3
votes
0answers
53 views

Human leukocytes (re)circulation/migration in homeostatic state

One can easily find information on the topic of leukocytes trafficking between vessels and peripheral tissues during inflammation. But what happens during normal states when there is no pathology? ...
1
vote
3answers
105 views

Can a portion of human skin cells be modified in some way to generate light? [closed]

I have come across some species of living organisms who are able to emit light at whim. Can that ability be incorporated into a portion of human skin (a specialized tissue)?
1
vote
0answers
2k views

Is a hard slap to the head a medical emergency? [closed]

I was just slapped in the head twice by my older brother (we had a fight). He hit me pretty hard with an open palm on the side of my skull, but I didn't feel dizzy or become unconscious. The stinging ...
3
votes
1answer
33 views

Authority on Microbiological Definitions

Is there an authority on definitions for molecular microbiology concepts, like an IUPAC book for chemical definitions? The particular definition I am debating is chromatin. Some say it encompasses ...
4
votes
2answers
252 views

Lyonization vs Genetic Imprinting

Lyonization is the process in which there is inactivation of an X chromosome in females. This process is implicated in mosaic forms of turner's syndrome (in this case the altered ...
1
vote
2answers
792 views

How does one calculate how to dilute a solution to working strength? [closed]

If I'm loading a 3.5ul PCR onto an agarose gel, how do I calculate how much of the 6x loading dye to add?
10
votes
5answers
1k views

Can the human brain be reduced to a binary system?

Does the brain really function like a computer as in, ultimately every response is related to a binary sequence based on whether particular neurons fire or not?
4
votes
1answer
199 views

Why is the upper respiratory tract so vulnerable to infections?

Wikipedia has the following statement on its Upper respiratory tract infection page: In United States URIs are the most common infectious illness in the general population. What is it about ...
4
votes
1answer
163 views

What happens to the umblical cord inside the mother?

After giving birth to a child, the umblical cord is cut (and stored if they want). The end connected to the child's navel will fell off eventually but what happens to the end inside the mother? Will ...
3
votes
1answer
199 views

How does Hemocytoblast constantly get formed into so many blood cells and yet remains there in the bone marrow throughout the lifetime?

I mean, Hemocytoblast is a stem cell which is constantly being differentiated into daughter cells and leads to formation of all the blood cells (having short and limited life spans), so how come those ...
9
votes
1answer
120 views

What species is this? Seashell from Indonesia

Anyone know exactly what species this is? I gather it may be an auger (family) or cerith (family) of some sort. This particular one is native to Indonesia's black beaches. Again: genus and species, ...
7
votes
2answers
195 views

Why are there no artificial wombs yet?

If the conditions within the womb are mimicked, and proper amniotic fluid with constantly recycling nutrients is maintained, is it not possible to obtain an artificial womb? Is there anything missing? ...
3
votes
2answers
82 views

Can genetically engineering the DNA of a human zygote, make it a twin of another human in entirety?

My question is simple. If I wanted to make an exact twin of an individual, will genetically engineering the DNA of the zygote to match with the individual suffice?
1
vote
0answers
28 views

How does so many replicas of different kinds of blood corpuscles form from different cells in the bone marrow? [closed]

I am interested in the process by which so many identical blood corpuscles form from an entirely different cell (within the bone marrow) altogether. How does these cells form?
3
votes
1answer
676 views

Can DNA & RNA be considered as nature's programming language?

The final frontier of Biological Sciences could be considered understanding the effects of variation in the DNA (and RNA). If after fertilization the DNA of the zygote could be genetically ...
15
votes
3answers
3k views

Superhuman eyesight

My ten year old son was reading car number plates that were too fast, too far away and at the wrong angle for any of us to read or even believe that it was possible for him to read. We thought he was ...
9
votes
2answers
150 views

Why can good music raise goosebumps?

