1
vote
1answer
762 views

What is solid-phase bridge amplification?

During Illumina sequencing there is a step called bridge amplification by which DNA is amplified by isothermal enzymes. What is this stage, and how does it work?
6
votes
2answers
11k views

What's the difference between shotgun sequencing and clone based sequencing?

Whilst I appreciate this is a large topic, what are the main differences between shotgun sequencing and clone based sequencing?
7
votes
1answer
2k views

Does the human ear adapt to noise levels?

I have noticed lately that if I go to sleep, when I have my radio running, it is on lowest volume, I still consider it kind of loud. In the morning, when being on the edge of waking up, I hear the ...
1
vote
1answer
53 views

“Oblong to Allantoids” … Is it valid?

I read on the text book: The characteristic of Dinemasporium are: superficial, cupulate to Discoid conidiomata with brown satae, Phialid conidiogenous cells that give rise to hyaline, oblong to ...
1
vote
1answer
287 views

By what mechanism does elevated homocysteine level accelerate thrombin formation?

It has been stated that elevated homocysteine level accelerates thrombin formation. By what mechanism does this happen?
2
votes
2answers
523 views

By what mechanism does elevated homocysteine level cause endothelial dysfunction and damage?

It has been stated that elevated homocysteine level causes endothelial dysfunction and damage. By what mechanism does this happen? Why is it the endothel where elevated homocysteine causes problems? ...
0
votes
1answer
74 views

Does anyone know what marsupial this is? [closed]

I know what this is a marsupial, but i'm not quite sure which one. Any thoughts?
2
votes
1answer
58 views

How can I view modENCODE data faster?

I am trying to view several data tracks in the modENCODE GBrowse genomic browser. However, the site is so slow, it is practically unworkable. Is there a faster way to explore the data?
5
votes
1answer
525 views

How do sharks and other fish conserve and gain water in marine environments?

With the osmolarity of the average vertebrate being around 300mOsml, and salt water having an osmolarity of 1000mOsml, why does the water from the shark not leave to the salt water around it? I ...
3
votes
1answer
3k views

Is it possible for a person to become “reinfected” with the same strain of a virus?

If a person contracts a virus, viral conjunctivitis for example, is it possible for the individual to become "reinfected" with the exact same strain of the virus once the person has it treated and the ...
1
vote
1answer
60 views

Are there neuronal firing artifacts produced by head movement?

I'm experimenting with a consumer-grade ElectroEncephaloGram (EEG) sensor and have created the image below using the device. Because the sensor on the device does not use a suction cup, there are a ...
2
votes
1answer
120 views

Is RGB diode lighting okay for the eyes?

Is a light source giving off light composed of red, green and blue lights harmful to the eyes? Does it lack any important qualities that other artificial light sources, such incandescent lamps or ...
2
votes
2answers
215 views

Is it possible to print humans?

According to this news, scientists can use stem cells to print objects. So say theoretically, is there any possibility to print human beings?
2
votes
2answers
459 views

DNA replication Okazaki fragments

I understand multiple origin bubbles; DNA polymerase only synthesizes DNA from 5' to 3' and all that. But what I don't understand is why it has to be in fragments. Yes, DNA is anti parallel, and so ...
2
votes
1answer
543 views

Will lipid molecules 'flip-flop' over a membrane without the use of an enzyme?

All of the references to this I can find refer to enzymes like Flippase making it 'easier' or 'more likely' that the translocation will occur, rather than actually make it possible. The following is ...
11
votes
3answers
4k views

What is the evolutionary reason behind the fragility of teeth?

Almost all organs in the human body have a rather large threshold within which the organ or tissue is capable of repairing itself using materials supplied by the body, whether it's made from organic ...
2
votes
1answer
167 views

Why is elevated homocysteine considered a risk factor for angina?

Elevated homocysteine levels are listed among risk factors for angina. How is homocysteine related to the heart? Or the coronary arteries? How do these relationships make it a risk factor for angina? ...
2
votes
2answers
50 views

Can stress echocardiography show coronary blood flow difference before and after exercise?

