4
votes
1answer
383 views

How does a plant cutting develop roots?

Please correct me if my understanding is incorrect; I understand branch/stem, and root are composed of different types of cells. Yet in some plants (e.g. rose, bougainvillea) a cutting from the stem ...
11
votes
1answer
468 views

How does a jumping spider manage to “jump” on the ceiling?

I just witnessed a small jumping spider jump on some kind of louse or bed bug on the ceiling. How does it do that without falling? I have yet to find a high-speed-camera video of a jumping spider ...
5
votes
1answer
672 views

Total amount of CO₂ / Oxygen in Bloodstream in Humans

How much carbon dioxide and oxygen from/for respiration are in the bloodstream at any one time? (mass per litre of blood or similar) And would there be much more aside from the blood in tissue, e.g. ...
5
votes
2answers
5k views

Why do we sweat after drinking water and running?

Why do we sweat after running? Also we sweat sometime after drinking lots of water. Why it is so? Can someone please enlighten me in this regard?
5
votes
1answer
262 views

Are there any side-effects from a mosquitoes extinction?

Suppose that we have the ability to make mosquitoes extinct, what would the side-effect of such extinction be other than the fact that there won't be any mosquitoes left? Is it worth it to make ...
11
votes
3answers
315 views

Most suitable biodiversity index

I am conducting an investigation into the effect of two different grass management techniques (grazing vs. machine-mowing) upon floral biodiversity. I have collected my data and now need to process ...
2
votes
1answer
387 views

Will fruit/seed of a bonsai yield another bonsai plant/tree?

With practice one can create a bonsai; no complicated modification of the DNA in a high-end lab required. The bonsai will even beget bonsai fruit. What I am curious about is - if such bonsai fruit ...
9
votes
1answer
1k views

How does this illusion work?

I found this image on Google+ If you shake your head you can see a portrait of a person. Can anyone explain how the image is constructed in the brain?
0
votes
2answers
2k views

Autosomal Recessive Trait when skipping one generation

I learned recently that given a pedigree it is possible to tell whether a disease is autosomal recessive by observing if the trait skips a generation. If the disease does skip a generation, then the ...
5
votes
1answer
528 views

Primer Dimer / Hairpin Algorithms

What are the algorithms / methods in use for the calculation of primer dimers and hairpins? As an example, IDT's OligoAnalyzer tool will generate these analysis given particular sequences. The ...
11
votes
2answers
366 views

How deep in the soil can a seed be placed and still develop into a plant/tree?

The selected answer to How does a plant grow before photosynthesis is possible? indicates that a sprout grows beneath the soil using the food stored within the seed. Does this limited ready food ...
14
votes
1answer
204 views

Paralogous genes in genome-wide association studies?

Has anybody tested if paralogous genes are over-represented among the genes identified by genome-wide association studies (GWAS)? For example, if a GWAS study finds 200 genes associated to the ...
9
votes
1answer
469 views

Is it possible to lose synapses over time?

I mean, what if a person is for a long time submitted to conditions in which his mental capacities are not explored, are the synapses undone? I've heard that drugs may cause such an effect, but what ...
1
vote
1answer
3k views

What is the mIU unit as used in hCG hormone levels?

My girlfriend is in her very early pregnancy, and has provided several blood samples by now where the doctors measure her hCG levels. The hCG hormone level is measure in a unit called ...
4
votes
1answer
90 views

How would one describe the R-factor in crystallography?

Yes, there is the wikipedia definition, but how would one explain this concept to a non structural biologist?
4
votes
2answers
118 views

Sequencing from PCR

As far as I understand it, PCR can be used to make many copies of one gene. My question is, is it possible to sequence DNA after PCR and is it easier than sequencing it via other methods. If it is ...
1
vote
0answers
26 views

Photosynthesis/Plants Question [duplicate]

Possible Duplicate: How long will a vegetable live for after being harvested? Exactly when do plants "die," as in stop functioning to live? If, for example, you pick a plant and start to ...
4
votes
0answers
49 views

Is it possible to repopulate lactase in the stomach? [duplicate]

Possible Duplicate: Can an adult without genetic lactase persistence still develop a tolerance for dairy foods? In my younger years, I don't seem to have a problem drinking milk. Nowadays, ...
11
votes
7answers
3k views

How did the first self replicating organism come into existence?

