3
votes
3answers
121 views

why do some cells in the body prefer necrosis to apoptosis as a means of cell death?

There are many programmed cell death pathways, but some cells show a greater preference for some over the other. I'm wondering as to why if necrosis is an inflammatory response that causes damage to ...
3
votes
1answer
89 views

How to inhibit formation of specific antibodies (to antisera)?

Is there a way to inhibit an antibody response to a specific antigen using immunosupression? I am interested in reducing the anti-antibody formation to animal antibodies such as murine antibodies in ...
3
votes
0answers
94 views

What proportion of salt in water would make it not dehydrate nor hydrate someone? [duplicate]

Drinking sea water can be deadly as it contains too much salt, basically de-hydrating the body. Normal tap water contains little salt and is good for re-hydration. My question: How much salt needs to ...
3
votes
3answers
509 views

Why does a cockroach not die even after decapitation?

Why does a cockroach not die after its head is cut off?
3
votes
2answers
185 views

How did aquatic dinosaurs go extinct?

Dominant theory is that 'normal' dinosaurs went extinct from ether super volcano or meteor impact or combination of both. However there were aquatic dinosaurs that are not present at this day. Was it ...
3
votes
1answer
60 views

Mechanisms of bone growth

The length of a bone is caused by growth of hyaline cartilage which is then replaced by bone tissue. How do cells know whether they should grow the hyaline cartilage? What are the key molecules that ...
3
votes
2answers
63 views

What is an Ihh-/- mouse?

This one is too basic question: I just came across $Ihh^{-/-}\ $ mouse. Is that means this mouse devoid of that gene Ihh. What is this sign called and are there other such representations?
3
votes
2answers
424 views

In practice, do fishes die from old age?

I was watching sea birds eating fishes and wondered if fishes actually died from old age, or if they are all eaten before this can happen? I reckon some big predator fishes must be able to live long ...
3
votes
1answer
192 views

Cicada Killer Behavior

I've had a giant wasp hanging around outside my window the past few days, so I've resolved to learn more about it. I believe it is a male Cicada Killer, because it displays the following behavior: ...
3
votes
1answer
296 views

Where do butterflies sleep?

Do butterflies (insects) sleep, and if so, where?? I have googled for information but didn't get an exact answer.
3
votes
3answers
128 views

Does a reduction in stem cells mean possible earlier death?

The basis of this question relies on my understanding of these 2 facts: ...
3
votes
1answer
94 views

Inbreeding depression and dominance

From this article, second paragraph of the second page A classic theoretical result is that the mean of a character controlled by a single locus i with two alleles Ai1 and Ai2 is only affected by ...
3
votes
0answers
51 views

Inbreeding Coefficient and Coefficient of Relationship

Wikipedia gives the following formula to calculate a "path of coefficient of relationship" between an ancestor $A$ and an offspring $O$: $$\rho_{AO} = 2^{-n} \left( \frac{1+f_A}{1+f_O} \right)^{1/2} ...
3
votes
1answer
528 views

Why do cockroaches burst from soapy water?

(careful, disturbing!) I was experimenting with some stray cockroaches that ended up falling in my bath tub overnight (there is currently an infestation undergoing in my apartment building) and I ...
3
votes
1answer
716 views

Death by exsanguination not painful?

Several places on the internet seem to purport that animal sacrifice is painless because exsanguination causes no pain. That sounds unscientific to me and an attempt to appease culture than than using ...
3
votes
1answer
122 views

Why insects are so small compared to mammals?

I was wondering what biological limitations make the dimension of the insects small compared to the dimension of the mammals. I know in other eras insect were bigger!
3
votes
1answer
495 views

What is needed for a G-matrix?

I have been doing a lot of reading on quantitative genetics and the G- (and B-) matrix lately. I get the principle behind performing the analysis now but I am still not sure how to do it. I'd like to ...
3
votes
1answer
479 views

What hair color will result in someone inheriting both blond and ginger genes?

Both the genes for blond hair and ginger hair are recessive, so they need both parents to give the same gene for it to take affect. What happens when a person has 1 copy of a recessive gene and ...
3
votes
1answer
386 views

Is there a difference between pig and cow anatomy that makes religious slaughter of the latter less painful?

This question is not for the squeamish. I was told that non-Kosher animals like pigs have a different anatomy in their neck compared to kosher animals like cows such that the Shechita method of ...
3
votes
1answer
293 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, ...
3
votes
1answer
217 views

Does an allergic reaction kill body cells?

I have wondered what actually happens in an allergic reaction that causes the symptoms such as pain, rash etc. Is it possible that the human body actually kills its own cells in the process?
3
votes
4answers
797 views

Which came first: The Chicken or the Egg? [closed]

Has there been any serious scientific inquiries into answering this age old question?
2
votes
1answer
57 views

Markers for human genetic mapping

For human genetic mapping several different types of markers are used: RFLPs (Restriction Fragment Length Polymorphisms) VNTRs (Variable Number of Tandem Repeats) such as mini- and microsatellites ...
2
votes
2answers
192 views

What is the minimum eye?

What is the minimum eye which confers some evolutionary advantage? By minimum I mean anything less than this has no advantage whatsoever and therefore is not favored by natural selection. By eye, I ...
2
votes
2answers
291 views

How can we know or measure pain in animals?

Is there any standard way to know how much pain an animal feels when it gets hurt like when a bird loses it's wing or hen when killed etc. All pain sensation points? Hey I'm new to biology. :)
2
votes
1answer
76 views

Identification of unknown bagworm (Singapore)

This bagworm was found in Singapore (near McRitchie Reservoir) some time in June 2012. This is the plant from which the bagworms were obtained: A few examples of the bagworms: The bagworm when ...
2
votes
1answer
75 views

What are the requirements for a spectrometer to be used in biological research?

