13
votes
1answer
15k views

Are mosquitoes repelled by high frequency sound?

I am totally confused whether ask this question to physics or biology stackexchange. I downloaded a mobile application which claims to repel mosquitoes. This application basically produces sound from ...
18
votes
1answer
530 views

Do trees age on a microscopic level?

Most animals age via at least two mechinisms: at a "macroscopic" level, basically wear and tear to the point where (on evolutionary time scales) it's more genetically advantageous to optimize for ...
4
votes
1answer
166 views

What are minerals (other than zinc) that the human body cannot store

It is known that zinc is an essential mineral that the body cannot store. What are other minerals, especially metals, that the body cannot store? (other than water-soluble vitamins such as vitamin B ...
12
votes
3answers
33k views

What is a coupled reaction and why do cells couple reactions?

I was wondering what exactly a coupled reaction is and why cells couple them. I read the wikipedia article as well as several others, such as life.illinois.edu but I still don't get it. Could ...
15
votes
3answers
488 views

Why do some trees have a life span, while some don't?

I have heard that there is no limit on the growth of trees, but then why do some trees, such as boxelders and poplars, tend to live shorter than redwoods, for example? Some advertisements for improved ...
8
votes
2answers
253 views

What are the frequency ranges of most marine mammal vocalizations?

I am trying to determine a list of frequency ranges into which marine mammal vocalizations fall. Ideally, I would like a list showing where the most popular marine mammal vocalizations fall, followed ...
12
votes
3answers
10k views

How many agarose gel bands are typical for circularised DNA

I am aware that circular DNA can be both relaxed and super coiled. However when running an agarose gel of the circular plasmid along with singly digested plasmid with BamHI and HindIII, I see 1 band ...
2
votes
0answers
97 views

Has anybody used Evrogen's DSN-normalization protocol for cDNA normalization? [closed]

I found the link to a commercial product by Evrogen to normalise cDNA samples for gene discovery projects here: http://www.evrogen.com/technologies/normalization.shtml The most up-to-date reference ...
8
votes
1answer
902 views

Under what circumstances and why is terrific broth preferred to LB broth for E.coli growth?

Terrific Broth will result in a greater density of cells compared to LB but I have certainly seen it isn't as effective for the protein production of certain proteins compared to LB or defined media. ...
6
votes
1answer
154 views

Does muscle growth trigger angiogenesis?

So heavier people generally have more blood than lighter people (this is why heavier people generally need to take higher doses of medication for the same effect of medication). They also have more ...
6
votes
1answer
736 views

Does anyone have any TOPO directional cloning tips? [closed]

I'm just about to start working on a TOPO cloning after I couldn't get it to work with standard restriction/ligation. Does anyone have any tips for TOPO cloning?
7
votes
1answer
106 views

How can I normalize mRNA samples for sequencing?

Is there an easy, inexpensive, not too labor intensive way to normalise mRNA samples so that even though one loses information of gene expression levels, each of the transcripts in the transcriptome ...
8
votes
2answers
586 views

Is it possible to live without health problems sleeping one day and not the other?

Basically, I want to know if it would be humanely possible to sleep one day, skip the next, sleep, skip, sleep, skip, etc, with a 8 hour sleep time. If you need any extra information, let me know.
7
votes
1answer
48 views

Which functional annotations could be useful?

Analyzing a genome, for a generic gene, which functional annotations (e.g from Gene Ontology) can help understanding its meaning/function or, at least, provide helpful informations? Annotations of ...
16
votes
2answers
978 views

Why is 'Grudger' an evolutionary stable strategy?

I am currently reading 'The Selfish Gene' by Richard Dawkins, which I am sure many here have read. The topic are evolutionary stable strategies (ESS) regarding cooperation. I apologise for the long ...
5
votes
2answers
173 views

Why do the brains of cocaine-users shrink faster than the brains of non-cocaine users?

http://news.sciencemag.org/sciencenow/2012/04/cocaine-may-age-the-brain.html?rss=1 Cocaine-dependent individuals showed a significantly greater-than-normal age-related decline in gray matter in ...
5
votes
1answer
197 views

How do plants intake minerals through their leaves?

