1
vote
1answer
102 views

Why are there no marine birds?

Walking by the lake and watching the ducks the other day a thought struck me; there are lots of aquatic birds but all remain at least somewhat terrestrial, nesting on land. Why is it that no birds ...
0
votes
2answers
89 views

Are Purkinje Action Potentials Neuronal and Cardiac?

I first thought that action potentials of His-bundle i.e. Purkinje fibers are Cardiac. However, I started to think that this is not enough. I think now that they are neuronal and cardiac. My ...
5
votes
2answers
219 views

How to identify genes required for biofilm formation

This is just a homework question: Q: Let’s assume that there is an unknown set of E. coli genes that are required for biofilm formation. Describe a genetic experiment you could perform to try to ...
3
votes
0answers
81 views

What is the biological basis of “energy” that extraverted humans draw from social engagements and introverts expend?

This question is related to this question about introverts becoming exhausted after extended social events on cognitive sciences stack exchange. As I read more on the topic of human ...
7
votes
2answers
2k views

Can human organs be transplanted indefinitely?

I watched this movie, where they rented hearts to people for a year. I wonder if it is possible to transplant a heart indefinitely from person to person, or does the heart have a lifetime? So, do ...
1
vote
2answers
41 views

C.elegans and antioxidants

How would you test the effect of antioxidants on C.elegans lifespan? Is this done through feeding E.coli with antioxidants and then C.elegans with E.coli, or is there another method?
3
votes
1answer
118 views

At which temperature is the Tick-Borne Encephalitis Virus destroyed?

At which temperature is the Tick-Borne Encephalitis Virus destroyed? If there is no data specifically for TBEV, is there any data for typical temperatures at which other Flaviviruses / Flaviviridae / ...
4
votes
2answers
2k views

Do all Gram negative bacteria cause septic shock?

Do all Gram negative bacteria cause septic shock? If they don't could they if you attacked them with an antibiotic that could lyse the cell? For example any antibiotic that attacks the cell wall, ...
1
vote
0answers
41 views

Phage base Biosensor

What kind of biosensor is made by Phages? I need a list of published paper that used Phages for make LCR(inductance (L), capacitance (C), and resistance (R) of a component) biosensor for detection. ...
3
votes
0answers
94 views

What proportion of salt in water would make it not dehydrate nor hydrate someone? [duplicate]

Drinking sea water can be deadly as it contains too much salt, basically de-hydrating the body. Normal tap water contains little salt and is good for re-hydration. My question: How much salt needs to ...
2
votes
1answer
66 views

How to determine externally that a whale is a mammal?

Mammals have external qualifying characteristics like body hair, ear pinna, etc. But a whale has none of that. So, can it be identified as a mammal just by external observations?
6
votes
3answers
331 views

Are there any known mutual symbiotic relationships that has more than two agents?

We are all familiar with the examples of symbiotic relationships in nature consisting of two agents, like lichen or the co-evolvement between certain birds and flowering plants. Do we know of any ...
3
votes
1answer
187 views

How does rate of evolution/innovation scale with population size?

I understand that there will be many other factors that affect rate of evolution/innovation. However, other things being equal, how will the rate of evolution vary between two populations of different ...
2
votes
0answers
49 views

Rosemary room temperature at winter

I consistently read in non-scientific resources that I have to put my rosemary to low temperature (about 10°C) in winter (unless I don't want it to freeze). I googled, but I fail to find a scientific ...
3
votes
1answer
345 views

Do wolves bury food like dogs?

Many breeds of domestic dogs seem to like burying food, presumably in preparation for leaner times. Assuming that dogs evolved from animals similar to the modern wolves through a mix of natural and ...
11
votes
2answers
1k views

If human eyes watch an area, what's the shape of its capturing shape? Rectangular? Half spherical?

A normal camera can capture a rectangular image. If human eyes watch an area, what's the shape of the captured region? Rectangular? Half-spherical?
1
vote
0answers
408 views

How does proximal centriole of human sperm function?

