0
votes
1answer
80 views

What species of bird is on this coin? [closed]

What species of bird is depicted on this coin? http://www.artic.edu/aic/collections/citi/images/standard/WebLarge/WebImg_000100/139651_846511.jpg Thanks in advance for your help!
5
votes
1answer
324 views

Solvent Accessibility, the 20% cut-off method

I'm reading the papers linked below and all three of them mention a 20% cut-off for buried/exposed residues, by calculating a relative solvent accessibility (RSA) value. I understand how the RSA is ...
2
votes
0answers
35 views

Can the Human body Synthesise Vitamin D from Phytosterols?

I know that the human body can synthesise vitamin D from cholesterol, but can it do so from phytosterols?
3
votes
1answer
456 views

Difference between “transcriptional activity” and “RNA expression”

I am working with a network object where the nodes are different events in molecular biology. Specifically; Catalytic activity of X, RNA expression of X, GTP-bound activity of X, Kinase activity of ...
9
votes
2answers
76 views

Can we disambiguate competing molecular mechanisms of learning and plasticity by measuring electrical activity of neurons?

I have been reading with fascination about the several molecular- and cellular-scale mechanisms and structural changes that underlie what we refer to as long-term plasticity. For instance, [1], [2], ...
3
votes
1answer
1k views

Can a person become addicted to tea?

Can one become addicted to tea like coffee addicts or smokers? I heard there are some common substances in tea and coffee, do they cause addiction?
4
votes
3answers
178 views

How does natural selection favour large body mass and size (or so it seems)

I was walking through a park this afternoon and observed a few birds having fun flying around and it got me thinking why would natural selection favour birds with flesh at all if it hinders their ...
1
vote
1answer
82 views

What factors must be taken into account for the maintenance of the immunogenicity of ovalbumin antigen?

What factors must be taken into account for the maintenance of the immunogenicity of ovalbumin antigen? If the ovalbumin is aggregated, could we inject it for induction of immune reponse?
4
votes
1answer
154 views

How can the child and the mother have different blood types?

As far as I know the fetus is fed by the umbilical cord which basically connects his/her circulatory system with the mother's in order to supply oxygen and nutrients. But how is this possible if they ...
2
votes
1answer
3k views

Melting point of a fatty acid?

What factors determine the melting point of a fatty acid? Chain length The number of methylene group The ionized state of the fatty acid Its degree of saponification Its ability to alter the ...
11
votes
4answers
229 views

What was the reason for some plant and animals to become giant in course of evolution?

The dinosaurs, mammoths, giant plants etc are known to be bigger than modern animals. I wonder why they had been lived and why they are not living now? I really don't know much but is it something ...
1
vote
1answer
11k views

I'm 20. Can I still grow taller? [closed]

I'm 20, in about 6 months I turn 21. For some time I've been wondering whether there are natural, non-surgical and non-pharmaceutical ways that humans can continue to grow after reaching adulthood. ...
5
votes
1answer
299 views

Are there grass or fiber eating birds?

My understanding, that may be wrong, is that cellulose/fibre has little nutritional value to many animals because it's hard to break down thus making consumption inefficient. However, Ruminating ...
4
votes
1answer
302 views

What plastic eating organisms are there to help with plastic in landfills problem?

I see some popular science articles on the plastic eating bacteria and fungi appearing on the web since 2009. Most of the articles praise discoveries, because such organisms promise to break down ...
4
votes
2answers
764 views

Advice on Cell Biology texts by Alberts

I am currently reading "The Chemistry of Life" by Rose. It's a great book (to me as a lay reader at least) and an interesting topic so I am interested in pursuing some of the further reading he ...
5
votes
1answer
205 views

Does GTP-γS (GTP gamma S) bind all GTP-binding proteins?

I've just read an article Rab10 GTPase regulates ER dynamics and morphology - Nature Cell Biology 15, 169–178 (2013) doi:10.1038/ncb2647. In this paper, to identify Rab proteins in ER, first they ...
3
votes
2answers
544 views

What kind of microscope should be used to view biological structures (such as spores) roughly 5 µm in length?

