2
votes
1answer
53 views

Why can't we call dog breeds different species?

I understand this question might fall into opinion based, but I'm trying to write it so that it meets the "Many good questions generate some degree of opinion based on expert experience" part and not ...
3
votes
0answers
23 views

Why does human hair grow and behave differently depending on its location?

Why does human hair behave differently depending on its location? For instance, head hair grows to an indefinite length, but eyebrows maintain a particular length and appearance. Head hair and ...
5
votes
1answer
231 views

What is this plant …?

I would like to know what is this plant ? Does anybody have an idea ? Somebody offered it to me but there is no explanation about how to care about it... Some purple flowers appeared, during 2-3 ...
1
vote
0answers
14 views

negatively charged albumin as major carrier of acidic/negative charged drugs in blood

I reading that orsomucoid (alpha-1-acid glycoprotein) is the major carrier of positively charged (basic) drugs in the blood, while albumin carries negatively charged (acidic) and drugs with neutral ...
4
votes
1answer
68 views

Is a Ginkgo tree a conifer?

I know Ginkgo is a gymnosperm, but I was wondering whether Ginkgo is also technically a conifer. I did a Google search, and found several confident authoritative-sounding answers. Unfortunately, those ...
2
votes
1answer
39 views

Is there any knowledge of physics can be applied in to evolution?

I have asked a similar question in Biology.SE (What physics knowledge can be applied to biology of organisms and ecosystems?), but it just about organisms and ecosystems, not evolution. After watching ...
2
votes
1answer
47 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
95 views

How does most of lymph get back into the blood stream? (I don't mean the lymphatic system)

I once read that it was because of osmotic pressure that it returns to the blood stream, by entering the venules. But why? If lymph originated as plasma how come that the solute concentration is ...
2
votes
2answers
95 views

Why do we have more male infant born?

For every 104 male babies,we have 100 female babies and there is a Statistics which is more reliable (we have 997 female infant born per 1000 male infant born). what's the reason? why do we have male ...
1
vote
0answers
20 views

Is this description of etiology of celiac disease correct?

There is a detailed and, to my inexpert eyes, plausible description of the etiology of celiac disease and other autoimmune disorders posted here: http://no-gluten.org/CeliacDisease.htm Is it is at ...
2
votes
0answers
25 views

Double stranded is more 'durable' than single stranded stuff?

I'm struggling with a question I've been asked. "Why is double stranded genetic material more 'durable' than single stranded one?" I know that double stranded genetic material is more stable due to ...
2
votes
1answer
30 views

Is there any disadvantage to having a really low adipocyte count in our times?

The key feature of adipocytes seems to be energy storage. Today humans in Western countries don't have to hunger and have therefore less need to store energy in fat cells. Do adipocytes have ...
7
votes
1answer
75 views

Why is an allele dominant or recessive? [duplicate]

Alleles refer to duplicate genes, where one allele can be dominant over the other. What makes an allele dominant or recessive, given that both code for a single protein?.
5
votes
1answer
65 views

What is the name of this plant? (found in a rock)

I found it in Western Turkey.It was growing on a rock so what's it?
0
votes
0answers
15 views

Retinal eccentricity to colour sensitivity [duplicate]

Colour perception goes out to 50 degrees but is the sensitivity to RGB. Question is it the same in the four quadrants of the retinal field? That is if the red colour sensitivity eg is 30 temporal ...
3
votes
2answers
41 views

What does the gene name “lexA” stand for?

It is an important gene expressed in E. coli that represses the SOS response and also the expression of lambda lytic phase genes. UV light and damage to DNA is responsible for its breakdown and hence ...
1
vote
1answer
20 views

Could the proteome of E. coli be fluorescently labelled?

What proportion of the total number of proteins in E. coli could be fluorescently labelled for PALM/STORM imaging?
3
votes
0answers
25 views

How far can birds see? [closed]

I have heard that birds have exceptional eyesight. How far does this mean they can see? What's the resolution like? Are we talking about just vague shapes or something like, at 100 feet, seeing ...
0
votes
0answers
20 views

If what we eat can be seen in our hair, then to what degree can our food affect the “look and feel” of our hair?