Listening to really good music right now, I was wondering why it raises goosebumps. Is there any physiological reason for this reaction to specific wavelengths or something? EDIT: Due sometimes ...
1
vote
1answer
53 views

What is the expected number of children that need to be born for every possible point mutation to occur once? [closed]

I'm reading The Perfect Health Diet, and in it the author says that the probability of a point mutation is (175/3*10^9) per new child. He then goes on to write: In the Paleolithic, with 100000 ...
5
votes
1answer
16k views

Chromosome and chromatid numbers during cell cycle phases

A diploid cell in G1 has 6 chromosomes. How many chromosomes and how many chromatids are present in each of the following stages? Here is what I am guessing G1: 6 chromosomes ; 6 chromatids G2: 6 ...
7
votes
3answers
653 views

Do both ends of a muscle contract?

I was under the impression that both ends of a muscle contract. For instance, the fibers of the biceps run parallel to the humerus so I thought they pulled toward the middle. But now I'm confused ...
5
votes
1answer
693 views

How does a fetus retain a blood group different from its mother?

It's a well-established fact that blood group is decided by genotype. But, when a new child starts its journey in the womb, the mother's blood (along with it's agglutinins and agglutinogens) flows ...
7
votes
1answer
2k views

Why does a light object appear lighter in your peripheral vision when it's dark?

So, I am not sure I can reproduce it via images, but the steps are: 1) At night, open a window and have a look at the surface of the earth 2) Suppose there's an object that reflects a tiny amount of ...
3
votes
1answer
159 views

I found these skulls in a old bottle in the woods. Can you tell me what they are?

Can you help me identify these skulls I found in an old bottle in the woods?
8
votes
1answer
277 views

What creates the feeling of 'excess' blood pressure to an area of the body?

If I hang upside down, and feel blood rushing to my head, what structures are actually responsible for me "feeling" this excess flow of blood? Baroreceptors? Mechanoreceptors? Something else? ...
4
votes
2answers
2k views

What is biological dark matter?

I recently stumbled upon the Biological Dark Matter wiki page. Its pretty light on details, but it appears to be genetic material found in humans that doesn't fall into currently classifications. ...
2
votes
1answer
144 views

Do all sources supply all sinks on a plant?

Sources include any exporting organs, typically mature leaves, that are capable of producing photosynthete in excess of their own needs. Sinks include any nonphotosynthetic organs of the plant ...
2
votes
0answers
27 views

Why sudden stresses cause stuttering and/or other impairs in children?

The question is simple: Why sudden stresses cause stuttering and/or other temporary or permanent impairs in children (and even adults)?
6
votes
1answer
4k views

Are sensory receptors neurons?

Background There are many receptor types in the body, with various functions and various mechanisms of transduction. Receptor cells are considered to be part of the peripheral nervous system, as they ...
1
vote
1answer
115 views

Why does an complete molar pregnancy not result in a clone?

Complete molar pregnancy is one where an ovum devoid of nucleus is fertilized by a sperm after which the haploid set of chromosomes double to form a diploid set. As far as my understanding extends if ...
5
votes
1answer
131 views

what does Pro→Glu substitution mean?

Considering the paper: A single amino acid in E-cadherin responsible for host specificity towards the human pathogen Listeria monocytogenes in the abstract portion, what does Pro→Glu mean? Does it ...
2
votes
0answers
74 views

Is it possible that weak memory is due to interference between signals in the brain?

"Weak memory", as used in this question, refers to the inability to retrieve a memory that a person otherwise knows he has memorized earlier. An example of this is some fact snippet that the ...
10
votes
2answers
328 views

How can action potentials be generated through thoughts?

I think I understand how a signal is transferred from neuron to neuron (from How do the brain and nerves create electrical pulses?). My question, however, is not about the standard textbook material ...
1
vote
1answer
69 views

Is it possible for a human to get rabies from a rabies vaccine meant for dogs?

What would happen if a human was injected with a rabies vaccine meant for dogs? I know vaccines can contain weak or dead strains of the virus, but is it possible that the human could become infected ...
6
votes
1answer
81 views

Has the protein composition (with identification) in honey and other honeybee byproducts been studied?