Stress echocardiography means a pair of cardiac ultrasound imaging examinations, before and after exercise. I assume that coronary blood flow is increased after exercise. Is cardiac ultrasound ...
4
votes
2answers
535 views

By what mechanism does an obstructed bile duct cause excess fat in the stool?

By what mechanism does an obstructed bile duct (for example gallstones) cause steatorrhoea (excess fat in the stool)?
5
votes
1answer
608 views

What could account for an apparent loss of mass at death?

An interesting tidbit floating around the internet these days is that Dr. Duncan MacDougall apparently weighed people shortly before and after death, and found an average of a 21 gram discrepancy, to ...
3
votes
0answers
40 views

Can I purify polyhydroxyalkanoates by heating the cells extensively?

Traditional methods of purifying polyhydroxyalkanoates (PHAs) and other bioplastics made by bacteria involve washing the cells with harsh chemicals or strong bases.I'm interested in maintaining the ...
4
votes
1answer
73 views

How can I save bacillus strains on filter paper without an -80 degree freezer?

I want to save my bacillus strains but I don't have access to a -80 degree freezer. What are possible alternatives?
7
votes
2answers
273 views

How does a pinched nerve cause pain (at the molecular level)?

Is this due to pressure differentials in the surrounding tissue? (Is it possible to have a pinched nerve without compression of the surrounding tissues, and does this cause pain?) What are the ...
9
votes
2answers
5k views

Why is saltatory conduction faster than continuous conduction?

How does spacing apart sodium and potassium channels allow the action potential to travel faster down the axon? This is the reason always cited for saltatory conduction and myelination, but my mental ...
5
votes
4answers
66k views

How long human can survive with just drinking water everyday

Can humans live without eating food, just by drinking water? How long can we survive just by drinking water everyday?
1
vote
1answer
49 views

Introductory text for primatology

I'm looking for a book that provides a good overview of primatology, one aimed more at researchers rather than a popular science book. Ideally, I'd like something with an ethology/ecology angle with ...
10
votes
4answers
13k views

How long can a naked human survive on Mars?

How long can a naked human survive at the surface of the Mars planet? For instance, let's say a worker's base takes fire while he sleeps, and he has to run to the emergency building 200 meters away ...
3
votes
1answer
832 views

What is an epistasis group?

I have been trying to wrap my head around the concept of epistasis for a couple of days now, and I think I understand it, at least at a basic level, but I still don't understand some of the ways that ...
2
votes
1answer
56 views

The Eye, and Camera Lenses

How do near sightedness, farsightedness, and normal sightedness work? If the eye is accustomed to one small focal point, how can it manage a wall of light? And also, how does it process the small ...
4
votes
1answer
167 views

Does biofuel production by microalgae need an extra source of CO₂?

It is necessary to have extra source of CO2 i.e. from a nuclear reactor or factory chimney to produce bio-fuel by microalgae or is it able to do it with the normal CO2 density in the atmosphere?
1
vote
2answers
70 views

Which X-Y chromosomes have the developmental genes for mammals?

I know that for a given mammal, half the chromosomes come from father and half from mother. This is typically denoted as x-y. I've recently read about "toolkit" genes that control how a cell develops ...
3
votes
2answers
144 views

Highly spherical Radiolaria; does this image accurately depict the organism?

If I understand correctly, Cenosphaera spp. is a type of Radiolaria, which is a type of zooplankton. The following is an image of Cenosphaera spp. is from the supplementary material (Figure S2) of ...
5
votes
1answer
415 views

Why are certain aneuploidies more common?

Certain aneuploidies such as trisomy-21 (Downs syndrome), trisomy-18 (Edward syndrome), Turner syndrome (XO) etc are more common than others. I had a vague thought that it is related to chromosome ...
3
votes
0answers
127 views

What is the mechanism by which Melatonin increases dream vividness and intensity in humans?

I'm looking at the wikipedia article on Melatonin and noticed that it mentions vivid dreaming caused by melatonin. I have the "Melatonin and the Biological clock" pamphlet referenced in the article, ...
4
votes
2answers
679 views

Does bleach destroy RNAse activity, and if so, how does it do it?