It looks like most things (or everything?) that we consume, whether it is a food, drink, or something we smoke (like e.g. some drug like marijuana) ends up in some amounts in our hair. If this is the ...
5
votes
1answer
58 views

Is there any scientific evidence that a human has ever grown a third set of teeth?

This is about the possibility (or lack thereof) for a person to re-grow a new "permanent tooth" or set of teeth, to replace the teeth that grew after their milk teeth fell out. I had earlier seen ...
5
votes
2answers
124 views

Why do skin and nail go blue in cyanosis?

I have learned that Cyanosis presents with blue skin and nails. What is the reason for the blue coloration of the skin and nails? Why wont the skin and nails turn another color in the visible spectrum ...
11
votes
1answer
178 views

Why doesn't HDL cause diseases like LDL?

LDL particles pose a risk for cardiovascular disease when they invade the endothelium and become oxidized, since the oxidized forms are more easily retained by the proteoglycans. A complex set of ...
0
votes
1answer
22 views

How is oxygen and carbon dioxide exchange mediated by hemoglobin? [closed]

Oxygen is transferred by hemoglobin from the lungs to tissues, while carbon dioxide is transferred by hemoglobin from tissues to lungs. How is this regulated bidirectional transfer mediated?
2
votes
1answer
33 views

Whole genome sequence analysis software

Please help to choose Bioconductor R packages and other software for the whole genome sequence data analysis and, in particlular, the goals of false discovery mutation rate, mutations exclusion, ...
1
vote
1answer
52 views

Why is sarcoma more prevalent and common in right heart?

Ewing's sarcoma or Ewing sarcoma is a malignant small, round, blue cell tumor. It is a rare disease in which cancer cells are found in the bone or in soft tissue. It is more common in right heart than ...
3
votes
1answer
82 views

Why do men have a higher hematocrit (red blood cell count) than women?

The hematocrit, also known as packed cell volume (PCV) or erythrocyte volume fraction (EVF), is the volume percentage (%) of red blood cells in blood. It is normally 45% for men and 40% for women. ...
13
votes
1answer
1k views

Why do we experience temperatures below 37 degrees Celsius as 'hot'? [duplicate]

We always prefer to be in 20-25° C, although our core temperature is about 37°? Why is our skin temperature lower than our core temperature?
6
votes
1answer
204 views

Why do flies “rub” their front legs when resting?

I've noted that every time a house fly is resting on a surface, it appears to "rub" or "scrub" its front legs in a repetitive movement. And they do it continuously. Why?
7
votes
1answer
69 views

Can humans live without their right atrium?

The right atrium is one of four chambers (two atria and two ventricles) in the hearts of mammals (including humans) and archosaurs (which include birds and crocodilians). It receives deoxygenated ...
13
votes
3answers
1k views

Why does hair grow after trimming but remains at a constant length after a while?

Some hair especially body hair regrows after trimming but stops growing after a while. What is the mechanism behind control of hair growth and how is the length limit determined?
2
votes
1answer
35 views

Why is the Trendelenburg position used when placing and removing Central Venous Line catheters in the sub-clavian vein?

The title says it all. Why is it that patients are placed in the trendelenburg position when a catheter is inserted in the sub clavian vein? What would happen if the patient wasn't placed in the ...
2
votes
1answer
31 views

Why can blood vessel contraction be described as a second order system?

Suppose that the x-axis represents time, and the y-axis vessel diameter. Then this graph is claimed to roughly describe what happens when the blood pressure increases, then decreases. When the ...
6
votes
1answer
48 views

Chickens roosting, is it sleep or torpor?

At night when they roost, do chickens experience a state of sleep (meaning do they move from NREM1 to NREM2, NREM3 and REM) or are they in a state of torpor (reduced metabolic rate and decreased ...
4
votes
2answers
639 views

Do males of all sexual species have Y chromosomes?

