4
votes
1answer
1k views

How does prolonged exposure to high frequency noise affect hearing?

Is there any research showing how prolonged exposure to background noises, particularly high frequency noises, affect hearing abilities? Does constant high pitched noise cause damage even a low ...
2
votes
1answer
61 views

Historical recovery from mass extinction events

Is there a way to generally characterize how species "regrew" after the various mass extinction events happening periodically from 450 Ma to 65 Ma. Would the surviving species just start back where ...
2
votes
1answer
620 views

Does coloring affect the perception of depth?

I have a question about the mechanics of human vision which may be as much of a physics question as it is a biology/physiology question. I noticed that if I try to imagine a clear blue daytime sky ...
3
votes
1answer
202 views

How do multiple replication forks function without 'colliding', and what is the benefit of this method?

I'm currently reading a little about DNA replication, and have come accross the following statement; Replication starts from a fixed point and is bi-directional ... In Eukaryotes, there are ...
2
votes
2answers
1k views

Do T-cells express MHC molecules?

T-cells recognize the MHC molecules and body's own peptides. When it doesn't, it alarms the immune system. But do T-cells express MHC molecules ? If so, how are they using it? If not, what happens ...
3
votes
1answer
67 views

Would ovoviparous to viviparous mutation have been gradual? How would that work?

It seems unlikely that an ovoviparous ancestor of mammals long ago could have had a viviparous offspring in a sharp one-generation dividing line, but what would be the gradual steps between egg birth ...
6
votes
1answer
160 views

Why does not the host produce any immune response to antiserum antibodies?

When an antiserum is injected to a person to protect oneself from a certain disease, the antibodies in the antiserum come from another organism. The question is: Why don't the injected antibodies ...
1
vote
1answer
138 views

Cine-MRI versus MRI

Could someone explain the difference between Cine-MRI and MRI? I am reading conflicting things online, such as Cine-MRI uses ECG-gating, or that Cine-MRI takes many images of the same position of the ...
2
votes
2answers
103 views

Can a new Y-chromosome be created?

The major gene of the Y-chromosome is SRY. Would it be possible to get the X-chromosome and add SRY to create a "fuller" Y-chromosome? What advantage does the skinny Y-chromosome give an individual ...
1
vote
1answer
96 views

Interlocus Contest Evolution means suicide?

I was reading Matt Ridley's "Genome" book. I am trying to understand the Interlocus Contest Evolution in his X-Y chapter. I do not understand why the X and Y chromosome would want to kill each other. ...
2
votes
0answers
35 views

Is there an entry-level circadian model of serotonin, ghrelin, dopamine and the sense of well being?

I've long been interested in circadian rhythms and recently came across a variety of articles that appear to indicate that the following neurotransmitters, transferases and hormones are connected. ...
6
votes
2answers
536 views

Does body temperature affect human lifespan?

If a human body were somehow to be kept at a cold temperature (say 30C) for the entire life of the given individual. And somehow the brain could be fooled into thinking that this 30C feels nice and ...
2
votes
1answer
232 views

Temperature Tolerance In Relationship To Body Temperature

A humans body temperature averages at around 98.6°F A dog's body temperature averages at around 101.5°F If the temperature ...
3
votes
3answers
840 views

Why does the apex of the human heart usually point to the left?

In the majority of human beings, the apex of the heart (left ventricle) points towards the left side of the body. Sometimes however (approx. 1/12000 births), a person is born with a condition known ...
10
votes
2answers
164 views

Have any genetically altered organisms actually become abundant in a natural environment?

