1
vote
1answer
99 views

Is “Fight or Flight” distance genetic

If you took a newborn animal and completely isolated it from its species, would it be capable of assuming a fight or flight distance preset by its species, due to their being no basis for what could ...
2
votes
1answer
722 views

Do body lotions enter into bloodstream of people? And how do they do it?

I found this very disturbing: bombastic tabloid-style writing in capital and the content is doubtful. If it was correct or close "does it really take something like 26 seconds for a body lotion ...
1
vote
0answers
25 views

Effect of applying fungicide to a field [closed]

What would happen if we apply fungicide to a corn field , would the Net Energy Production increase or decrease ?
4
votes
1answer
92 views

What triggers DNA to produce proteins?

What is the trigger for DNA to produce proteins or RNA? I have found enough material to study the inner workings of the cell and DNA; but, I can't find an explanation of the mechanics the cell uses ...
0
votes
1answer
136 views

All or none phenomenon

Let's say that the threshold potential of a neuron is +40 mV to make a muscle twitch. Now suppose we have two signals of +20 mV. So, this signal will cause the twitch in muscle because it has reached ...
0
votes
1answer
74 views

Non toxic low melting point alloy

I am looking for an alloy with low melting temperature (< 350°C) which is not toxic when in direct constant contact with skin, food and overall in domestic environment. My application is a solder ...
1
vote
1answer
71 views

Botulinum Toxin

I asked on the cooking site, but was directed here. This is my original question http://cooking.stackexchange.com/questions/35726/botulinum-toxin-in-home-canned-green-beans The reading is quite ...
3
votes
2answers
316 views

Why are there so many medicinal plants?

Here is wikipedia page containing a list of plants used in herbal medicine. One might first want to argue that many of them actually do not have any medicinal/beneficial effect on heatlth. I think we ...
5
votes
1answer
176 views

How can we tell which direction sound is coming from?

Pretty self descriptive, without being able to view the source of the noise how can we tell the difference between a sound in front of us and a sound behind us if pitch, volume and distance are all ...
3
votes
1answer
40 views

Genetic variation in humans and model organisms (measured by SNPs)

I was wondering what is the range of SNP density across species and model organisms. I.e., what would be a reasonable estimate for the SNP density (i.e., x SNPs for each 1 Kb) in: humans humans ...
-2
votes
3answers
686 views

How does the modern theory of evolution solve these apparent problems? [closed]

I hold to the truth of Evolution, but I've encountered several problems with it, that I can't answer, and I can't find an answer for, despite much research. If would be great if anyone can answer ...
3
votes
1answer
86 views

What is a good source for info on disease frequency distribution among age groups?

I need information on the disease frequency distribution among age groups for an Android app I'm building... Hopefully I've come to the right place. Is there a good data source for this? Like a ...
3
votes
1answer
224 views

molecular indicators of apoptosis: clarification needed

I understand that DNA fragmentation is a molecular indicator of apoptosis. What distinguishes this as a hallmark of programmed cell death, versus one of necrosis?
1
vote
1answer
191 views

Raphide toxicity in Pothos plant

Recently I found out that the common houseplant Pothos (Epipremnum aureum) is toxic to cats and dogs due to the presence of "insoluble raphides." I have a lot of these plants around my house and my ...
7
votes
1answer
372 views

What biological processes cause leaves to change colours in Autumn?

I am curious to learn what are the biological mechanisms that cause leaves of deciduous plants to change colour? What happens to the chlorophyll? What environmental phenomena (temperature/air ...
6
votes
2answers
519 views

Goats are so fearless but sheep are not. Is there any genetic difference responsible?

As you see in the picture goats (not only wild goats) are so fearless, but I never saw any sheep do this. What is the source of this difference in behavior?
3
votes
1answer
320 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 ...
5
votes
1answer
1k views

Why don't antibiotics affect mitochondria?

Given that mitochondria are evolutionarily closely related to bacteria, and antibiotics kill bacteria, why don't antibiotics also kill mitochondria?
1
vote
2answers
71 views

Collective term for both exons and introns

Is there a term I can use to refer collectively to both exons and introns? By collectively, I don't mean ligated as with an unprocessed transcription product. I'm just writing about exons and introns ...
1
vote
1answer
125 views

Population genetics and the fitness probability distribution. Why is the arithmetic mean all we need?

When recording change in allele frequency in diploid, bi-allelic, infinite and panmixic population we usually use this kind of equation: $\delta_p = \frac{p * q *( p (w11 - w12) + q * (w12 - ...
1
vote
2answers
66 views

The role of antibodies interacting with cancer

I'm learning about antibodies. As I understand it, antibodies detect stranger cells/bacterial/viruses by the molecules present in their membranes. In cancer cells, the cancer cell have produce some ...
2
votes
1answer
31 views

Do the phage repressors CI and Mnt exhibit crosstalk?

I am interested in using the CI and Mnt proteins as well as their respective promoters (pR and Pmnt) within the same synthetic system, but am concerned as to their similarity and potential crosstalk. ...
1
vote
1answer
132 views

Origin of human intelligence and thought

I've been debating this topic with a friend of mine and we can't get to a common answer. She argues that we don't descend from any Chimpanzee or Orangutan because, if we did, they would also have the ...
2
votes
1answer
100 views

Steroid Hormone Signalling

Can the lipid-soluble hormones (like steroid hormones) go inside every cell, as their particular receptors are located in the cytoplasm or nucleus of the target cells? Is there anything special on the ...
2
votes
3answers
389 views

Why isn't there a standard unit of promoter strength?

Sometimes in synthetic biology, we need to know rates of transcription of one promoter in relation to others (particularly inducible vs constitutive) in order to perform tasks like balancing ...
9
votes
2answers
221 views

Why is venom more common in fish and snakes than other vertebrates?

