12
votes
1answer
539 views

Why do we feel tired if we sleep excessively?

When we eat, finally we feel full. I know which mechanism causes the sensation of being full. But when we sleep excessively we often still want more sleep. Why does this happen? Is there a mechanism ...
0
votes
2answers
662 views

Why have humans evolved conciousness?

Why did humans/animals evolve to become self-aware of their own thoughts. That is, why don't humans act and compute like a machine, or walking zombie. In my mind, such creatures would still be as ...
5
votes
2answers
3k views

How does HCl does not burn our stomach?

How does the digestive acid (HCl) not burn the surrounding skin of our stomach? It digests majority of raw food we eat but how does it stays safe in our stomach? Also, how does the stomach retains the ...
2
votes
1answer
82 views

Is anaerobic activity during ketosis possible?

When a person's glucose and glycogen stores are depleted, which can occur due to fasting or due to a diet consisting largely of fat (like eskimo diets), the body produces its energy by breaking down ...
2
votes
0answers
36 views

Glutamine analysis

I use to run a method to analyse all the amino-acids in a food sample. For that I have to hydrololyse the sample and in the last stage of the method I read the amino acids with a ion exchange ...
3
votes
1answer
88 views

How to evaluate the efficacy of an antibody for fluorescence microscopy?

I'm trying to evaluate data taken from fluorescence microscopy with antibody staining, and am wondering whether there is any standard way to evaluate the specificity of the antibody for such ...
4
votes
2answers
161 views

Biological key file format

I am in the process of creating biological key software tool for use on android devices. I would like to know if there are any established file formats for storing biological key data. Thanks
2
votes
1answer
201 views

Is Webmedcentral a reputable scientific publisher?

I am a student, and I have written a paper (in drug discovery) which I want to publish. While searching for possible journals I came across Webmedcentral. Is Webmedcentral a reputable scientific ...
5
votes
2answers
87 views

What is the state of automated quantitative analysis?

Quantitative analysis of microscope images is essential for many types of studies, but the techniques used most often are very labor-intensive. I have been able to find some literature about using ...
3
votes
2answers
246 views

variation in antigen binding site of antibodies

Antibodies or immunoglobulins are proteins made ​​by the immune system in response to alien(!) molecules. Each antibody binds to its specific antigen. This great diversity and specificity is cause of ...
1
vote
0answers
31 views

Minimal information about [blank] guidelines [on hold]

The MIBBI and other organizations compile create dozens of "Minimal information about..." guidelines to guide meta-data creation for experimental datasets. These guidelines could/should be adapted to ...
6
votes
1answer
116 views

Do adjacent axons in a nerve influence each other?

Suppose I have a nerve fiber consisting of several axons all running in parallel to each other. When an action potential is generated in a certain axon, this will alter the concentration of sodium ...
2
votes
1answer
116 views

ATP in Glycolysis Vs Gluconeogenesis

In glycolysis, the conversion of glucose to pyruvate results in a net gain of 2ATP molecules. In gluconeogenesis however, the conversion of pyruvate back to glucose requres 6ATP molecules. Why does ...
3
votes
2answers
102 views

How would ecology be affected if 100km² of an ocean surface was covered by a floating object?

Assume that we planted floating solar cells on the ocean surfaces. Assume a 100km² solar cell field in the middle of the Pacific Ocean. All of the sunlight will be blocked by them. How would that ...
4
votes
1answer
114 views

What kinds of arousal can a human brain experience?

I've been reading about the new phenomenon called "arousal addiction". The context in which this term is used is Internet, Porn and/or video game addiction(cummulatively Internet Addiction Disorder - ...
0
votes
0answers
47 views

Why aren't D-amino acids used in proteins? [duplicate]

Possible Duplicate: Why are amino acids in biology homochiral? Why are only L-amino acids used in protein construction, and not D-amino acids?
7
votes
2answers
8k views

At what age do babies begin to synthesize their own antibodies?

