5
votes
3answers
2k views

How does Artificial Selection work?

As far as I know for evolution to work mutations are necessary. Mutations are the raw material on which natural selection works. But mutations are always completely random and human beings have no ...
3
votes
1answer
306 views

What are samples of “Outlaw Genes”

I read this in a paper Keller and Ross describe their greenbeard gene as an ‘outlaw’. Admittedly, the comment is only made in passing, but are they correct? In this context an outlaw is ...
7
votes
1answer
335 views

How fast do different organs turn over cells?

It is said that the human body turns over all cells or molecules in 7 year cycles. This is not quite correct, because there are different organs changing at different speeds. My interest is what is ...
3
votes
2answers
296 views

Two subunits connected by only one disulfide bridge: quaternary structure?

I've always simply assumed quaternary structure to be characterized by non-covalent interactions such as hydrogen bonding, van der Waals interactions and whatnot. However, if two distinct polypeptides ...
7
votes
2answers
105 views

Does the word “polymorphism” refer to the gene, the phenotype, or both?

In genetics, does the word "polymorphism" properly refer to genes, to phenotypes, or both? For example, if there are two alleles that lead to differences in the structure of the D2 neuroreceptor, ...
4
votes
1answer
145 views

Regarding TIMP and MMP enzymes

Are there substances that can promote TIMP enzyme production, or MMP enzyme production or supression in tendons? Are there medical tests that measure quantities of MMP and TIMP enzymes in tendons?
0
votes
2answers
646 views

What part of food gives the blood red color?

Roughly, what I know is, when we eat food it goes into our: Stomach > Small Intestine > Large Intestine > Rectum. So, it just moves through a digestive pipe. What I don't understand is, what part of ...
8
votes
1answer
406 views

Why are we using upper teeth and lower lip on labiodental sounds?

I came to wonder this when studying language (as well as other same theme question posted just few ago). For example the word "fantastic" we use upper teeth and lower lip to produce F sound, instead ...
5
votes
1answer
697 views

How and why did mouth and nasal cavity evolve separate?

My initial objection is that nose filters air, mouth is for eating but is used for breathing also, plus they both are used to create sounds. What is the cause and reason in this case, why do we need ...
2
votes
0answers
152 views

Too few transcripts from transcriptome assembler Oases

I am trying to run Oases for transcriptome assembly. The result is far from expected, so I would like to ask whether I am running it in a right way? Thanks. Here is my running command: ...
3
votes
1answer
5k views

What is the functional difference between hemoglobin and ferritin?

I read that both hemoglobin and ferritin are for storing iron in the body. So, what is the difference between them in terms of storing/binding iron?
3
votes
1answer
13k views

Why are (some) cats attracted by bleach?

(Sorry if this question is only partly biological) I have noticed that several cats (including the one that keeps sleeping in my house), are fond of the odor of bleach (eau de Javel) and chlorine. ...
8
votes
1answer
135 views

Is there a comprehensive database of fossils (with images) online?

Not sure if this is the best stackexchange to ask... I have not been able to find a decent database of fossils on the web, does one exist? Here are some of the links I have found through Wikipedia ...
3
votes
1answer
95 views

Color of the Fur coat of Polar bears

Recently I was playing a quiz and a question was asked about the color of the fur coat of a polar bear. To my surprise the answer was black. I thought it was yellowish white or creamy. Why so ?
28
votes
2answers
574 views

Why don't teeth glow?

Hydroxyapatite is the main component of tooth enamel. It contains phosphorus in the form of phosphates, pyrophosphates etc. that are found to exhibit the the property of phosphorescence. But why don't ...
6
votes
1answer
86 views

Can NSAIDs impact negatively the healing of tendons?

There are a number of articles regarding NSAIDs having a negative effect on healing conditions like tendonosis and tendinitis. From what I understand the channel through which they reduce inflammation ...
8
votes
1answer
99 views

What would be the best dredging/trawling tools to collect macrofaunal priapulids?