When people try to explain evolution, they tell me that evolution is a cumulative result of mutations & natural section of the more superior individuals of a particular species. I think I'm fairly ...
3
votes
3answers
263 views

Extreme examples of protein translation/use coupling/decoupling?

What are known extreme examples of protein translation/effect coupling/decoupling? For example, examples of proteins that are immediately used at the time the have been translated and vice versa, ...
26
votes
1answer
1k views

Why do ants live so long?

I was surprised to learn that worker ants in some species live many years. I would have expected a lifespan of a few weeks or months (which is apparently the case for many species). What factors ...
6
votes
2answers
3k views

How do I deal with sticky and viscous samples from cell lysates?

To check a protein expression I pelleted a small amount of E. coli before and after induction and lysed them by redissolving them in SDS-PAGE loading buffer and heating them to 95 °C for 1 minute. ...
3
votes
1answer
59 views

What are treatable foetal conditions during pregnancy?

What are different foetal conditions during pregnancy that could be treated with appropriate prenatal genetic testing? I only know that pregnant women are encouraged to take certain supplements to ...
5
votes
2answers
3k views

What is the appropriate method to send a strain?

We are planning to send an ecoli strain to another lab. What is the appropriate way to do so. No MTA is required but the options seem to be using filter paper or sending a glycerol stock on dry ice.
9
votes
2answers
409 views

Is there any recent evidence for the aquatic ape theory of human evolution?

aquatic ape theory suggests that many features that distinguish humans from their nearest evolutionary relatives emerged because the ancestors of humans underwent a period when they were adapting to ...
7
votes
1answer
1k views

Why is the Kakapo more attracted to humans than its own kind?

The Kakapo can be seen in this video by BBC. It is said that the species is strongly sexually attracted to humans. Why could this be the case?
2
votes
1answer
63 views

variation in expression accounted for a SNP — what's a usual percent?

I am reading a GWAS paper that found a SNP associated to predisposition to colon cancer and was assessed for gene expression of the nearby gene. They found that the genotype accounted for 55% of the ...
5
votes
1answer
121 views

Is it possible to sequence only the 16S rRNA component? If so, how?

There have recently been several papers on using 16S rRNA as a way of identifying species (here, and here). I'm wondering if it's possible to sequence either just that subunit of the ribosome or just ...
4
votes
1answer
435 views

T7 promoter leakiness

Can a gene be expressed under the T7 promoter in an E. coli strain (e.g. DH5 alpha), which does not have the T7 polymerase gene encoded in its genome? In other words, is T7 promoter leaky? To be ...
12
votes
1answer
1k views

Why does hair turn grey or white, and why does it happen later for some?

The question is pretty simple: what is happening molecularly when hair turns grey or white? I would imagine that it is due to the lack of a particular compound. I'm also interested in why some ...
2
votes
1answer
590 views

Why does ampicillin in solution turn yellow?

I have a universal tube with 10 mg mL-1 ampicillin. When I got it, it was supposed to be sterile. It was opened for approximately 20 minutes for an experiment and has since been standing around sealed ...
5
votes
1answer
126 views

Is there any reason the common housefly continues to return to an area?

This might come off as a really silly question. But I'm wondering (especially in the case of food) if there is any reason a fly would continue to try and sit on top of a piece of food even after ...
4
votes
2answers
225 views

Is Homo sapiens the only species capable of prioritization?

Just what the title states--given an absurdly large number of assignments to perform in a limited time-frame we usually attempt to do the most important ones first. Is this ability to define and ...
5
votes
1answer
408 views

Do all plants photosynthesize with equal efficiency?