When babies are first born, they receive their antibodies from their mother (I assume because they do not yet have the capacity to synthesize their own). So my question is, at what age do babies ...
2
votes
1answer
115 views

Photosynthesis - Light Intensity

Say I was conducting an experiment for photosynthesis. If I moved light closer to the plant, what effect would this have on the process of photosynthesis?
6
votes
1answer
128 views

Cooking with sawdust

In a book about post-war Japan (Embracing Defeat, Dower) the author mentions a process for making sawdust at least partially edible, so it could be used in recipes in a 1:4 ratio with flour for ...
2
votes
1answer
110 views

What is the cannabinoid autoreceptor?

"Is there a cannabinoid autoreceptor? And if so what is the cannabinoid autoreceptor?" (i.e. is the cannabinoid autoreceptor CB1, CB2 or is it one of the G protein coupled receptors, GPR18, GPR55 or ...
4
votes
2answers
293 views

Effects of exercise on the brain

I am well aware of the phenomenon of neurogenesis induced by exercise, as well as the dopamine release that results from exercise. I am really interested in neuropsychology and the effects of exercise ...
-2
votes
2answers
407 views

Why human body cannot defend against HIV? [closed]

Some says that HIV destroy IRF3, and some says HIV overruns T-cells.
5
votes
3answers
280 views

What is the inbreeding coefficient for the female offspring of a sib-mating in a haplodiploid system?

The inbreeding coefficient of a sibling mating for a diploid organism is 0.25 (each allele has a 25% of being identical by descent in the offspring). In haplodiploid organisms, males result from ...
3
votes
3answers
9k views

What type of cell do you start with in Meiosis?

Okay, I was learning about mitosis and meiosis in school and had a question. I know in Mitosis you first start off with a Diploid (2N) cell and then end up with two ...
6
votes
4answers
122 views

Can a tumor produce something not currently found in our own bodies?

While speaking with my co-workers, the topic of tumors growing things came up. The examples were (and backed by images) of tumors growing a tooth, hair, and sometimes even more complex objects such ...
5
votes
1answer
125 views

What is the extent of the effect of Tris on E. coli?

I was a fool and dissolved my antibiotic (Kanamycin) into Tris Buffer rather than H₂O. The Kanamycin still seems to be active but a fellow labmate mentioned that Tris messes around with the membrane ...
2
votes
0answers
39 views

Endocannabinoid Transporters - which ones are Likely to Exist and what is the Evidence for their Respective Existence?

Endocananbinoid = Endogenous Cannabinoid or CB1 and CB2 ligands. I'm asking which endocannabinoid transporters exist and could the one answering show all the evidence for the existence of the ...
3
votes
4answers
860 views

What evolutionary reason is there for having the urinary duct and reproductive organs so close together?

As the old joke goes, "God must have been a civil engineer. Who else would put a waste facility straight through a recreational area?" But maybe it wasn't God. Is there any evolutionary reason (or ...
4
votes
1answer
180 views

How is respiration an unbalanced equation

The equation for respiration is C6H12O6+6O2→6CO2+6H2O+36ATP. The chemical formula for ATP is C10H16N5O13P3. How is this possible, since it violates the law of conservation of mass because it is ...
1
vote
1answer
50 views

Does difference in expected life duration between men and women have biological nature?

It is known that men in most countries live less than women. I wonder whether it is due to different life conditions or because male and female organisms differ? For example, I heard that ...
9
votes
2answers
650 views

Do hormone drugs affect whether a person feels sexual attraction to males or females?

I know that ingesting testosterone and other hormonal drugs may stimulate libido and increase sexual desire. But I wonder, if a man ingests female hormones such as estrogen, will he experience sexual ...
7
votes
3answers
393 views

How can you test what color different people perceive?

If I would show someone a yellow object and ask them, "is this object yellow?" That person would say "yes". But I could never know if my perception of the color yellow is the same as that other ...
4
votes
4answers
5k views

Why are mosquitoes repelled by smoke?

