0
votes
1answer
67 views

Static in limbs

I have noticed that while sitting in the Sukhasan posture(picture below) for a long time, my feet suddenly become all stiff and i am unable to move it. What I deduce from the experience is that it is ...
0
votes
2answers
1k views

Will I grow taller? How can i tell? [closed]

I'm 17 and I'm about 160 cm and my weight is 47 kg . I just want to know if I will still grow taller ?
0
votes
1answer
58 views

Is forced cell growth related to apoptosis?

Could an instance of forced cellular growth cause some cells to have their self-destruct mechanisms to malfunction or 'turn off'thus preventing apoptosis?
0
votes
1answer
393 views

What's the difference between life expectancy of cigarette smoker and general population?

Some say that smoking cigarettes will shorten lifespan. By how many years is the lifespan of a typical smoker shortened? What are the common cause(s) of death among smokers? Are there any known ...
-1
votes
2answers
240 views

Can you answer Ray Comfort's question on Biological Evolution? [closed]

https://www.youtube.com/watch?v=U0u3-2CGOMQ There's this video on Youtube about biological Evolution that has gone viral. I'll paste it above for your convenience. To cut to the chase, Ray Comfort ...
67
votes
2answers
2k views

How many times did life emerge from the ocean?

Evolution is often mistakenly depicted as linear in popular culture. One main feature of this depiction in popular culture, but even in science popularisation, is that some ocean-dwelling animal sheds ...
35
votes
4answers
3k views

Life without DNA?

I'm by no means an expert in the field, merely a curious visitor, but I've been thinking about this and Google isn't of much help. Do we know of any lifeforms that don't have the conventional ...
32
votes
4answers
1k views

Can scientists create totally synthetic life?

This particular question has been of a great deal of interest to me, especially since it dives at the heart of abiogenesis.
33
votes
1answer
13k views

Why Does Salt Water Help Sore Throats?

I am having some trouble understanding how salt water, a simple solution, could so effectively remove the pains of a sore throat. I do believe that the answer is closely related to hypo/hyper-tonic ...
15
votes
2answers
5k views

How do the brain and nerves create electrical pulses?

I have heard that information is sent between the brain and peripheral nerves via electrical pulses or signals, but I don't understand how they create them in the first place.
25
votes
1answer
3k views

What causes morning wood?

Sometimes men wake up with an erection in the morning. Why does this happen?
14
votes
8answers
7k views

Why have humans evolved much more quickly than other animals?

Humans have, in a relatively short amount of time, evolved from apes on the African plains to upright brainiacs with nukes, computers, and space travel. Meanwhile, a lion is still a lion and a ...
14
votes
3answers
508 views

What is the most difficult feature to explain evolutionarily? [closed]

I wonder what are examples of organs/structures/behaviours/cooperation that evolutionary biologists themselves find most difficult to explain -- to explain how they could appear evolutionarily -- ...
13
votes
4answers
2k views

Why is the Hydra Biologically Immortal?

I have heard that the Hydra organism is biologically immortal (later I found that there are more immortal organisms). Now I know that its immortality is related to its telomerase. The thing is that we ...
13
votes
1answer
454 views

What light intensity starts melatonin release in humans?

I'm interested in whether any studies have determined the intensity of light at eye level that starts melatonin release in humans. I know that: melatonin release is suppressed by blue light with ...
13
votes
1answer
746 views

Are human bodies programmed to die?

Following from this question: What is the evolutionary advantage of death?: Is there any evidence that human bodies have systemic self-destruction built into their developmental program? I'm not ...
12
votes
10answers
848 views

A good book for history of biology/biotechnology for lay people

I have many friends who are interested in Biology and want to know more about the subject in general (like a history of biology, from Darwin's theory, to DNA structure discovery, to the human genome ...
11
votes
1answer
433 views

Supercomputer Vs Human Brain

With supercomputers doing calculation in petaflops ($10^{15}$ Calculations per Second), have we crossed the speed of Human Brain?
10
votes
1answer
152 views

Does stress physically age our body?

Going by the assumption that stress eventually triggers a flight/fight response, and the subsequent realization that flight/fight puts the body in a system of readiness to use it's available resources ...
8
votes
2answers
280 views

What does fitness really mean?

Fitness is certainly the most important concept in the theory of evolution. My question does not have to do with practical measures of fitness but with the theoretical definition of it. I am a bit ...
7
votes
1answer
225 views

On average how many genes / alleles do people share?

I am curious about how much more a child can be alike to one parent than the other. If a child were to inherit all the alleles that are shared between both parents from one parent, but inherit all ...
6
votes
2answers
104 views

How are Genetic Circuits Modelled?

I've read a recent Nature Methods paper by Moon T.S. et al, in which a synthetic genetic circuit consisting of layered logic gates was created. For example, the paper, a circuit is modelled in Figure ...
30
votes
2answers
1k views

How do cockroaches resist the effects of ionizing radiation?

Cockroaches are very hardy insects. It is known that, among other things, they are able to withstand bursts of ionizing radiation that would kill a human being. The explanations of this observed ...
28
votes
1answer
631 views

What is itching?

What exactly at the molecular level is itching? What physiological function does itching serve, if any? I cant remember the reference but a PLCb3 null mice lost the itch phenotype, so presumably it is ...
19
votes
1answer
249 views

Evolutionary origin and exogenous cues of ~28 day infradian rhythm?

The most obvious example of an approximately monthly biological cycle is the human menstrual cycle. My questions are the following: Is it known when and where this cycle or one like it arose? What ...
18
votes
1answer
2k views

What is the criticality of the ribosome binding site relative to the start codon in prokaryotic translation?