I know for instance some cells are sexual, so, this got me wondering, do the males of all species that have distinct sexes have Y chromosomes?
2
votes
0answers
38 views

Why do we find some things disgusting and others delicious?

For example, why do I love paprika while my girlfriend hates it? Why do I find broccoli disgusting and she adores it? As humans, there are things we'd all agree on being awful, like rotten meat, for ...
2
votes
1answer
37 views

Using perceptual adaptation for enhancing realism of VR/other entertainment

I am quite a fan of the recent oculus rift VR glasses, but it does have several flaws over normal vision, most notably a much less wide field of view, the so-called screen door effect because of too ...
0
votes
1answer
29 views

Chemical reactions at the synapse

For my course project, I am thinking of listing out major chemical reactions that occur at synapses, along with their temporal characteristics. I could not find any textbooks to use as a starting ...
3
votes
1answer
150 views

Hydrogen Peroxide on Open Wounds

I know that H2O2 is a chemical with high oxidative potential. It can deliver nascent oxygen which can destroy bacteria. I understand that open wounds have cells that are dividing at a fast rate to ...
2
votes
1answer
23 views

Grafting vegetables onto fruit-bearing trees

There are multi-fruit trees with as many as 40 different fruit, but would it be possible to graft a vegetable onto a tree? Or maybe something in between, like grafting onto an apple tree a fruits in ...
4
votes
2answers
193 views

What do biologists mean when they use the term “biological distance”?

Here is its usage. "there is sufficient genetic control to make nonmetric traits useful in anthropological work, and such variables have successfully assigned individuals from distinct geographic ...
1
vote
2answers
58 views

Aligning multiple sequences in heterogeneous group

I have a list of ~200 DNA sequences, representing probably 50 different genomic regions but they're all mixed up. For example, if I have seq1, seq2.... seq10, ...
3
votes
1answer
48 views

Mutation Rate in Multicellular Eukaryotes

I always hear people saying that the mutation rate is around $10^{-6}$ or $10^{-7}$. I don't even know if this number is the mutation rate of genes or of a single nucleotides and I actually (almost) ...
5
votes
1answer
116 views

Hamilton's inclusive fitness approach

The underlying intuition of Hamilton's model of inclusive fitness is that we should study social behaviors from the point of view of actors -- rather than the recipients. To build his model, Hamilton ...
2
votes
2answers
59 views
+200

Why did humans become bipedal?

Somewhere in evolutionary history homo started walking upright and became bipedal. You hear these hypotheses that, by walking upright, they could see better across the grassy savannas to escape prey, ...
1
vote
1answer
29 views

What is the effect of persistent hypothermia on cardiac performance?

I define persistent hypothermia in this thread about the mechanisms of persistent hypothermia. The Graph of Katzung et al. in Pharmacology about Heart Failure: I am thinking which parts here are ...
3
votes
2answers
50 views

Is it possible to move your arms above your head when handcuffed in the back?

This move was seen in Pitch Black and i wonder if it is possible at all. Say you are handcuffed to a pole, hands in the back, and the pôle is a little higher than your head. You just want to do a ...
1
vote
1answer
40 views

Protocol for checking pipette calibrations using absorbance readings of a dye in solution?

I've been looking around the net looking for a nice protocol to validate micropipette calibrations using absorbance readings of a dye in solution. Does anyone have one they can share? I'd highly ...
2
votes
1answer
29 views

What is the importance of urea in mass spectrometry?

What is the importance of urea in mass spectrometry? We use 8M urea to FASP our proteins prior to mass spectrometry. What is the significance of using 8M urea? and how does it affect the proteins?
5
votes
1answer
161 views

What physics knowledge can be applied to biology of organisms and ecosystems?

In the wiki page of Biophysics: Biophysics spans all scales of biological organization, from the molecular scale to whole organisms and ecosystems. But after searching on the internet; the ...
2
votes
2answers
53 views

How do humans perceive time?

We can see length, and other physical quantities. We can perceive through our other senses like (temperature through thermoreceptors, weight through pressure receptors etc.). But how do we "sense" ...

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