I would like to be able to identify genera of fungi based on the shape, size, and colour of spores. So the requirements are: Must be able to view a 5 micrometre object clearly with reasonable ...
2
votes
1answer
40 views

What's the simplest set-up to demonstrate soiless plant growth to middle school students?

I'm looking for a simple, inexpensive way to demonstrate that soil is not needed for plant growth to middle school students. I plan to germinate bean seeds in cotton, but where do I take it from ...
7
votes
1answer
71 views

Cell Respiration and Oxidative Phosphorylation

Why and how does the proton travelling through the stalked particle in the inner mitochondrial membrane, cause a conformational change in the ATPase?
5
votes
2answers
2k views

Does ethanol destroy RNase?

I've gotten conflicting advice on this: some people believe one can remove RNase contamination simply by spraying the bench, pipettes, gloves, etc. with ethanol. Others think ethanol does not destroy ...
1
vote
1answer
337 views

Where are doxycycline's anti-inflammatory properties derived from?

I have been looking at this antibiotic called doxycycline which is used mainly as an antibiotic. It has however some interesting anti-inflammatory properties. Does anyone know where these ...
1
vote
1answer
176 views

Is it true that oxygen has a diffusion rate in air 10,000 times greater than in water? [closed]

According to the Wikipedia page on the design of gills, oxygen has a diffusion rate in air 10,000 times greater than in water. Is that true? The WP entry refers to: M.B.V. Roberts, Michael Reiss, ...
3
votes
0answers
678 views

What are the factors to consider when determining the sample size for a given study?

Say I'm designing a retrospective study (where I'd collect data from various schools for the last 5 years) to see if consuming milk can contribute to childhood obesity. How do I decide on how many ...
4
votes
2answers
173 views

Confusion related to gene expression

I have a set of gene expression data downloaded from http://www.ncbi.nlm.nih.gov/geo. I have two sets of data, one is the raw probe intensity data set in the form of CEL files. Another is processed ...
5
votes
1answer
273 views

How to do western analysis to lung tissue?

I am working with lungs from mice, and I want to do a western blot analysis to my samples. I am having trouble with this because my images turn out very "messy", with a high background. Perhaps I ...
0
votes
1answer
172 views

Are lactic acid and prolactin rise after exercise connected?

I've been reading about prolactin, a human hormone. Apparently it's levels within the brain can raise after exercise, although the mechanism is not clear to me. I'm interested of there is any ...
5
votes
1answer
1k views

Why are pili more common in Gram negative bacteria than in Gram positive?

Although pili have been observed in some species of Gram positive bacteria, the preliminary research that I have done indicates that pili are significantly more common in Gram negative bacteria. Is ...
3
votes
3answers
155 views

Super-resolution imaging in vivo

Are there any microscopy modalities or techniques for in vivo imaging at higher resolutions than the diffraction limit? I was looking at this list: Super resolution microscopy, but they don't talk ...
1
vote
1answer
74 views

Is it possible to give a person an allergic reaction in a very specific place?

Can I give a person an allergic reaction at a very specific spot in a tissue? And if so, how accurate can i get?
1
vote
2answers
185 views

Why does throat 'burn' when you've got a common cold?

Apart from pain when swallowing, there's also a persistent feeling of throat 'burning' in the same area. What causes it and why does it feel that way?
4
votes
2answers
210 views

Hershey and Chase experiment

http://www.youtube.com/watch?v=3QJ4CjFsflA This is a link to Hershey and Chase experiment. According to this experiment, we conclude that DNA is the genetic material. But how do we conclude that DNA ...
4
votes
1answer
141 views

Can the immune system stop plasmodium from being active?

Suppose a female Anopheles infected with Plasmodium bites someone and transmits Plasmodium to their body. Can that person's immune system be strong enough that it can kill the Plasmodium before it ...
2
votes
0answers
114 views

Resuspending Cells from a filter plate

My experiment involves pulling down cells on to a filter plate for a variety of assays. However, I want to ensure that my cells are alive so I am trying to resuspend them so that I can do an accurate ...
2
votes
1answer
173 views

Is there an “Adam and Eve” for each new trait during (not just human) evolution? [duplicate]

Do new beneficial mutation evolve simultaneously and independently with several individuals of the same specie or only with one specimen who then transfers it to all of the specie? In other words, ...
5
votes
1answer
161 views

What is a Mitochondrial Eve and Y-chromosomal Adam

I've read this question: What kind of event would cause the current Mitochondrial Eve to be replaced by a new one? And the values in Wikipedia about Mitochondrial Eve and Y-chromosomal Adam and I am ...
3
votes
1answer
106 views

Do serotonergic (5-HT2A-mediated) psychedelics elicit stimulant effects?