Reading this question, I wondered why is it that we associate vertebrate venoms so often with snakes and fish, and more rarely with lizards, amphibians, mammals, and birds (apparently never, in ...
2
votes
2answers
896 views

What is a cortical circuit?

I have read about cortical circuits in the context of connectomics (e.g. any example here) and computational neuroscience (e.g. any example here), but a simple Google/Wikipedia does search not show an ...
2
votes
3answers
4k views

Laying eggs vs giving birth: is there a connection with internal vs. external ears?

I have heard that "The animals who have their 'EARS' outside their body give birth to their young ones and the animals who have their 'EARS' inside their body lay eggs." Is this true? Are there ...
4
votes
4answers
1k views

Do male animals visually perceive females as more/less attractive?

If we somehow remove pheromones, do animals experience a phenomenon similar to human "visual beauty" when looking at members of the opposite sex? For example, given a set of 20 female ducks observed ...
0
votes
1answer
887 views

When can a virus modify DNA in every cell of a living organism?

I've recently heard about experiments with brain tissue, where a virus is introduced in a rats brain, causing a "glow when electric charge is present" protein to be created. This protein then helps to ...
2
votes
1answer
534 views

Water potential in plants?

The concept of water potential in plants tries (and succeeds) to explain various movement and transports in plants. I have learnt that it can be though of being composed of various components like the ...
2
votes
1answer
128 views

Can a brain be transplanted?

Is it possible to transplant a brain and would it keep the memory? If not, what would be the prerequisite to transplant one?
1
vote
2answers
85 views

Why might food spoil faster in Ireland than the US?

An American is staying in my house for the summer and claims that food (specifically, bread and milk) spoils a lot faster here than at home in California. Is there a significant difference in chemical ...
3
votes
1answer
2k views

Why do you need you room dark for melatonin release?

There is a light pollution movement that says lighting at night obstructs melatonin production. They say: What makes you fall asleep are changes in the level of the hormone melatonin ...
3
votes
1answer
120 views

In theory, would it be possible to create an injection of Vitamins, Minerals, sugars etc so that eating was no longer necessary?

I am wondering, out of pure curiosity, whether with current medical & biological science, (or indeed with accepted probable future developments in those areas), in theory, would it be possible to ...
3
votes
1answer
7k views

Why is my faeces black in color after eating Oreos

Why is my faeces black in colour the morning after I eat some Oreos? Day 1 : Eat a handful of Oreos & the next morning your stool is black. Day 3 : Eat a handful of cocoa flavored biscuits & ...
3
votes
1answer
56 views

Self pairing in DNA

I know that ssRNA molecule can fold over itself (e.g. in t-RNA). Can DNA do the same? Is there any example of this in nature? Why is this phenomenon more common in RNA than in DNA?
4
votes
1answer
125 views

How are blood vessels affected by UV and infrared radiation?

The lining of the blood vessel as an interface and boundary layer is of existential necessity to the life-support of mammals. My question is: How are major blood vessels and the blood vessel lining ...
2
votes
2answers
225 views

Why are animal births not taken as seriously as human births?

When humans give birth, more than often medical assistance is needed. Others gather around and frantically look for any way to help. But when an animal gives birth, it is usually seen as a moment ...
1
vote
1answer
61 views

What is a zygote?

During fertilization, the nuclear membrane of the pro-nucleus of the ovum and sperm degenerate. Is the cell is stage called a zygote? After the dissolution, mitosis occurs and two cells are formed.Or ...
1
vote
2answers
177 views

What use a pair of lips?

Pardon my ignorance ... A lip is apparently a very sensitive tactile device - as it at-least serves to warn it's owner they may just be about to consume something that could cause injury. Primates ...
6
votes
3answers
11k views

Why do toenails grow much slower than fingernails?

As the title suggests, I've noticed that my fingernail grow much faster than my toenails. For instance, I usually trim my fingernails every two week or so, but for toenails the number would be about 6 ...
2
votes
1answer
114 views

What in the world is this critter?

We spotted this thing crawling around a (thankfully empty) bowl in our apartment in Barcelona, Spain. I have never seen anything like it. It appears to be some kind of caterpillar-like insect, but it ...
0
votes
1answer
25 views

Stopping the effect of hormone

Many hormones released by endocrine organs travel down in the blood and bind to specific receptors on the target cells. What then breaks that binding of the molecule with the receptor ? ( thus ...
1
vote
1answer
67 views

DNA preparation for sequencing

In shotgun sequencing method or some related method that DNA is break up into random fragment. The fragment that have about 3kb in size is inserted into plasmid by enzyme ligase and then plasmid ...
1
vote
1answer
48 views

How far do 2 ant colonies of same heritage have to be in space (and generation) in order to fight?

(Kinda follow-up to this.…) I've heard before that if you put 2 ant colonies side by side they're going to attack each other. But then from the previous question, there could be "sister" ant ...
18
votes
6answers
2k views

Why isn't a virus “alive”?

The recent news about a new supermassive virus being discovered got me thinking. What biological differences between viruses and cellular organisms have made viruses be deemed non-living?
11
votes
4answers
3k views

Why do parasites sometimes kill their hosts?

It's bothered me for a while now. I understand why a parasitoid would do this, as it only temporarily requires the host, and that not all parasites kill their hosts. There seems to be no evolutionary ...
1
vote
1answer
52 views

Systematic difference of diversity between sister taxa?

When looking broadly at the tree of life, my feeling is that, after a divergence there is almost systematically one taxon that speciates way more than the other. (There will have some approximations ...
2
votes
1answer
60 views

How do cells figure out the big-picture shape?

I'm wondering what makes cells to divide (and stop) in such a way that they make our hands the shape that our hands are...

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