5
votes
2answers
147 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 ...
5
votes
1answer
814 views

The genetic and physiological origins of laughter?

This Wikipedia article defines laughter in many terms, such as... "a visual expression of happiness, or an inward feeling of joy" and "a part of human behavior regulated by the brain, ...
4
votes
1answer
51 views

Microbial Fuel Cell Reaction

I found a formula online which explained the reaction which occurred in the anode chamber of a microbial fuel cell but there was a typo $\small NADH + Ferredoxin_{(ox)} (NADH-Ferredoxin\ ...
4
votes
2answers
412 views

In biosynthesis of cysteine and methionine, where does the sulfur come from?

Methionine and Cysteine are the two amino acids containing sulfur. According to wikipedia, cysteine is built from methionine. However, the wikipedia also claims that methionine is synthesized from ...
4
votes
3answers
2k views

What is the equivalent of shutter-speed in Human eye?

I just learned that in video cameras, every frame of the video has its own shutter speed. And I know how frame-rate in human eye works out, well, not completely, hence the question. ...
4
votes
3answers
5k views

Why are 3 nucleotides used as codons for amino-acid mapping in DNA?

DNA is made of 4 unique nucleotides. When coding for a protein, a sequence of 3 nucleotides is used to code for each amino acid. Why are codons 3 nucleotides in length? A related question can be ...
4
votes
2answers
2k views

How would a plant sprout and grow in a zero gravity environment?

Have any experiments been carried out involving sprouting and growing plants in a zero gravity environment? If so, what was the outcome? How did the plants sprout out of the soil without gravity? Did ...
4
votes
1answer
2k views

What are differences between formation of embryonic disc in chick and mammal embryo?

Exam question which got lowest average points in my university: 1/5 average. No markscheme available so my attempt below. I assume that embryonic disk prefers to germ disk such that Formation prefers ...
3
votes
1answer
50 views

What is the film that covers the tongue?

What is the film that covers the tongue in the mornings, even after brushing the teeth and tongue the night before and why does it have color variations? Do the different colors mean anything?
3
votes
2answers
82 views

Humidity for wood rotting

If I put a piece of wood in a humid environment (basically humid air), it will start to rot. Does the humidity influence the rotting speed, and if so, what is the relation between the rotting speed ...
3
votes
1answer
1k 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
3answers
424 views

Identification of an Insect (Hemiptera)

I found a a few of these guys on my composter, so they could have easily been eating bugs or decaying organics (or both): To me it looks like a stink bug with oversized legs, not like the ones I'm ...
2
votes
0answers
55 views

Why Mammals are unable to produce Essential Fatty Acids?

While we have to get them from our diet and if they aren't taken in our diet we will face disease.Then why we don't have the enzymes which are require for EFA synthesis???
2
votes
1answer
55 views

If two definitive ovums are fused will they form an organism?

Pretend that somehow in a laboratory two definitive ovums (finished 2nd miotic divisions) are are fused together. Will they form a new species?
2
votes
1answer
126 views

Why are hybrids infertile?

Let's take a quote from Wikipedia about zebroids. Donkeys are closely related to zebras and both animals belong to the horse family. These zebra donkey hybrids are very rare. In South Africa, they ...
2
votes
1answer
143 views

List of heritability estimates in humans?

Many people on this site ask questions that directly or indirectly have to do with heritability in human. Do you know a list of estimates of heritability of various traits in humans? Or could you try ...
2
votes
2answers
86 views

Real time PCR normalization algorithm

When performing normalization of real time PCR results, I found two ways of doing it: In my lab they follow the next layout: $efficiency^{-(CT\ interest\ gene - CT\ housekeeping)}$ each time ...
2
votes
2answers
108 views

Sources for common laboratory Saccharomyces strains?

I'm used to working with bacteria - some of the more common laboratory strains sometimes come with an order from some vendors. What's the most convenient source to order common straings of ...
2
votes
1answer
472 views

Is there any advantage of having a mitochondria for aerobic respiration?

