to be flushed out through vomiting, it will be absorbed into blood and then sent to stomach/gut. Where does this transfer from blood to gut occur?
-1
votes
0answers
27 views

Transport of organics in a tree [on hold]

I need to explain what happens during the transport of organics in a tree in early spring before the leaves are present.
5
votes
2answers
41 views

Problems understanding membrane potential

I understand that membrane potential is the difference of the extracellular and intracellular ionic charges, due to their concentrations. We say that the extracellular space has a charge of 0 and then ...
0
votes
0answers
30 views

Possibility of an Organism that uses light to communicate? [closed]

Suppose such an organism had evolved from using sound like most life we know to use different intensities, wave lengths, and hues of light to communicate. This is assuming that these creatures are as ...
0
votes
0answers
26 views

What is cocoon like insects that do not contain worms doing hanging only on my bedroom ceiling/curtain? [on hold]

I've had dark colored oval shaped insects predominantly hanging from corner of my bedroom ceiling. They seam to be hanging from a small thread and have found the odd one on my curtain. I sealed ...
0
votes
0answers
26 views

How do chromosomes connect? [closed]

There are 23 chromosomes in human cells, 22 of them are autosomes. There is a lot of research that shows how different disorders are linked to deviations in each chromosome's composition. However, ...
1
vote
1answer
27 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) ...
3
votes
1answer
26 views

Exon skipping in mammals

I've heard from several sources that the predominant form of alternative splicing (at least in mammals) is exon skipping. However, my personal evidence is only anecdotal: I've heard it and read it, ...
0
votes
0answers
28 views

Cost of Substitution explained

I've recently come across an article that mentions "Cost of Substitution" and was wondering if someone can give me a real layman's term explanation of what that is. (Edited:) This was in relation to ...
5
votes
0answers
30 views

Why can you not tickle yourself?

It's the age old question, why can't we tickle ourselves? If you rub your fingers along your skin, sure there's sensation but you don't break down into a laughing fit (at least I don't :P), if someone ...
18
votes
1answer
8k views

Where do migratory birds go when it rains?

I was reading a comic from XKCD which inspired me to ask this question: "well, where do they go when it rains?" I know that when it rains you usually don't see any birds flying through the sky. I ...
2
votes
1answer
36 views

What are some of the general characteristics of the DH5 alpha strain?

I can not find some useful sources unfortunately. Please tell me about some important characteristics of DH5 alpha. What makes DH5 alpha suitable for the gene cloning?
7
votes
2answers
775 views

How do I prepare and clone from E. coli DNA?

I'm looking for a protocol to get genomic DNA from an E. coli sample so that I can clone a small portion of it using PCR into a plasmid. (< 500 bp in this case). It seems OWW (Open Wet Ware) ...
10
votes
1answer
776 views

Can I elute my GFP-tagged protein off anti-GFP antibody using a peptide?

I would like to perform a modified co-immunoprecipitation assay using a GFP-tagged protein. We are going to bind the tagged protein to anti-GFP antibody then bind that to protein A/G beads, however ...
19
votes
3answers
389 views

Good source that explains the evolution of single-celled organisms “from scratch”

Are there any books or sites that detail, step-by-step, the evolution of the first single-celled organisms (bacteria, archaea) from a Miller-Urey-like beginning? That is, assumes only amino acids, ...
15
votes
1answer
571 views

Do large animals often evolve into smaller animals?

There are several examples where the largest animals were killed off preferentially due to a major ecological shift: The KT extinction event The Holocene extinction, as well as the major megafauna ...
18
votes
2answers
324 views

Can an adult without genetic lactase persistence still develop a tolerance for dairy foods?

While investigating the rise of adult lactose tolerance, I came across the news that China has been encouraging its citizens to drink more milk, even though most of the Asian population lacks the SNP ...
6
votes
2answers
1k views

What conditions should I use for Gel Red staining?

What are the optimal staining conditions when using Gel Red? So far, since we have started using it, the gels ran in our lab have been of very poor quality. The bands are very blurred and often ...
11
votes
1answer
299 views

Examples of animals that co-opt toxins?

It is known that there are animals that acquire toxins through their diet or through their surroundings. The examples I know of include butterflies stocking up on alkaloids/glycosides while in the ...
11
votes
1answer
916 views

How is Taq polymerase produced?

I've seen Taq polymerase being marketed as either "native" or "recombinant". I understand that the recombinant version is produced by specially modified Escherichia coli strains that have the gene for ...
17
votes
2answers
264 views

How do fairy rings propagate?

It was somewhat new to me that mushrooms usually aren't individual organisms, but are merely the visible bodies of a bunch of fungi living in the soil. I know that mushrooms emit spores to reproduce, ...
16
votes
2answers
5k views

How do the brain and nerves create electrical pulses?

I have heard that information is sent between the brain and peripheral nerves via electrical pulses or signals, but I don't understand how they create them in the first place.
36
votes
4answers
3k views

Life without DNA?

I'm by no means an expert in the field, merely a curious visitor, but I've been thinking about this and Google isn't of much help. Do we know of any lifeforms that don't have the conventional ...
15
votes
2answers
213 views

Why is there now only one Salmonella species?

Once upon a time, I chanced upon an old microbiology book that detailed the rather colorful world of enterobacteria. Salmonella in particular stood out, as it seemed there were a lot of species: typhi ...
18
votes
1answer
242 views

Is there any convincing evidence for the existence of nanobacteria?

The existence of nanometer scale microorganisms has been proposed and used explain several phenomena including morphological structures in a martian meteorite (ALH 84001) and implication in the ...
12
votes
2answers
486 views

What are limiting factors for intron length?

For predicting genes from a sequenced genome, you need to set a maximum intron length. How long can introns get in animals? Is there some limit?
12
votes
3answers
577 views

Human disease and associated phenotype database?

Does anyone know of any good databases that contain symptoms for diseases and other ailments in humans? I've tried working with UMLS, but thats been impossible to work with. I've also tried working ...
21
votes
1answer
3k views

How long do your eyes need to adapt to darkness and reach full contrast?

I heard you should wait some time until your eyes adapt to darkness and are able to see smallest luminosity differences, otherwise you might overlook faint objects in the ocular. Are there any rules ...
13
votes
1answer
1k views

Why does looking at bright light trigger sneezing in some people?

Why does looking at bright light trigger sneezing in some people? Are there any recent studies that have found a cause for this Photic sneeze reflex? The Wikipedia article only references studies ...

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