1
vote
0answers
20 views

Differential Scanning Calorimetry for bacterial membranes

I would like to study the freezing and melting of bacterial membranes and would like to use Differential Scanning Calorimetry (DSC) to obtain the glass transition temperature of the membrane. However, ...
6
votes
1answer
3k views

Why extract DNA from certain white blood cells instead of whole blood?

In my lab, human DNA is extracted from whole-blood samples. I don't actually do the extractions and I am not familiar with the specific protocol but I understand that platelets and red blood cells ...
2
votes
0answers
67 views

What fraction of biomass is cultivated by humans? Have we increased the number of large animals?

What fraction of "large animals" are domesticated by humans, compared to those who are wild? I mean cows, pigs, sheep, horses, dogs, cats in relation to comparable wild animals. Different measurements ...
3
votes
2answers
592 views

What are the buoyancy control mechanisms of Chambered nautilus?

I'm currently working on an underwater robot and was hoping to use the principle used by the nautilus for buoyancy control. So how do the Chambered nautilus control its buoyancy?
2
votes
1answer
70 views

Why do oncogenes show genetic dominance?

As we know that tumor suppressor gene causes cancer only when both the alleles are recessive in nature.But in case of oncogenes if only one allele is dominant it can cause cancer.Why in case of ...
11
votes
1answer
972 views

Can you identify this bird?

Can somebody please identify this bird for me? I spotted this in July 2012 while birding in Ranganthittu Bird Sanctuary.
3
votes
1answer
390 views

Consumption of NAD+ in glycolysis

Out of 10 steps in glycolysis, only one reaction- Glyceraldehyde 3-phosphate (G3P) to 1,3-bisphosphoglycerate (PGP), uses NAD+ and thereby producing NADH. Furthermore, this very step is solely ...
6
votes
1answer
226 views

If evolution is a gradual and continuous process, how can we say humans came about 200k years ago? What is so special about that point in time?

It just seems arbitrary to me to say "ok, now THIS is officially a human" when you could look at its parents and find no noticeable differences. At no point in the line of my ancestral history is ...
4
votes
0answers
43k views

Does CPH4 exists? [closed]

What is the purpose of CPH-4? Is it well represented in the movie Lucy?
7
votes
1answer
150 views

Organisms in food deposits

I have just discovered that my kitchen sink pipe has been leaking for quite some time (possibly months) which has resulted in water and food deposits collecting in my cupboard. I smeared some of the ...
5
votes
1answer
134 views

What is the name of this plant with many purple blooms with orange inner parts?

I have photographed the following plant in Pittsburgh, PA. It has many blooms and every bloom is very small (about 5mm diameter), purple on the outer and orange in the inner. You can see it here: ...
1
vote
1answer
51 views

How is the GenBank used in typical biological research? [closed]

How is the GenBank used in typical biological research? According to the GenBank statistics, the database contains about 100 million sequences. I find it difficult to understand why is all that data ...
3
votes
2answers
275 views

Standard Process Identification of New Disease outbreak Causing Pathogen

Is the any standard procedure or protocol followed for the identification of cause of new disease outbreak(or new pathogen)? Is it different for different countries?
4
votes
1answer
163 views

Is the heterotroph hypothesis universally accepted?

I was wondering whether there are hypotheses that take a different approach that is contrary to the heterotroph hypothesis. The heterotroph hypothesis states that autotrophs evolved from heterotrophs ...
15
votes
2answers
6k views

Do identical twins have the same fingerprint?

When there is every thing same from their genes to their phenotype so then why they don't have same fingerprints?
4
votes
1answer
4k views

why does blood when oxidized over time become bluish green?

Oxygenated blood is bright red and deoxygenated blood is dark red or brown. If you take oxygenated blood and leave it in the air it will turn dark red, then brown, then finally a bluish green from ...
2
votes
1answer
143 views

Is an Eidetic Memory (or other unusual forms of memory) less susceptible to anterograde amnesia?