Just what the title states. Given identical, necessary and favourable conditions (Probably nutrients, humidity, and light but what I mean is all necessary requirements are fulfilled) - Is ...
15
votes
2answers
912 views

Impact of Alan Turing's approach to morphogenesis

Shortly before his untimely passing, the computing pioneer Alan Turing published his most cited paper The Chemical Basis of Morphogenesis (1952). The central question for Turing was: how does a ...
11
votes
2answers
2k views

Why do only only two sexes exist for animals?

Why, from the natural selection point of view, do only two sexes exist for animals?
1
vote
0answers
63 views

Is pure (100% H20, (near to no) solutes) water toxic to living organisms? [duplicate]

Possible Duplicate: Death because of distilled water consumption I know about the effects and myths about drinking distilled and/or deionized water. I'm not asking about such substances. I ...
-3
votes
1answer
352 views

Why hasn't mother nature made us aware of our lizard brain? [closed]

In many personal improvement books I've read, people make a distinction between 2 parts of our brain: the logical brain, dealing with logic, judgement, thinking; what makes Humans different than ...
6
votes
1answer
224 views

What's the state of the art in designing and creating your own life forms?

What's the state of the art for solving the following problem. You imagine a set of features that you want a life-form to have. Just to take an arbitrary example, say you want your life-form to have ...
10
votes
2answers
201 views

Is the function of adjacent genes correlated?

Do genes that occupy a similar locus on the genome have correlated function, specifically in human beings? It is my understanding that adjacent genes are inherited together, and so location plays a ...
1
vote
2answers
715 views

Shouldn't evolution have taken care of baldness already?

It is my understanding that the hair on the head is there to protect us from sunburn. I've never seen a bald animal, so isn't evolution in charge of addressing these type of things? How is it that ...
12
votes
2answers
4k views

Do men have significant hormonal cycles?

I know there's a similar question here. But that discussion dissolved into lunar cycle and a correlation with it. I want to find more towards the original question of is there a periodic hormone ...
3
votes
2answers
236 views

Do both TSG and Proto-oncogenes have to suffer mutations to cause cancer?

I'm having a conceptual nightmare trying to understand when a group of cells may become cancerous and the more resources I consult the more confused I seem to get. In order for a cell to become ...
7
votes
1answer
78 views

How does one measure the length of telomeres?

My questions are: What techniques are available for doing so? Are they destructive ? What is their accuracy ?
5
votes
3answers
60 views

Do you know of any disease where HLA / MHC association discovery has led to better treatment or management?

If we discover an association between a disease and a particular HLA type (MHC class I or class II molecule) then it may provide us with some insight into the disease in a very basic way. However, ...
5
votes
2answers
208 views

How high is the energy yield of photovoltaics compared to photosynthesis?

I'm not an expert in plant physiology. I was wondering if, per square centimeter, leaves are converting more or less energy than photovoltaic systems. Can this be estimated? How?
6
votes
1answer
992 views

Examples of intracellular parasites of medical or economic importance?

What are examples of intracellular parasites of medical or economic importance? I have read that Xanthomonas oryzae is an intracellular parasite in rice that produces proteins able to cause changes in ...
13
votes
3answers
3k views

When has an organism evolved enough to be called a new species?

Imagine that we take a population of horses, split them in half and place them in completely different environments. The two species will evolve separate from each other and because the environment is ...
0
votes
1answer
589 views

Are there examples of the green beard effect in humans?

Green-beard effects are genes that: Produce an effect that can be detected Produce preference to others with the same effect Are there any examples of this in humans?
9
votes
3answers
1k views

Why does the butterfly have a cocoon stage in its life cycle?

Why does the butterfly have a cocoon stage in its life cycle? It could have simply grown up within the egg/cocoon, and emerged as a butterfly. Instead it is first an egg, then a worm, then a ...

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