I've read that the human's unfertilized oocyte ( stuck at metaphase 2 of meiosis ) lacks centrioles and that it completes meiosis 2 after fertilization as sperm gives its proximal centriole. Then what ...
2
votes
1answer
227 views

what the best E-value cutoff in the miRNA homology search

I'm trying to use miRBase database to annotate some microRNA sequences in length 22-24bp. I highly appreciate if someone let me know whether I should do this BLAST against mature miRNA or stem-loop ...
1
vote
0answers
72 views

Loss in DNA band size extracted from polyacrylamide gel

I'm using cDNA AFLP teq.. I extracted 670 bp band from polyacrylamide (urea) gel and I have amplified with PCR but on agarose gel it stops at nearly 350 bp.it happened for most of other bands before. ...
0
votes
1answer
77 views

What is the nature of plasmids? [closed]

What are the plasmids composed of? Are they composed of genomic or non-genomic DNA? I guess the answer is "genomic DNA" but I'm not sure.
1
vote
1answer
126 views

Does pupil size affect image focus in persons with no lens?

If an individual has no lens like Claude Monet (who had them removed). They should be able to still focus the images they see in a well light area if they shrink their pupils to a very small size ...
5
votes
2answers
4k views

Are brain cells replaced over time?

You know how your cells die all the time and new ones are made to replace them, so you practically have a new body every maybe 5 years? Many people say you become a completely different person every ...
4
votes
2answers
108 views

Is there a command line molecular cloning tool?

There are many softwares such as SnapGene, Geneious, Vector NTI, ApE, Gentle and others for assistance with cloning. Their key functions are: Making maps of plasmids Annotating plasmids with common ...
8
votes
0answers
562 views

Evolutionary reasons why you cannot tickle yourself but masturbate

There are obviously good reasons that explain why you cannot tickle yourself (see e.g. here). This got me thinking why it is possible to masturbate... Wouldn't it make more sense to not being able to ...
7
votes
1answer
2k views

Why do plants fruit?

This is a two-part question: What is the point of fruit if not to be eaten? It’s is my understanding that organisms will adapt to survive and thrive. I understand that being eaten can spread seeds, ...
2
votes
0answers
61 views

How can eyeglasses improve vision beyond 100%? [closed]

The result of a vision test by my oculist yielded a result of more than 100% while wearing prescription glasses. I wonder, how can a person see better using eyeglasses?
0
votes
0answers
31 views

Why is drug clearance not affected by blood flow in case of low extraction ratios?

Background information: 1) Variation of organ blood flow: a) for drugs with low extraction ratio (<0.3): the venous drug concentration is virtually identical to the arterial concentration ...
3
votes
1answer
99 views

How does the body really react to exposure to the vacuum of space?

I've seen sci-fi movies where the effects the body being unprotected in outer space are wildly different. In one movie, a guy radios for someone who's been ejected into space to breath all the air ...
1
vote
2answers
223 views

Are fatty acids and glycerol lipids?

As far as I know, lipids are defined as biomolecules which are hydrophobic. Triglycerides are composed of fatty acids and glycerol and are considered lipids but, are fatty acids alone or glycerol ...
1
vote
1answer
36 views

Can we directly stimulate M cones in retina with current technology?

I wonder if we could try to see imaginary "supergreen" color by directly stimulating M cones. For this I suppose we'd need: Non-destructively scan specific human's retina to locate exact positions ...
0
votes
1answer
73 views

What is this bizarre in-growth in this red bell pepper?

I just chanced upon a rather strange red bell pepper (or capsicum?): The green formation is bulbous to touch, just the like the outside of the bellpepper, and it has the same smell as one. I'm no ...
4
votes
0answers
151 views

When birds fly in V-formation, how is it decided which bird gets to be the 'lead bird'?

I've read on Wikipedia and in other sources that the lead position alternates due to flight fatigue, but does it alternate between a small cabal of of leadership birds, or does (almost) every bird get ...
3
votes
2answers
1k views

How to inactivate trypsin permanently by boiling?