I am interested in studying honey and other honeybee byproducts. I have not been able to find sequence or structure records for any of the contents of honey. In particular, I want to study the ...
3
votes
0answers
244 views

How close to Earth's core can organisms live?

We don't to know much about organisms living deep below the Earth's crust. Recently a team led by S. Giovanni discovered some microbes 300 m below the ocean floor. The microbes were found to be a ...
1
vote
1answer
161 views

Does DNA Ligase look for complementarity in sticky ends?

Can DNA ligase seal two non-complementary sticky ends if the reaction is incubated at the optimum conditions ? I do almost 100% double digestion in the lab. However, during ligation, when I do a ...
6
votes
1answer
544 views

Relationship between nerves and axons

I just wanted to get a realistic viewpoint of our nervous system. I understand arteries and veins, but I wanted to know how similar our nervous system is to that? I understand we have neurons (...
5
votes
1answer
2k views

How does food intake affect medicine? Why pill instructions recommends taking them before (after) meal?

Even simple vitamins seem to have this in the instruction. Why is is so? Is there some simple model of how do pills interact with food? Does it depend on the food type? (What about drinks?) Should ...
1
vote
0answers
663 views

Why do plants produce so much more sugar than they use?

I recently asked the question, "Do plants need O2 to consume energy they've stored via sugar?" to which @canadianer responded, "Yes, plants require oxygen to generate ATP from sugar. However, they ...
0
votes
1answer
40 views

Do plants need O₂ to consume energy they've stored via sugar?

This question came up as I work my way through the answers to another question I just asked. My understanding is that plant photosynthesis looks something like this (though with lots more going on ...
2
votes
2answers
105 views

Protein Structure Parameters

I'm wondering about the minimal set of parameters necessary to define a protein's structure. My understanding is that the backbone geometry is defined by the phi and psi angles (torsion angles), and ...
2
votes
1answer
39 views

Could someone entirely absorb smells by smelling?

When smelling, your nose detects the smells by absorbing them. Does this mean that, if you were in an enclosed space, you could smell so much all the smell goes, and there is none of that molecule ...
2
votes
1answer
277 views

Proteins: Post translational modification

I am a physicist and trying to understand some protein chemistry for a small project. Basically, amino acids combine to form proteins and after forming the primary structure, some chemical ...
1
vote
0answers
92 views

Does Smartphone cause ear pain? [closed]

I used samsung galaxy y for last two years. I used to speak more than 3 hours per day in the phone. Now if i bring any smart phones near to my ear, i can't bear the pain. I have little cold and 4 ...
4
votes
1answer
521 views

How much of what we eat ends up in the toilet?

An awkward question. Bear with me... In terms of mass, what percentage of the food that we eat do we end up excreting? Of course, it depends on a whole host of factors so lets assume a healthy ...
4
votes
1answer
464 views

Redheads and pain receptors

I remember reading this in a biology textbook, and decided to do a little digging. Redheads have a lower sensitivity to some pain and a higher sensitivity to other compared to people of other colored ...
2
votes
1answer
53 views

In insects, does the Alanine repeat occur on the homeodomain sequence of the abdomen or does it occur on a different sequence?

By "Alanine repeat", I am referring to the suppression of the formation of extra insect legs due to Ubx gene suppression through Distal-less repression.
4
votes
2answers
99 views

How does it make thermodynamic sense for photosynthesizers to turn CO₂ into O₂?

My understanding is that animal metabolism consists of exothermic reactions like $$\ce{C6H12O6 + 6 O2 ->6 CO2 + 6 H2O + energy}$$ This makes thermodynamic sense to me. Animals need an exothermic ...
6
votes
4answers
147 views

Enzymatic error rate

I am aware that each enzyme generate a certain amount of misproducts. This is well documented, for example, for the DNA polymerase. I am interested in enzyme involved in biochemical processes, so for ...
7
votes
2answers
183 views

Why did the Brain develop in the front in most organisms?

I was wondering: why most, well, pretty much all organism with a brain have it right in front of their bodies or at the top.

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