Suppose one would do spectrophotometry on biological materials. What would be the minimum requirements for the measuring device so that the results could be published in a reputable journal? I suppose ...
2
votes
1answer
83 views

How was Restriction Site of EcoRI sequenced?

The sequence of restriction site of EcoRI - GAATTC was identified in the early 1970s, before Sanger Sequencing was invented.(1977) How was the restriction site of EcoRI sequenced ?
2
votes
3answers
384 views

Why cancer mutations do accumulate sequentially?

According to Knudson hypothesis, cancer mutations accumulate in order. Statistics says, that cancer probability increases as sixth order of age, which may mean six consequential steps to cancer. But, ...
2
votes
1answer
246 views

What is the cause of dry cough?

I first thought this question in the case of the cause of dry throat after 3-day recovery of dry cough? but then I realised that the cause of dry cough can be a general thing. Assume the person ...
2
votes
1answer
49 views

How are new chromosomes replicated into the next generation via sexual reproduction?

If an individual has a new chromosome, which is very unlikely to happen, he will not have any luck in finding a sexual partner with this same trait. How will the offspring inherit this trait. And ...
2
votes
2answers
531 views

How did the first sexual animal come to exist? [closed]

I am more or less familiar with the evolution theory based on mutations. Now, starting with a nonsexual being, how did the first organism that reproduces sexually come to exist.
2
votes
1answer
1k views

How many species have existed on earth? [duplicate]

I found a paper estimating the number of species currently living on earth. Now I'm wondering If anybody tried to estimate the number of species that have lived on earth. I'm familiar with problems of ...
2
votes
1answer
87 views

How many different smells can a human recognize?

How many different smells can a human recognize? If the space of smells is not discrete, how many dimensions it has (for example, the space of colors is three-dimensional).
2
votes
1answer
81 views

What happens during a Raynauds episode?

Raynaud's phenomenon can be a serious health issue, as the blood flow to the extremities, mainly the fingers is compromised, causing fingers to blanche, and then turn blue. Severe Raynaud's can cause ...
2
votes
3answers
149 views

Why are things conscious?

I've been referred to here from http://philosophy.stackexchange.com/questions/8052/why-are-things-conscious. Could you guys help out? Here's the question: What is the reason for animals or more ...
2
votes
1answer
51 views

How can a respiratory infection lead to a skin infection?

Example of a case: 5 children develop a bright red rash on the face and turns violet after a few days and then disappears. Then maculopapular rash appears on the trunk, buttocks and extremities. It ...
2
votes
1answer
235 views

What is the difference between vegetable and fruit?

Is there any exact definition of vegetable and fruit? How can new plant be classified?
2
votes
2answers
1k views

What is in the space between neurons in a brain?

When neuron animations are displayed, there are frequently seen neurons, axons arranged in a lattice with a lot of empty space between. I'm interested if there is indeed empty space in the brain, or ...
2
votes
0answers
43 views

How much does a human brain's metabolic rate vary? [duplicate]

Possible Duplicate: How does brain energy consumption depend on mental activity? Our brains consume about 20% of our energy when we're at rest. How variable is a human brain's energy ...
1
vote
1answer
118 views

What is the relationship between radiation and evolution?

There is always a certain amount of background radiation present, for example due to ionizing radiation from the sun and other stars. Also certain materials like granite may emit relatively large ...
1
vote
1answer
64 views

Modeling intracellular interactions between sender and receiver bacteria

I am involved in a modelling task of a biological process described as follows: -- "Objective: to model behavior of a sender receiver type system The process goes as follows Pre-signal [PS] is in ...
1
vote
0answers
59 views

What good is the MinION?

This year, Oxford Nanopore MinION has been shipped to some researchers for testing. The advantage of a table-top sequencer for diagnostics and personalized medicine is obvious. Similarly, research ...
1
vote
1answer
63 views

Gastro-intestinal physiology reference

I am a physicist but I have always wanted to understand how my digestion takes place in as much detail as possible. I have no idea about books or reference on the subject of Gastro-intestinal and ...
1
vote
1answer
175 views

What is the effect of Montelukast on the amount of IgE in blood?

I know that it decreases the amount of leucotrienes in blood. I saw a patient with high IgE altough under Montelukast medication. This suggests me that Montelukast does not affect the immunoglobulins, ...
1
vote
0answers
158 views

Effects of Genetic Drift on Linkage Disequilibrium

From what I understood of @Canadianer's answer here... Genetic drift randomly causes negative or positive linkage disequilibria, by changing allele frequencies through random sampling. Natural ...
1
vote
2answers
99 views

Effect on fitness of mutations

What is the distribution/probability density function (PDF) of impacts on fitness of new mutations? I very welcome any partial answer that does not give the whole PDF but just some information ...
1
vote
1answer
39 views

Dominance/recessivity of new mutations

What is the distribution/probability density function (PDF) of recessivity/dominance of new mutations? I very welcome any partial answer that does not give the whole PDF but just some information ...
1
vote
8answers
644 views

How does the creative process of Biological Evolution work?

In order for nature to go from microbes to man, there needs to be new information. Where does this new information come from? It is understood that Evolution basically involves three elements. ...
1
vote
1answer
146 views

How to relate human metabolic model reactions and cancer drug targets / reactome items?

Trying to find a way to take a cancer drug (from CancerDR, for instance) and infer the metabolic reactions that are affected by it in the Human Metabolic Model. Essentially, I would like to know ...

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