How do plants intake the fertilizer when it is sprayed all over the leaf surface as a foliar feed?
14
votes
2answers
155 views

Relationship between our microbiome and personalized nutrition

Recently, it has been asked whether there are 'metabolic types' between humans that can benefit from a sort of personalized nutrition. One answer suggested that one discerning factor could be the ...
9
votes
2answers
5k views

Why is PEG important for efficient yeast transformation?

One way to do an yeast transformation is by using lithium acetate, a single-stranded carrier DNA, and PEG (1). I was wondering why is the polyethylene glycol important for the efficient ...
8
votes
2answers
138 views

Why are melodies/harmonies perceived as pleasurable by humans?

Is there any evolutionary advantage to finding melodies or harmonies pleasurable? Does the ear pick up these particular oscillating waves differently from other sounds, and if so, how does that affect ...
6
votes
3answers
205 views

Genetic effects on personality

It is said that genes are partly responsible for the choices we make in our life; our genes help to create our environment, and then that environment can influence our personality. So, beside genes, ...
6
votes
2answers
228 views

Is there such thing as a generic “metabolic type”?

A while ago I picked up a book called "Eat right for your metabolic type". The book discussed the effects of the endocrine system on the overall shape and the speed of metabolism. The book outlined ...
6
votes
1answer
696 views

What happens to a human body once a sugary snack is consumed?

I'm looking to understand the effects of sugary snacks and/or drinks on a human body. I'm particularly interested in the timing of the ingestion versus various hormonal levels that may be circadian in ...
10
votes
2answers
253 views

What can the timing of human urination tell about the human's physical condition and circadian rhythms?

I've noticed a peculiar phenomenon. A subject drinks 400 ml of water, then observes time until the urge to urinate is felt. The time is 15 minutes. The subject releases water. 14 minutes later another ...
19
votes
4answers
6k views

How many genes do we share with our mother?

Somewhere I have read we share more than 99% of our genes with every other other person and 98% of our genes with chimpanzees. What does this mean? Don't we share 50% of our genes with our mother and ...
4
votes
1answer
177 views

From inflammation to sickness and depression: when the immune system subjugates the brain

Recently, some research, for example this article has proposed that inflammation can cause innate immune cells to produce pro-inflammatory cytokines that act on the brain to cause sickness behaviour. ...
7
votes
1answer
4k views

Why is Hydrofluoric Acid so dangerous if its a weak acid?

I've read that Hydrofluoric acid (HF) is extremely dangerous to touch, but what exactly makes it so toxic? It's weak acid ($K_a = 7.2 \times 10^{–4}$) and dissociates approximately 1/1000 as much as ...
8
votes
1answer
1k views

Does the use of “var”, “x”, and/or “ssp” in a scientific name provide specific information?

What exactly does it mean when a plant has a scientific name that specifies a vairety, for example Nothofagus solandri var. cliffortioides, or when the name includes an "x", as in Populus ...
19
votes
4answers
3k views

Do trees really get a large share of their mass from the carbon in the air?

I remember hearing that trees and other plants actually obtain a large amount of their mass from the carbon floating in the air, not the ground beneath them. Does the makeup of air actually contain ...
8
votes
0answers
87 views

Using the IMGT/GENE-DB service to find RSS

I'm trying to get the data for the Human and Mouse 12 and 23 Recomination Signal Sequences (RSS), to run a classification algorithm on it. I'm not a biologist, so I apologise in advance for my ...
7
votes
2answers
219 views

During famine, does the human body do anything to prioritize which organs receive nutrients?

When food is scarce, the body slows its metabolism. Are there any other systems or processes that encourage prioritization of organs?
5
votes
2answers
3k views

Primer design for introduction of restriction sites flanking a gene of interest

I am wondering what the correct method for primer design to introduce restriction sites. Specifically between two methods. 1) Primer first partially hybridises to the gene, has a mis-match where the ...
3
votes
1answer
89 views

Majority of transcripts are from sense strand?