Title says it all. I've been searching for the best way of collecting macrofaunal priapulids and would like advice on sampling methods and particularly sampling tools. Since large priapulids are ...
7
votes
1answer
536 views

ChIP-seq vs ChIP-exo

I'm currently investigating ChIP-seq vs. ChIP-exo for finding binding sites. As far as I can tell, ChIP-exo seems to be better in every way than ChIP-seq... but then again, I'm not strong in this ...
3
votes
2answers
123 views

How distantly related are eusocial insects? Aren't members of a species much more related than 1/4, 1/2, or 3/4? [duplicate]

Possible Duplicate: How many genes do we share with our mother? I went to a lecture that talked about the behavior of social insects in terms of their relatedness of genes. For instance, ...
12
votes
4answers
214 views

Are there any examples of proteins with no or minimal sequence identity, but highly similar structure?

What are they, and do they share a common ancestor? How far back in evolutionary time must we go to find them? If none are known, what computational tools might be used to search for such examples?
4
votes
1answer
77 views

How quickly do estrogens break down in the environment?

Of all the synthetic hormones we use, estrogens are probably the most common. They are used for birth control as well as hormone replacement therapy. This researcher also shows that there is plenty ...
6
votes
2answers
165 views

Effect of single-gene overexpression in the cell's response

Which are the factors that modify the overall gene differential expression by introducing a vector for single-gene overexpression? If you overexpress a gene for a protein involved in signal ...
5
votes
1answer
652 views

Is there a relationship between efficiency of cellular metabolism and warm-blooded-ness?

My BIO 101 book states that when human cells convert glucose to ATP, the process is only approx 35% efficient, and much of the potential energy is lost as heat. However, that heat is useful to us in ...
6
votes
1answer
176 views

Understanding Membrane / Resting Potential from the perspective of ions?

From wikipedia article RESTING potential: "there is no actual measurable charge excess in either side. That occurs because the effect of charge on electrochemical potential is hugely greater than ...
12
votes
2answers
1k views

Why do we like salt?

A few friends of mine told me that salt provides zero nutritional value to us, and in fact can harm our bodies. Now, these guys are medical students, and being an engineering student myself, I decided ...
5
votes
1answer
139 views

Which cells are responsible for the extracellular matrix remodeling?

I am studying a case of tendinopathies induced by an alteration of how the extracellular matrix is being remodeled. From my understanding there has to be a careful balance of MMP (metallproteinases) ...
3
votes
1answer
346 views

Does caffeine increase the speed at which sperm travels?

I'm not even sure if this claim is true, but... This source states that Caffeine gives both types of sperm a boost, but the Y-sperm would get a little more of a boost. This article reinforces ...
6
votes
1answer
396 views

Are the cytosol and extracellular fluids electrically neutral?

I've found several sources that state that overall, the cytosol of a cell is electrically neutral. The extracellular fluid is also purportedly electrically neutral. How can that be when we have ...
6
votes
2answers
847 views

What is the correct model for enzyme-substrate complementarity?

This Wikibook shows both proposed models of enzyme-substrate complementarity, the Lock and Key model and the Induced Fit model. I've always been taught that the Induced Fit model is the proper one. ...
17
votes
1answer
956 views

Is kissing a natural human activity?

The word natural here is meant in contrast to it being a sociological construct. Is kissing in all its forms something natural for humans? Is it instinctively erotic? Or is it just a conventional ...
3
votes
1answer
323 views

Troubleshooting bioconjugates migration in a SDS-PAGE gel?

We do a lot of bioconjugation chemistry (click chemistry in particular but also NHS and Maleimide chemistries). Our method to valid the conjugation reactions have been to use SDS-PAGE gels followed ...
8
votes
1answer
274 views

Are there dog breeds that are so far apart genetically that they can't produce viable offspring?

