9
votes
1answer
2k views

Why is GTP gamma S non hydrolyzable?

GTP gamma S is routinely used in studies of G proteins to stably activate the G protein. Comparing the structures of GTP gamma S and GTP, the Sulphur atom replaces the Oxygen attached to the leaving ...
1
vote
0answers
65 views

When should endocytosis inhibitors be used in cell binding assays?

I'm beginning to do some cell-binding assays and I would like for my proteins to not be endocytosed by my mammalian cells. Typical suggestions are for the cells to be kept on ice and that the binding ...
4
votes
1answer
80 views

Is there an advantage to having cellulite

There are many ads nowadays advertising cellulite removal, and it causes me to wonder if there is an advantage to having cellulite or if it is just a result of too much fat unevenly spread? Is it ...
4
votes
2answers
375 views

Does making yogurt from non-pasteurized milk work against possible disease bacteria?

In the past, when there was no pasteurization, could making yogurt from milk lower the chance of getting infected by bovine tuberculosis (or other diseases from infected milk)? For example, would ...
6
votes
2answers
970 views

Why do DNA and RNA have the functions they have?

I know that there are two most important directions of genetic information transfer in living organisms: DNA->DNA and DNA->RNA. The first is replication, and the second is transcription. I wonder if ...
8
votes
1answer
597 views

Does every mitochondrion in a cell contain the same DNA?

I know that mitochondria of eukaryotes have their own DNA, more similar to that of bacteria than to the rest of the cell's DNA. I also know that a cell can have plenty of mitochondria, and I ...
5
votes
2answers
662 views

Isotype control antibodies in Flow Cytometry

In a Flow Cytrometry, one can add an Isotype Control Antibody to allow another antibody to bind more specific to the cells. My question is, how can the Isotype Control Antibody add specificity to the ...
8
votes
1answer
876 views

Disadvantages of unihemispheric sleep

Is is well known fact that marine mammals and some birds can sleep with one brain hemisphere at a time, since it's essential for their survival. However, at least in my opinion, such mechanism would ...
6
votes
1answer
60 views

Can an organism obtaining a part of its genome via horizontal gene transfer be called a “hybrid”?

Wikipedia definition of "hybrid" offers many competing definitions. But most seem to be centered on sexual-reproduction gene transfer. Is there an official (in a textbook or widely accepted peer ...
3
votes
0answers
46 views

Physiological or molecular difference before and after sleep?

I know that the details of the process of sleep aren't entirely known, but have always wondered why I feel rested after sleep. Biologically, what differences can be directly observed in the human ...
10
votes
2answers
154 views

What is the Edward O. Wilson fuss about?

I have just read this article on E. O. Wilson and I don't understand what the difference is between what he is arguing and "standard" natural selection. I read "the extended phenotype" some years ago ...
1
vote
1answer
71 views

Expression of an ancesteral gene

Why would the expression of an ancestral gene and comparing the product to a modern protein give misleading conclusions about heredity? Update: By ancestral gene I mean a gene which was used by an ...
7
votes
3answers
225 views

What alternatives are there to the amyloid hypothesis?

Given the recent failure of the Bapi clinical trial, there is a lot of questions that have arised from he amyloid hypothesis. However, I can't really think of many other mechanisms that don't involved ...
2
votes
2answers
43 views

Recommendation of a comprehensive book on the history of medicine

I was wondering if somebody could recommend a book on the history of medicine, be it comprehensive or an introduction to the history of medicine. I know there are a lot of medical books that cover ...
5
votes
3answers
180 views

Why don't flies avoid the motorway?

Flies have a short lifespan, therefore evolution should technically happen over a shorter period of time (years). Flies die all the time from getting hit by cars on the motorway. Those flies that ...
8
votes
1answer
124 views

How realistic is to use DNA for long term storage?