If we consider the pathway of breakdown of glucose which includes glycolysis, the citric acid cycle and the electron transport chain, all these processes takes place in some prokaryotes and ...
2
votes
2answers
108 views

Do people with colorblindness have less cones or no cones of a certain type?

https://en.wikipedia.org/wiki/Color_blindness#Red.E2.80.93green_color_blindness Protanopia (1% of males): Lacking the long-wavelength sensitive retinal cones, Deuteranopia (1% of males): ...
2
votes
1answer
69 views

Formation of ammonia from air and moisture

On extended bicycle trips I sometimes slept under a plastic sheet, which helped with mosquitoes on hot nights. But there was a noticeable build-up of ammonia which made this almost impossible for more ...
1
vote
1answer
47 views

How is the rate of transcription influenced by temperature?

How is the rate of transcription influenced by temperature? More precisely, I am looking for an article who quantitatively measured the rate of transcription of an "average gene" and show how this ...
1
vote
1answer
48 views

Is there a possibility that medicine will affect the efficiency of natural selection?

I mean, saving sick people means that they possibly can propagate something that nature does not allow. I know that there is already something that operate at genetical level producing alteration, ...
1
vote
2answers
216 views

What actually are the blood groups for human being?

We all know that, Human blood groups are of 4 types with Negative and Positive of each types. The Wikipedia article also states so. But according to this forum thread there are some other types too: ...
1
vote
1answer
787 views

Why do different humans look different?

Although farmers appear to be able to tell their cows apart, cows look very much alike to me. And this similarity in appearance seems to be a general trail across the animal kingdom: one individual of ...
1
vote
1answer
96 views

building intelligent structure with random evolution requires series of non useful steps

In order to build an intelligent design such as a bridge or a mechanical watch, you need a series of non useful steps. As far as I understand, in random evolution theory, the "intelligence" involved ...
1
vote
1answer
89 views

Pedigree Diagram help

I am asked to fill the genotypes in the spaces provided but looks like I am aving a little bit of trouble. can anyone help? thanks in advance!
1
vote
1answer
57 views

Artificial Propagation and it's relation to asexual reproduction

I know that asexual reproduction is also called vegetative reproduction. However I do not understand it's relation to artificial propagation. Is it a technique used for asexual reproduction (the ...
1
vote
1answer
7k views

White eggs can be considered as non-vegetarian?

I am basically a vegetarian and I find it very difficult to get an actual biological answer for this question on search engine. There are couple of links which discuss these argument but can not be ...
0
votes
1answer
50 views

How non-invasive blood glucose concentration measurement work?

Diabetes patients need to conduct the “fingerstick” a few times a day. One of the mechanisms of "fingerstick" is to take small amount of blood sample and put it onto a test strip. The enzyme on the ...
0
votes
1answer
77 views

Is it possible to convert nerve signals or electrical activity into a readable format? [closed]

Can we have the technology to recreate the informations (like images, sounds etc.)[as in the form of signals in our mind] from human mind to human understandable format? In short, can we read human ...
0
votes
1answer
122 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
2k 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
59 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
494 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
275 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 ...
115
votes
4answers
15k views

Why do I only breathe out of one nostril?

I was just sitting with my hand next to my nose and I realized that air was only coming out of the right nostril. Why is that? I would think I would use both, it seems much more efficient. Have I ...
72
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 ...
47
votes
11answers
10k views

Can humans survive without consuming life? [closed]

Some people say that it's awful that humans eat animals. They feel that it's barbaric, because you're killing life and then on top of that, you're eating it, and that you should eat vegetation ...
38
votes
2answers
7k views

Do ants or other insects sleep, and if so why?

I was thinking yesterday about insects (as there was a spider in the house, and I couldn't help but think of anything else, even though they aren't insects), and I started to wonder if ants sleep? ...
36
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 ...
33
votes
1answer
16k 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 ...
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.
16
votes
2answers
6k 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.
27
votes
1answer
4k views

What causes morning wood?

Sometimes men wake up with an erection in the morning. Why does this happen?
15
votes
8answers
8k 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 ...
13
votes
1answer
554 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 ...
12
votes
1answer
770 views

Supercomputer Vs Human Brain

With supercomputers doing calculation in petaflops ($10^{15}$ Calculations per Second), have we crossed the speed of Human Brain?
32
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 ...
23
votes
4answers
4k views

Why don't mammals have more than 4 limbs?

Arthropods have 6 or more limbs and arthropods with 6 limbs appear to move faster than arthropods with 8 limbs so I wonder whether this might have something to do with fast and efficient locomotion. ...

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