I know that 5-HT2A partial agonism is the key mechanism of action of serotonergic psychedelics but I also know that some research (e.g. the selective (no activity on any other known receptor sites) ...
1
vote
1answer
143 views

Does the NMDA antagonist, Memantine that's used to prevent Excitotoxicity cause brain damage?

Does the NMDA antagonist, Memantine that's used to prevent excitotoxicity in Alzheimer's disease (AD) and Dementia with Lewy Bodies (DLB) cause brain damage? I know that in rodents NMDA antagonists ...
1
vote
0answers
19 views

Which Receptors are involved in Psychedelia/Psychosis?

Which receptors are involved in Psychedelia/Psychosis? I know that the 5-HT2A, 5-HT3, D2, κ-opioid and NMDA receptors are likely involved in psychosis.
0
votes
2answers
321 views

Which range are the Therapeutic Indices of Currently-Prescribed Benzodiazepines in?

A compound's therapeutic index is defined as: $$TI = \frac{LD_{50}}{ED_{50}}$$ What range are the therapeutic indices of benzodiazepines in? For the method of administration I would prefer ...
10
votes
2answers
489 views

Could hydrogen replace oxygen in cellular respiration?

I was wondering what oxygen actually does in the body. I have seen a few answers to other questions that involve the electron chain and I am really not sure what that is. So I was wondering what ...
2
votes
2answers
41 views

Studying changes in DNA for causes of cancer

First of all let me say that I'm not into Biology myself... but I have a question for those of you who are. From what I've read, cancer is caused by 'faulty' DNA that behaves abnormally. Mutations ...
6
votes
1answer
93 views

Proteins that are strongly overproduced in E. coli and S. cerevisiae?

I'm looking for some pointers to proteins that produce at really gigantic levels in E. coli and yeast (S. cerevisiae). Can anyone point to some champion proteins? Even in inclusion bodies and non ...
8
votes
2answers
365 views

Why is blood pressure higher the more distal an artery is?

Why is blood pressure generally higher in more distal arteries?
7
votes
1answer
443 views

Which sex has higher variance of reproductive rate in modern societies - male or females?

Who has a more varied reproduction rate in modern western societies - men or women? The average rate is the same of course, but I wonder which sex have higher variance - higher variance means that ...
4
votes
1answer
178 views

In the diffraction pattern of a protein crystal what exactly determines the intensities of the spots?

What I have read is that the contents of the unit cell affect the intensities, but how? I am also unclear on why you need to know the symmetry of the unit cell, what is that used for? I understand ...
1
vote
1answer
145 views

What is the biochemical reason for mental fatigue?

Is it known exactly why the brain needs sleep? What's dropping low / going high when we experience mental fatigue? I can see why low glucose could result in mental fatigue, are other reasons known?
1
vote
1answer
108 views

How do circulating androgens contribute to higher rates of hirsuteness in some women?

I was reading up on ethnic groups in which the women are naturally more hirsute (such as South Asian women) in the context of evolving standards of beauty. I came across this statement on a forum: ...
2
votes
1answer
52 views

Trigger allergic reaction in non-allergic people?

Is there a proven way to trigger an allergic or allergic-like reaction in non-allergic people? I have wondered if this is possible, since allergies are basically just a form hypersensitivity - so ...
9
votes
2answers
5k views

What is the difference between SOLiD, 454, and Illumina next-gen sequencing?

I've started teaching myself about next-generation sequencing in preparation for a new job, and I'm wondering what the main differences are between the 454, SOLiD, and Illumina/Solexa machines, in ...
3
votes
2answers
220 views

Short-term Lamarckism in asexual single cell organisms

I was reading through the Karr et al. (2012) whole-cell computational model. One of the things they did was to induce single-gene disruptions in their model. They observed several to be fatal, but: ...

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