I am wondering whether majority of transcripts are transcribed from the 5'->3' strand? Because I encounter a lot of expressions like "anti-sense transcripts". Could anybody help clarify this? Thanks.
6
votes
1answer
2k views

Purpose of poly(A)+ RNA?

I am learning RNA-seq analysis. I always encounter this phase "poly(A)+ RNA". After searching, I got this: "Most messenger RNAs contain a poly(A) tail, while structural RNAs do not. Poly(A) selection ...
5
votes
1answer
55 views

Why are some plants frost tender?

Why do some plants have the ability to stand frost, while others can't? Does it have to do with the size of the water vacuoles in the plant cells?
2
votes
0answers
59 views

Are there examples of PTMs that add different chemical groups (and mass) to different amino acids?

I'm talking about this type of post-translational modifications. What I'm interested in is not whether some modifications can only occur on specific amino acids (that's clear), but if the nomenclature ...
3
votes
1answer
97 views

Is it harmful for someone to consume things full of bacteria if they don't get physically sick from the bacteria at all?

Or as another example - what if you touch a surface that's contaminated with potentially pathogenic bacteria (like the ones at ...
8
votes
1answer
5k views

Difference between strand-specific and not strand-specific RNA-seq data

I would like to ask the difference between strand-specific and not strand-specific dataset. As far as I know, strand-specific data means that we know which strand the transcript is from. I do not ...
1
vote
1answer
92 views

Generating custom human DNA sequences based on traits such as eye colour?

I'm wondering if it would be possible to create software (unless some already exists, but I couldn't find any) to generate human DNA (the base pairs on the double helix) containing genes representing ...
7
votes
1answer
204 views

Linkage and LD: quantitative or qualitative?

My understanding is that the concept "genetic linkage" can be expressed in quantitative form, like: A predisposing gene X was found in close genetic linkage to Y. ...
7
votes
2answers
358 views

What is the biology behind a skin “mole”?

Are the dark marks aka "moles" on our skin a patch of dead cells? If so, why is it not cleared over time? In a (probably) similar vein, why do scar marks from injuries remain long after new cells ...
2
votes
2answers
93 views

Consensus codon optimization by organism

Does a public database exist that contains this information? I'm trying to make a simple gene annotation program that will let me input a DNA sequence and then optimize it based on one of these tables ...
8
votes
1answer
896 views

Do any animals other than humans undergo menopause?

Do any animals other than humans undergo menopause? Also, is there any difference between animals in captivity and animals in the wild as regards menopause? For example, even if menopause has been ...
5
votes
1answer
825 views

What's the opposite of a thermophile?

Thermophiles, heat-loving organisms, have been a popular topic of research for decades due in large part to the utility of their enzymes in various chemical reactions (Taq Pol single-enzymedly made ...
2
votes
0answers
88 views

Mouse meta-globin mRNA problem

This is an mRNA strand of mouse meta-globin: 5'-ccccagauacggaauucgaau-3' A) Which small RNA (below) is most likely to regulate expression of meta-globin? ...
6
votes
1answer
84 views

number of RNA pol II molecules in a given human nucleus?

Does anybody have any estimate on the number of RNA pol II molecules in the nucleus of a given human cell? For example, how many RNA polymerase type II protein complexes would there be on average at a ...
7
votes
2answers
151 views

How was the guided daily amount (GDA) calculated?

We are constantly shown nutritional information on food packaging stating this food contains "x" amount of your guided daily amount. A linked to the values is here. How were these values calculated? ...
4
votes
2answers
61 views

Main methods used to predict functional annotations in GO

Can someone provide me some information about the main method used to predict the inferred electronic annotations in Gene Ontology?
7
votes
1answer
96 views

Can one dendrite pass through another?

While tracing dendrites on EyeWire I encountered the following situation. They belong to an Orientation Selective Ganglion Cell. It's the first dendrite I've noticed with such a clear 'hole' in it, ...
1
vote
2answers
209 views

Can someone identify this bird?

We recently found a nest in the back garden and a little bird inside. Can you help us identify it? The nest is quite small like the bird so we are wondering whether this is the parent or a baby chick. ...

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