I'm a physicist, so as a fellow scientist I want to apologize because this question will be entirely based on anecdotal inferences and I am well aware how irritating that can be. I have an eidetic ...
5
votes
1answer
11k views

Calculation of the bacterial growth rate from a spectrophotomer growth curve

Typically the microbial growth in liquid cultures is monitored by turbidity. Data is obtained with a spectrophotometer to measure optical density at 600nm. The slope of the bacterial kinetic curve in ...
1
vote
0answers
24 views

Potential evapotranspiration constant for trees in the area of London

I am trying to find the ET0 (Potential evapotranspiration) under the climate conditions of London (UK) and Coimbra (Portugal) for each month. From what I understand these data is available in the FAO'...
2
votes
1answer
351 views

What is the chemical process involved in human hairs changing colour after sun exposure?

After a day at the beach, my skin tans due to Melanin. But I also observe the black hairs on my arm turn a blond colour. My question is What is the chemical process involved in human hairs ...
2
votes
4answers
129 views

determine longest poly-purine tract

how to determine/ find the longest poly-purine tract in any genome and this needs to be on the E. coli genome . is it to figure out the polypurine tract and then figure out the longest chain ? or is ...
5
votes
1answer
320 views

What is the name if this glittery fly seen in Pittsburgh?

I have photographed the following fly which is iridescent green in Pittsburgh, PA. I guess it was about 0.5-1.5cm long. Can you help me to identify it?
1
vote
1answer
719 views

For how long can a person drink sea water?

How long could a person of lets say 18 years be able to drink sea water without getting too much into trouble ? Or can a person drink it without noticing that it is a very bad idea ? I don't mean in ...
3
votes
1answer
290 views

What's the purpose of colorful mushrooms' caps?

What's the purpose for many mushrooms to have colorful caps? Is not it is in their interest to hide as well as possible? Or there are mushrooms that propagate by being eaten, like fruits? Why not all ...
2
votes
2answers
176 views

Convergent evolution of fruits

Many fruits are not homologous, originating from different parts of a plant. Yet they all have similar properties: Ripe fruits all have yellow to dark red color They all have a lot of water and ...
1
vote
1answer
131 views

Can you measure plasma glucose with a regular glucose meter?

I'm wondering if plasma glucose can be measured with a regular glucose meter and strips like this. I know these meters are normally used to measure whole blood glucose, but can they measure plasma ...
17
votes
4answers
464 views

Machine learning for light microscopy — problems to solve?

I would like solve some biological problems that would improve the state-of-the-art of biology or bioinformatics. In particular, I want to apply machine learning on light microscopic images. The ...
1
vote
2answers
295 views

Microscope scale bar

In some microscopic images, there is a bar scale at one of the corners or near a specific object. How are they added to the images? Does the slide have some markers, or are they digitally added? If so,...
1
vote
1answer
182 views

Why are high levels of epinephrine and low levels of cortisol signs of stress?

According to my psychology textbook (Psychological Science: Modeling Scientific Literacy), high levels of epinephrine and low levels of cortisol are signs of stress. However, earlier in the textbook ...
2
votes
2answers
436 views

Is dried grain dead or dormant?

Is dried grain considered dead or dormant botanically? Related to a BH-SE question.
4
votes
1answer
109 views

Could habitat selection pattern be deformed in environment with low variability?

It is possible that strong (clearly visible) pattern of selection towards particular parameter is detectable only in environment with high variability (difference between used (red) and non-used (grey)...
0
votes
3answers
755 views

What is the purpose of DNA? [closed]

My very basic understanding is DNA gets transcribed into RNA by effectively replacing thymine with uracil, then RNA is translated to make proteins. Looking at it from an engineering perspective, it ...
3
votes
2answers
225 views

Human Evolution in Modern Times

I understand that evolution occurred to form the current hominids from a common ancestor millions of years ago. As evolutionary processes take a long time, is there proof of evolution occurring with ...
1
vote
1answer
19 views

Are efflux pumps mutations or are they originally present in N. gonorrhoea?