In prokaryotic translation, how critical for efficient translation is the location of the ribosome binding site, relative to the start codon? Ideally, it is supposed to be -7b away from the start. ...
17
votes
5answers
3k views

Why do the two hemispheres of the brain control the opposite sides of the body?

Why does the left hemisphere control the right and the right hemisphere control the left? I googled it but didn't find a good answer regarding this. Could someone explain? Does this adaptation help ...
16
votes
3answers
275 views

How is the blood volume of a living organism measured without killing it?

How is the blood-volume of an organism measured without killing it? NOTE: The blood-volume of an organism is defined as the total volume of blood present inside that organism.
14
votes
4answers
2k views

Height and natural selection in humans?

I watched the documentary "Evolve" recently and in the segment on "size" Scott V. Edwards, Harvard evolutionary biologist mentioned the idea that humans might evolve to be 7' tall in 'hundreds of ...
12
votes
3answers
152 views

How are long time periods measured in biological systems?

Biological systems are pretty good at measuring fairly long times, for example, menstrual cycles (month), or puberty (years). Counting days or years seems to be implausible, and chemical concentration ...
11
votes
1answer
221 views

Do fake wasp nests actually fool wasps?

I have seen fake wasp nests sold as a deterrent against wasps and similar insects. Do they really work? Is there some scientific evidence for it? A related link: ...
10
votes
1answer
165 views

What are the functions of magnetic bacteria?

I'm trying to understand why are bacteria "equipped" with magnetosomes and why/what for do they need such organelles.
9
votes
2answers
308 views

How does the genetic code evolve?

After looking at this question, some other questions poped in my mind. The DNA code is redundant, there are 20 amino acids for 64 possible nucleotide combinations. Therefore some amino acid are coded ...
9
votes
1answer
271 views

When does weak selection produce qualitatively different results from strong selection?

In evolutionary game theory, it is typical to model organisms as having a base fitness that is modified slightly by the game interaction. The ratio of the game effect versus the base fitness ...
8
votes
1answer
908 views

Disadvantages of unihemispheric sleep

Is is well known fact that marine mammals and some birds can sleep with one brain hemisphere at a time, since it's essential for their survival. However, at least in my opinion, such mechanism would ...
5
votes
1answer
80 views

Hill-Roberston effects and effective population size

From this article, first page, middle of the second column: Even if harmful alleles do not become fixed, they can still reduce the efficacy of selection on neighbouring loci through a process ...
5
votes
1answer
412 views

Smallest unit on which selection can act

Traditionally, the individual was considered to be the smallest unit on which Natural Selection (NS) acts. Today, we usually consider the gene as being the unit of NS. Of course, we should also ...
4
votes
1answer
137 views

How does “inheritance of methylation” of DNA and/or histones work?

What are the current models/ideas describing the mechanisms explaining inheritance of methylation on DNA resp. histone level? Is there evidance of this "setup" information being really ...
30
votes
4answers
671 views

How does the sensitive plant detect vibrations?

The sensitive plant (Mimosa pudica) is a remarkable little plant whose characteristic feature is its ability to droop its leaves when disturbed: Apparently, this ability to droop rests on the cells ...
25
votes
7answers
406 views

Has there been any observation of species adapting the evolution process?

I am very interested in the evolution of the evolution process itself. There are of course a lot of things that influence how evolution will work, but for this question, I am interested in things that ...
24
votes
3answers
7k views

Why do eukaryotic organisms have introns in their DNA?

We touched on introns and exons in my bio class, but unfortunately we didn't really talk about why Eukaryotes have introns. It would seem they would have to have some purpose since prokaryotes do not ...
20
votes
1answer
475 views

How, on a physical level, does ATP confer energy?

When ATP is used as the energy currency to make, say, reaction X + Y → Z happen, is what happens on a physical level down at the molecular scale that during the reaction ATP + H2O → ADP + Pi ...
18
votes
3answers
19k views

If the brain has no pain receptors, how come you can get a headache?

I've read many years ago in books, that the brain has no nerves on it, and if someone was touching your brain, you couldn't feel a thing. Just two days before now, I had a very bad migraine, due to a ...
17
votes
4answers
2k views

Why are there species instead of a continuum of various animals?

As I understand it, various animal traits have to evolve gradually, but what happens to the species that are "neither here nor there"? To put it differently, if a species evolved from another, it did ...
16
votes
3answers
1k views

How and where, in the human brain, are memories stored?

Background I am a computer programmer who is fascinated by artificial intelligence and artificial neural networks, and I am becoming more curious about how biological neural networks work. Context ...
15
votes
2answers
3k views

Why is glucose our primary source of energy?

Is there any evolutionary reason for glucose being the "main" molecule used as a source of energy, beginning with glycolysis and subsequently cellular respiration (after being converted to two ...
15
votes
3answers
419 views

Why do some trees have a life span, while some don't?

I have heard that there is no limit on the growth of trees, but then why do some trees, such as boxelders and poplars, tend to live shorter than redwoods, for example? Some advertisements for improved ...
14
votes
2answers
843 views

Why is 'Grudger' an evolutionary stable strategy?

I am currently reading 'The Selfish Gene' by Richard Dawkins, which I am sure many here have read. The topic are evolutionary stable strategies (ESS) regarding cooperation. I apologise for the long ...
14
votes
3answers
379 views

Are human fetuses more likely to be male?

Question: From a physiological point of view, when sex is determined in a human fetus, is it equally likely to be male or female? Studies in this area typically measure age at birth, where the data ...
14
votes
1answer
1k views

Why do some mammals not have testes in a scrotum?

Coming from an evolutionary approach, Is the only purpose of a scrotum to regulate the temperature of the testes? Knowing all mammals are warm blooded, shouldn't all mammals have testes in a ...

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