I am working with RNA samples, and I'm trying to be very careful about RNAse contamination. I have some questions about bleach, though. Some people say that a solution of bleach is enough to destroy ...
5
votes
2answers
2k views

Is wiping with RNAse Zap enough to destroy RNAse activity?

From the RNAseZap MSDS, it is an SDS at some unknown concentration, maybe with some NaOH? Some other links suggest there is some NaOH as well. The Ambion site states that RNAseZap destroys RNAse ...
0
votes
2answers
213 views

Recent and good quality articles on systems biology [closed]

I'm a biotechnology student and I have to write a sort of non-experimental thesis (30 pages long) within the end of a three years study. I'm very interested in the "systems biology" field and I'm ...
1
vote
0answers
186 views

How do cells slowly degrade 5,5'-dibromo-4,4'-dichloro-indigo?

5,5'-dibromo-4,4'-dichloro-indigo is the product of X-gal cleavage, often used as a reporter with B-galactosidase. I've made the (unreferenced) observation that it seems as though the blue product ...
2
votes
4answers
182 views

Are there more descriptive ways of naming genes and gene interactions?

I couldn't help but notice just how non-descriptive the gene names that modern genetics is using. Currently I'm reading "The new science of Evo Devo" by Sean B. Carroll and here are some examples of ...
1
vote
1answer
114 views

How can I clean phenol extracted RNA?

I extracted RNA from skin and quantified it in an Nanodrop machine. The 260/230 ratio was very low and two peaks appeared in the absorbance curve, but the RNA is ressuspended in RNAse free water. How ...
2
votes
1answer
80 views

What is the name of the baboons that live in Saudi Arabia

In Saudi Arabia there are a lot of baboons in the mountain area. I would like to know what's the name of this specific baboons so I can read about them more:
5
votes
1answer
4k views

Why does blood come from mouth when people are shot in the chest area?

In almost every movie scene when a character is shot in the chest area, some blood comes from his mouth or sometimes even coughs blood before he dies. Are these kind of scenes realistic/possible? If ...
3
votes
1answer
160 views

Are any organisms known to use meiosis I to create non-identical offspring asexually?

So, there are numerous species of animals who use parthenogenesis, but to my knowledge the reproduction is clonal. That is, the offspring are identical to the mother. Are there any documented cases ...
4
votes
1answer
58 views

What is meant by “alien” probe in a microarray?

In my lab we did a microarray to analyze differential gene expression in S. cerevisiae treated with UV irradiation. We are now analyzing the results and one of the up-regulated genes is labeled ...
2
votes
1answer
216 views

Why is herpes virus neurotropic?

A neurotropic virus is a virus which capable of infecting nerve cells. Herpes simplex virus (HSV) has low neuroinvasivesess and high neurovirulence. HSV is transmitted in vesicle fluid, saliva and ...
6
votes
3answers
2k views

Histidine aromaticity

I understand that the imidazole ring in histidine is aromatic. I also realize that it retains it's aromaticity when protonated. I am wondering why it is not mentioned at all in basic text books such ...
3
votes
2answers
620 views

Detecting Introns and Exons

I know that when RNA is transcribed from the original strand of DNA it contains introns and exons, and that the introns are spliced out of the strand to provide genetic diversity. However, what I ...
2
votes
1answer
51 views

I'd like to know the name and a few details of a certain time-keeping structure in the human brain

I once heard of this structure on the Discovery Science channel and have since forgotten the name. The details I remember about it were that it is the central time-keeping device for the brain located ...
1
vote
1answer
77 views

qrt-pcr and short fragments

I plan to measure the effects of Tenofovir a Nucleotide analog reverse-transcriptase inhibitors useing qrt-pcr with HIV-RT as the rt enzyme. Tenofovir causes early termination of the reverse ...
3
votes
2answers
464 views

The effects of dust particles

When sun rays shoot through my house from a window, sometimes if the lighting is correct, it will reveal a huge amount of floating particles and dust. Are these particles dangerous to humans if you ...

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