Most of the things that come up in Google and Google Scholar for this question have a mostly/completely speculative tone, or at best use models instead of measurements. This report describes some ...
1
vote
0answers
41 views

Can viral proteins cause infection? [duplicate]

Possible Duplicate: HIV Rapid Tests Can proteins found on the surface of RNA viruses cause infection without the presence of the actual RNA and other components used in the virus?
3
votes
1answer
219 views

Are there records of monozygotic twins in which one experiences androgen insensitivity syndrome

I have given my high school biology students the thought experiment of "What would happen if a researcher induced twinning of a female zygote and then replaced one of the X Chromosomes with a copy of ...
2
votes
1answer
75 views

Difference In Telomeres Between A Thale Cress Plant And A Methuselah Tree

From what I have read and understood telomeres cap off how many times a cell can divide before it can no longer divide and that is what causes aging. A thale cress plant apparently has a life cycle ...
17
votes
2answers
666 views

Why Is Most Life Symmetrical Externally But Not Internally?

Mammals, reptiles, arachnids, insects, etc are all as far as I am aware symmetrical in appearance. Take a human for instance, make a line from the top of our head right down the middle. However, ...
3
votes
3answers
159 views

Are there people cured of HIV by means of HAART?

I wonder if there people who were cured of HIV only by means of highly active anti retro-viral therapy (HAART) or other drugs rather than by bone marrow transplant? I know that HAART can suppress HIV ...
1
vote
0answers
59 views

Why do people feel extreme cold at different temperatures compared to other people of same body structure?

I have seen some people shivering in the room temperature of 18°C while others of similar body structure do not feel that much amount of cold. Of course the clothing of both people is similar if ...
1
vote
0answers
47 views

Solid phase use in HIV rapid tests

I have another question in regards to my HIV test research. The rapid tests like Orasures Oraquick contains a strip of synthetic peptides that are used to represent proteins found in the envelope ...
1
vote
1answer
43 views

Can gelatine digestion make blood more thick?

Can gelatine cause blood thickening if digested?
7
votes
1answer
145 views

Why Can't A Male Mule Have Offspring?

I've read that female mules can sometimes have offspring, but that male mules are incapable of doing so. Why is that the case? Is their sperm not capable of entering the egg or is their a genetic ...
2
votes
0answers
87 views

In scuba diving, are nitrogen narcosis and high pressure nervous syndrome the same thing?

In training for scuba diving, they tell you that when you're bellow 100 ft or so you have to watch out for changes in mental state that resemble drunkenness. The cause of these mental disturbances is ...
2
votes
0answers
54 views

Can frequent ultrasound diagnostics be harmful?

Are there any short or long term effects apparent in tissues if a zone (or the whole) of human body is scanned with ultrasonic waves often?
5
votes
2answers
3k views

Why can't you taste food when you have a cold?

It is a common observation that food is tasteless when we have a cold. Why is that so? What is the cause of inability to taste when we have a cold? Are the nose and ability to taste connected?
3
votes
2answers
437 views

Physiological indicators of happiness and well being

If I understand it correctly, levels of serotonin in the brain can indicate if a person is happy. What other physiological measures indicate happiness or well being for a humans? I am looking for ...
3
votes
0answers
19 views

Does Doxylamine have any Influence on the Monoaminergic System?

Does doxylamine have any affects on the monoaminergic system? Specifically I am interested in adrenergic or serotonergic activity but additional information on its dopaminergic activity won't hurt ...
5
votes
2answers
135 views

HIV Rapid Tests

The hiv antigens that are used in the oral rapid tests, are they infectious? The tests do not contain any actual virus but I am curious if the antigens themselves could somehow create the virus on ...
6
votes
3answers
3k views

How do warm-blooded animals keep their temperatures constant?

Warm blooded animals like us keep their temperature constant irrespective of their surroundings. But how do they do that? Energy should be supplied from the inside. I assume that reactions like making ...
2
votes
1answer
56 views

Which Enzymes are Responsible for the Biodegradation of Noladin Ether?

Which enzymes degrade the CB1-specific endogenous cannabinoid 2-arachidonyl glyceryl ether? (Noladin ether)
3
votes
1answer
480 views

Chromosome 2 fusion?

I read this article by Jeffrey Tomkins and Jerry Bergman claiming to debunk chromosome 2 fusion. Is there anything wrong with these conclusions? " 1.The reputed fusion site is located in a ...
2
votes
1answer
30 views

Which Enzymes are Responsible for the Biodegradation of Beta-endorphin?