Obviously, a very large dog would have difficulties mating with a very small dog and vice versa. But putting that problem aside (using, say, insemination), considering the large variation of dog ...
3
votes
1answer
201 views

T7 phage promoter action in mammals

Does anyone know if the T7 phage promoter is efficient in mammalian systems?
4
votes
2answers
1k views

Online course on Plant Taxonomy and Physiology

After following a course in Permaculture, I realised that if I want to get serious about it, I need to be able to distinguish plants. So I am looking for an online Video course on Plant Taxonomy and ...
3
votes
0answers
48 views

Is there a gene that starts meiosis 2? [closed]

Yesterday I thought about a question and asked it to my friend. The question was which gene is completely the same for a male cell that made meiosis 1 recently. My answer was the gene that starts ...
5
votes
2answers
240 views

Energy use by muscles, actual work done by muscles and more

Lately, I've started exercising in the gym and outside. I've also started to look at the details of food I eat. Food usually has a label saying the amount of energy is inside it. For example, some ...
1
vote
1answer
187 views

Which concentration of BSA is recommended for dynamic light scattering experiments?

What is the recommended concentration of BSA to be mixed with water so as to prepare a very dilute solution in order to clearly study the intensity-intensity correlation with single scattering ? I ...
5
votes
1answer
155 views

Is there such thing as Animal non-verbal body language?

Have there been any studies done on the animal use of their bodies to signal, communicate or express their emotions, particularly to members of other species (ex: humans)? I've been observing a very ...
9
votes
2answers
156 views

Modularity of transcription factors

I attended a seminar about neurogenesis that presented results for PAX6 as an important TF that contains 3 domains with very distinct patterns of downstream expression. The speaker ended up saying ...
6
votes
1answer
343 views

How can I predict DNA binding affinities from a protein sequence?

Are there any computational tools to predict the binding affinity to specific DNA motifs from protein domain sequence information?
2
votes
1answer
223 views

Are Bovine serum albumin, Avidin, Ficoll-70 and Dextran-70 positively charged or negatively charged? [closed]

Bovine serum albumin, Avidin, Ficoll-70 and Dextran-70,are they positively charged or negatively charged ? And which other solvents can be used as a substitute to water for preparing solutions in each ...
8
votes
1answer
556 views

What causes knuckle “popping” and the feeling of relief that comes from it?

Many people like cracking their knuckles. I have always been curious about it. What happens when we crack knuckles? What creates the POP sound? Why do we get a relief-like feeling after doing it?
4
votes
1answer
132 views

What biological systems are affected by Vitamin B6 (or B vitamins in general)?

B vitamins and particularly the B6 vitamin appears to the one of the main ingredients in energy drinks. There has been anecdotal evidence from people interested in dreaming that ingestion of vitamin ...
4
votes
2answers
171 views

Is there a good field methods book that covers terrestrial ecology?

In the past I have used Limnological Analysis by Wetzel and Likens and Methods in Stream Ecology edited by Hauer and Lamberti to develop labs and research methods for courses and projects with an ...
4
votes
0answers
211 views

How do I save a coffee damaged wasp? [closed]

I found a wasp in one of my coffee cups about 1 hour ago. There was barely any coffee left but it had managed to get itself pretty much drenched in coffee. I took it out. Put it on a piece of paper ...
8
votes
2answers
86 views

Is there a Reverse Transcription optimization for long, 9kb, transcripts?

Has anyone optimized RT for long transcripts (9kb)? The downstream application will be PCR amplification and Illumina library prep. It will be trivial to make internal primers sets for the PCR that ...
0
votes
1answer
103 views

What impacts on metabolism are likely from the 6x increase in water consumption by Americans at restaurants since the 1950s?

CDC data show that American water consumption in restaurant meals is 600% of what it was in the 1950s while meal calorie density has decreased (kcal/oz). What impacts is this likely to have on the ...
6
votes
2answers
109 views

phylogenetic analysis of gene enrichment?

Are there any tools to do phylogenetic analysis of gene enrichment? This is, I have a list of genes from an experiment performed in several species, with a z-score that can be described as ...
5
votes
1answer
189 views

Formal definition of a 'genetic trait reservoir'?

I've read the tomato genome paper in Nature published recently, and they describe the tomato genetic resource as a rich trait reservoir that will provide biological ...
3
votes
1answer
250 views

Why apes started to contemplate and become altruistic? [closed]

I was asking this first on philosophy forums, but it is suggested, that answer could be found from evolutionary view of point, so here we go: Again my question raised when thinking of myths, their ...

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