I'll start by saying that I am no biologist. I am a math major trying to create a mathematical model for gonorrhea strain competition. My assignment is to create a model similar to a model that was ...
1
vote
1answer
54 views

What could cause no pain but sense of touch?

What could cause a mammal to have and respond to a sense of touch with only isolated numbness but not feel pain?
1
vote
1answer
108 views

Dataset of microscopic images before and after staining?

I am looking for a freely distributed dataset of microscopic images. I am hoping to find a dataset that would feature histological images before and after staining (e.g. H&E or some other standard ...
2
votes
2answers
291 views

Can a broken thumb/finger bone not require realignment of the bone?

Is it possible that a finger/thumb bone fracture is so superficial, that the doctor does not need to realign (re-set) the bone before applying the cast? Or does it always require for even a finger/...
4
votes
1answer
78 views

X-inactivation in ovaries

Background In all eutherian (mammals excluding the marsupials), the female (who is $XX$ for the pair of sexual chromosomes) inactivates one of her $X$. This is called dosage compensation. This ...
4
votes
1answer
101 views

Relationship between mN and mg in vessel contraction studies?

What is the relationship between mN and mg as the units involved to measure the changes in contraction? A tool most widely used is an instrument called myograph. In these exoeriments, either units of ...
1
vote
1answer
128 views

Datasets of aligned nucleotide sequences [closed]

Where can I find some datasets of aligned nucleotide sequences? And what should I assume about the accuracy of the alignments there? (I would like to use such datasets for training the alignment ...
3
votes
2answers
403 views

How are DNA segments selected in PCR?

I understand that in PCR we're able to amplify only selected portions of the DNA... however despite reading it from multiple sources, I cannot figure out how this selection actually takes place. I ...
6
votes
2answers
11k views

Why was the Davson-Danielli model rejected?

According to my textbook, Davson-Danielli's model of a phospholipid bilayer sandwiched between two layers of globular protein was incorrect. The nonpolar protein portions would separate the polar ...
1
vote
1answer
291 views

Waste generation by embryo [closed]

How does an embryo produce waste products even when its organ systems are not developed fully ? How does the placenta identify or differentiate waste materials from embryo ? Which organelle or ...
1
vote
1answer
64 views

Is this ladybird larva secreting a protective fluid?

I know that adult ladybird beetles can secrete a fluid to keep predators from eating them. Can the larvae do that too? Or are these yellow droplets something else?
3
votes
1answer
353 views

is it necessary that every theca of an angiospermic anther must contain two microsporangia

i basically don't know the procedure or sequence of steps involved in the formation of anthers but i have read it somewhere it is formed from the dedifferentiation of shoot apical meristem of the ...
3
votes
1answer
128 views

Could the growth rates of Vibrio vulnificus be affected by an oil spill?

I live on the Gulf Coast, and Vibrio vulnificus has recently made the news due to an increase in the number of reported infections. Naturally, it has people around here worried. I live in an area that ...
0
votes
1answer
56 views

Regarding apoptosis and turning it 'back on'

Is there some chemical or chemicals or even special molecules that can be 'injected' into cancer cells that will turn any Apoptosis mechanisms 'back on'? Or maybe chemicals and/or molecules that ...
1
vote
1answer
49 views

Mechanism of DNA gyrase inhibitor

Why DNA gyrase inhibitor, such as Nalidixic acid and Norfloxacin, do not stop gyrase from cutting DNA helix but only prevent them from decatenation replicating DNA?
4
votes
1answer
90 views

Can we attack viruses by attaching proteins and such to their shells?

Haven't looked into this to very long, but an initial search didn't return anything. HIV uses certain co-receptors to enter our cells. Could we flood the blood stream with specially designed ...
6
votes
2answers
407 views

How is photosynthesis observed?

How is photosynthesis observed? Say I have plants A and B, and I want to find how fast they are able to turn carbon dioxide into oxygen. How would I experiment this? Say I have one plant A, which ...

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