Which enzymes are responsible for the biodegradation of the endogenous opioid peptide, beta-endorphin?
4
votes
1answer
90 views

Are serotonin levels in humans affected by light?

I'm reading this Wikipedia article on light therapy and noticed a peculiar statement: The production of the hormone melatonin, a sleep regulator, is inhibited by light and permitted by darkness ...
1
vote
0answers
89 views

What are the biomarkers for autoimmune diseases? Significancy, related diseases, detecting mechanisms

I think this is a trick question, since to understand what are the biomarkers we need to understand what are the encoding genes that make the antibodies. Then, I would explain the reason why to ...
3
votes
2answers
68 views

What chemical or biochemical agents do plants use to inhibit each other's growth?

As I just learned, allelopathy is the action by which plants regulate the growth of other nearby plants. I have hear of ethylene is a general signal for growth and fruit ripening in particular, but ...
1
vote
0answers
15 views

What are studies linking dietary choices over life with probability of reaching higher ages?

Are there big studies that link diet and lifestyle choices with the probability of reaching a certain age? What are their conclusions?
-2
votes
1answer
79 views

Good place to ask health based questions? [closed]

I like the development of biology.stackexchange.com, but it is still in an early stage and far from perfection. While we develop it further, could you guys help me finding places to ask questions ...
2
votes
1answer
61 views

Are humans hardwired to continue gathering resources after the costs outweigh the benefits?

An animal will stop foraging in a berry bush if the perceived cost of searching for berries remaining is greater than the cost of finding another bush which isn't as picked over. People do the same ...
3
votes
1answer
175 views

Questions regarding ELISA

I have recently peformed an ELISA (Enzyme-linked immunosorbent assay), but I still have some questions, let me first outline what I did: We had a number (20) of tubes containing fake 'bodily fluids' ...
6
votes
2answers
192 views

How do infectious bacteria know when their numbers are high enough to attack a host?

When you get sick, you generally don't contract enough bacteria at once for them to succeed in battling your immune system, right? Their numbers must gradually increase in the host's body before they ...
6
votes
1answer
137 views

Is there a normal human melatonin concentration to light level curve?

I'm looking for a graph or a curve that would show the typical concentration of melatonin in blood or saliva for humans over 24 hours. It would be good to know the photoperiod for the same human as ...
2
votes
2answers
95 views

Possibility of orthogonal view for a creature?

Just a pure curiosity: Does there exist a creature with an orthogonal view to the world instead of perspective? What would be an optical explanation for possibility/impossibility?
2
votes
1answer
70 views

Do plant-plant interactions inhibit growth?

Plants produce lots of compounds that inhibit (kill or irritate) microorganisms and insects. They have defenses against plant viruses and infections. What kinds of compounds or hormones to plants ...
13
votes
2answers
319 views

Evolution in 37 years, is it possible?

I am confused, can evolution ( speciation ) really occur in such a short time ? In 1971, biologists moved five adult pairs of Italian wall lizards from their home island of Pod Kopiste, in the ...
5
votes
1answer
44 views

Can paper/plastic currency serve as a medium for pathogens?

http://www.nytimes.com/2009/12/15/health/15real.html seems to indicate for a surface, to serve as a medium, the following properties are relevant animation humidity temperature The article ...
12
votes
2answers
1k views

How many people are required to maintain genetic diversity?

Imagine humans were to colonize a distant planet and it was a single one-way trip. How many people would they need to bring? Obviously 2 is the minimum, but that would result in a lot of inbreeding. ...
2
votes
1answer
146 views

Can Taq polymerase be used instead of polymerase Vent exo (-)?

Instead of using polymerase Vent exo (-), can I go with the usual Taq polymerase? Do the PCR conditions change (the temperature and master mix concentrations ) in the these two conditions? Do the ...
1
vote
0answers
137 views

What are the tissues affected by thyroid hormone called?

I found this question and I wonder if it is asking some general name where both T3 and T4 have an effect. I cannot find any such single name. Is there any single name of tissues that are affected ...

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