A well known way to have a rest of mosquitoes during camping is to stand in the fire's smoke. Moreover, I learned recently that shepherds in certain regions of Africa use the same tactic for cattle. ...
4
votes
1answer
41 views

position of cell penetrating peptide

I'd like to add a cell penetrating peptide to my custom peptide (30aa). Can I just add it to the end of the peptide sequence or does it have to be positioned on an outward facing external chain?
13
votes
2answers
6k views

Why do people have antibodies against other blood types?

The ABO blood type divides each blood type according to whether they have the "A" and "B" antigen(s) (AB has both, O has none). People also have antibodies against the antigens they don't have (AB has ...
4
votes
1answer
599 views

What causes Acne?

What exactly is going on biologically at the molecular level with acne and causes breakouts? Hormonally, there is a lot going on but I'm curious about what is going on chemically.
2
votes
1answer
31 views

What signals histone methyl transferases to function?

I wanted to find out if anyone knows what stimulates histone methyltransferases to function? I know that it is a process still trying to be understood, but I can't find anything that seems to direct ...
1
vote
1answer
542 views

Breathing water vapour

Normal air consist of oxygen, CO₂ and nitrogen, with traces of water etc. Now imagine displacing all gasses except oxygen with water vapour. By water vapour I don't mean hot steam or fog. Just ...
4
votes
1answer
373 views

Why do we squint?

Recently, I was having an eye exam and admitted to squinting my eyes to sharpen blurred edges. Later, while waiting for the dilation to set in, my brother (a would-be pharmacist fresh off an anatomy ...
3
votes
1answer
80 views

Regeneration capabilities in humans?

To what extent can humans, (mammals in general), theoretically regenerate, and is their a way to speed up and/or exceed this original extent.
4
votes
1answer
78 views

Is it possible to purify antigens from a vaccine and to separate them from the adjuvant?

I need to separate the antigens from several vaccines in order to use them for coating microplates to run an indirect ELISA. I at least need to remove the adjuvant from the vaccines. Is this possible ...
6
votes
2answers
9k views

Can positive and negative blood type of a couple lead to miscarriage?

I want to know can $+ve$ and $-ve$ blood group of a couple could be a cause of miscarriage in pregnancy?
1
vote
1answer
823 views

What is the difference between average and monoisotopic mass calculations of peptides?

I often have to calculate the mass of peptide sequences using calculators such as here. I have the option of calculating the average and monoisotopic mass, but what is the difference?
5
votes
2answers
1k views

Do octopuses have better eyes than humans?

I've read that unlike humans, octopuses have eyes "designed" the "right way", i.e. with the nerve fibers behind the retina, thus getting rid of the blind spot we humans have as well as theoretically ...
4
votes
1answer
307 views

Why are eggs “egg” shaped?

Is there a reason as to why chickens lay "egg" shaped eggs, as opposed to spherically shaped eggs (or a random shape)? <--- Main Question For extra points (actually just to add more words in ...
2
votes
1answer
6k views

Why are bacteria and archaea in different domains?

As I understand it, the main difference between the Bacteria and the Eucaryota domains are that eukaryotes have a nucleus and bacteria don't. I understand that bacteria and archaebacteria have enough ...
1
vote
0answers
27 views

Does regulate always mean suppress when it comes to heteroreceptors?

Do heteroreceptors always suppress the release of the neurotransmitter they regulate upon their (the heteroreceptor's) activation?
4
votes
1answer
62 views

Parsimony (cladistics)

I don't understand how to sum the changes in a phylogenetic tree. Here for example: http://www.med.nyu.edu/rcr/rcr/course/phylo-cladistic.html How do you end up with 8 for the first and 9 for the ...
4
votes
2answers
55 views

Cell cycle selection

Is it possible to select from colonies only cells which are at a certain stage in the cell cycle? E.g. if I was trying to analyse expression of a number of genes during different stages of the cell ...
8
votes
1answer
10k views

What is the composition of human feces?

Are there any studies or general information on the composition of human feces? I'd specifically like to know the percentage of carbohydrates and amino acids relative to the amount that was ingested ...

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