I have to perform a hydrolysis of BSA with the enzyme trypsin. As a control I want to inactivate the trypsin enzyme. Can I inactivate it permanently by boiling (100oC) for 10 minutes, or does it it ...
4
votes
1answer
137 views

What is 'independent assortment'?

What is the definition of 'independent assortment'. I tried researching this term but came back with two results: alleles assort themselves independently of different alleles the alignment of ...
5
votes
1answer
122 views

Congenital blindness due to retinitis pigmentosa - does it exist?

Retinitis pigmentosa (RP) patients typically become blind after a period of years in which their eye sight slowly deteriorates due to photoreceptor degeneration. Generally RP patients develop ...
4
votes
1answer
118 views

Is eating cooked food an evolved behavior or rather an intelligent one, passed down via culture?

I was just eating a rather rare steak when I started wondering whether eating foods cooked was something I would instinctively want to do if the practice hadn't been taught to me. So, is cooking food ...
4
votes
0answers
42 views

Why does a pacemaker have a negative pulse? [closed]

Why is the first phase of the pulse from a pacemaker cathodic?
6
votes
2answers
6k views

How hot can a beverage get without burning the tongue?

What is the maximum temperature that a beverage can be without burning the tongue? I suspect there's a maximum temperature that the surface tissue of a tongue can withstand without being damaged ...
3
votes
1answer
2k views

How to prepare sample for SDS PAGE?

I usually take my protein sample 0.8ml and sample buffer(2X) 0.2ml for my sample preparation in SDS PAGE. Am I using correct proportion? my protein sample concentration is 4.1mg/ml. What is the ...
2
votes
0answers
29 views

Which agricultural crops attract rodents?

Are there any data on rodent populations per acre of different types of agricultural crops?
0
votes
2answers
37 views

Resource for finding what proteins bind?

I have two lists of proteins (including phosphorylated forms). I want to determine which members of each list act on which members of the other list. What online resources exist for finding out what a ...
3
votes
1answer
242 views

Why do chameleons move back and forth?

I was always curious, why do chameleons have this strange gait?
20
votes
1answer
4k views

Why do we have five fingers?

Humans (and other humanoid mammals) have five fingers in each hand. Curious to know, why five? Wouldn't more fingers be more useful? Is there any evidence that it used to be different and natural ...
1
vote
1answer
516 views

Apoptosis vs necroptosis

I understand that apoptosis and necroptosis share the same upper part of the pathway, but I cannot seem to distinguish when is each one activated? From my readings, it seems that when procaspases 8 or ...
0
votes
1answer
62 views

Clarification on BMI formula

In the BMI formula= (Weight) X 703) / (Height^2) , what does 703 represent? What is a reliable source that I can cite for this answer? weight= lbs height= inches
1
vote
2answers
2k views

Book Recommendations: GRE Subject Test In Biochemistry, Cell And Molecular Biology

There are probably a lot of really good answers that may vary significantly in terms of content. I'm looking for a set of books that I can read in preparation for the GRE Subject Test In ...
1
vote
1answer
39 views

What is the most common way of administering loop diuretics and what is their time course of action?

I am reviewing some material on loop diuretics, and I am curious to know how these drugs are administered. Also, I am interested in knowing their time course of action once they are administered into ...
2
votes
1answer
63 views

What are the features on a microscope one needs in order to do lab work?

By lab work I mean urinalysis, blood work(live as well), fecals, cytologies, histologies and all other. I have read(partly) a book(from 2002) on lab diagnostics and the author did not mention ...
0
votes
1answer
100 views

Is “Cisternal Twins” an actual classification of twin types and if so, describe it

I always assumed my brother and I were identical twins. Now my mother, in her eighties, says we are cisternal twins, but I cannot find any references on the matter. Is there such a thing? If so, what ...
2
votes
0answers
296 views

Pink E.coli cell pellet. Reasons? [closed]

I've harvested IPTG induced E.coli BL21DE3 cells' suspension culture by spinning at 5000 rpm/15 min/4 degrees C. The pellet after spin looked pale pink colored. What could be the reasons?

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