This is mainly a followup question to the recent paper Next-Generation Digital Information Storage in DNA. Personally, while I agree about the data density of the format, I can't help point out the ...
-2
votes
1answer
77 views

What causes mutations in regulatory genes? [closed]

In detail, what causes mutations in regulatory genes?
2
votes
1answer
110 views

In cancer, why do cells duplicate themselves?

In regards to cancer why do cells replicate themselves? If it's a mutation, what kind of mutation would this be classified as?
8
votes
2answers
2k views

What is the concentration of ATP in an average cell?

Can someone give me some references showing the average concentration of ATP in a cell?
5
votes
5answers
269 views

What is the lowest common denominator of cancer?

What is the lowest level attribute that all cancers share? Also, what is the highest level attributes that all cancers share?
4
votes
1answer
98 views

How to quantitatively measure work done by a biological system?

Thermodynamic efficiency can be expressed as the ratio of Work done(W) to Energy invested (Q). Thermodynamic efficiency= W/Q How can one measure work done by a ...
18
votes
3answers
1k views

Is “computational biology” different from “bioinformatics”?

Are "computational biology" and "bioinformatics" simply different terms for the same thing or is there a real difference?
4
votes
1answer
364 views

Why do rod cells not recover after bleaching upon exposure to bright light?

I'm confused as to why, when exposed to bright light, rod cells cease to function. I understand that exposure to bright light bleaches all of the rhodopsin, but...so what? Why doesn't the bleached ...
11
votes
1answer
1k views

Given ATP synthase's structure, how can 3.33 protons ultimately synthesize one and only one ATP?

I am familiar with the structure and function of ATP synthase, but one small detail doesn't seem to make sense. It also happens to be a detail that seems very hard to express. Depending on the ...
3
votes
1answer
105 views

Optimization of annealing temperature

I am trying to optimize annealing temperature for some primer pairs. I have tried optimization using cDNA, genomic DNA, Taq polymerase, phusion polymerase etc., but every time I am either getting ...
2
votes
3answers
225 views

Where can I find a list of diseases and their incidence?

Say I am studying a particular disease and I know that its incidence is 0.8 per 100000 children below the age of 18, how would I find the incidence of a whole bunch of other pediatric diseases (or ...
20
votes
5answers
753 views

Why did life not evolve to use radio?

We use electromagnetic communication everywhere these days. Cell phones, wifi, old-school radio transmissions, television, deep space communication, etc. I'm curious about some of the possible ...
6
votes
1answer
68 views

(Rough) Model for DNA evolution in E. coli genes

I need a model of in-gene DNA drift. I'm not interested in bacterial phylogenies alone. Here is what I understand: Sequences corresponding to genes have both exons and introns, but in bacteria the ...
6
votes
1answer
331 views

What is Mendelian Randomization, and how is it used to infer causality in epidemiology?

Studies of human traits and diseases are inherently confined to observational studies, known as epidemiological studies. This can make it very hard to determine what actually causes a particular ...
6
votes
3answers
126 views

What gaseous substances do humans emit?

Other than CO2 and Methane what other gases do humans produce or emit? For example, does skin decomposition, or aerobic respiration emit any special gases that people don't normally realize or know ...
8
votes
1answer
321 views

Why aren't mitochondria and plastids considered symbiotes of eukaryotic cells?

Mitochondria and plastids have their own DNA, their own membranes, and their reproduction is not tied to the reproductive cycle of the host cell. However, they are considered to be organelles rather ...
8
votes
1answer
100 views

How much energy does a cell expend maintaining its contents?

In software engineering, an analogy is sometimes made using biological cells. I would like to know whether it has basis in fact. People say (Alan Kay was first) that "objects" in software should be ...
10
votes
3answers
319 views

Athletes: nature vs. nurture?

Having watched a lot of olympians the last few weeks, I was struck by how many of them have actually spent their wholes lives/careers training for their one event (be in running a marathon, or ...
4
votes
1answer
70 views

During human ageing, which immune cell sub-types are most affected?

It is now well established that human ageing is accompanied by an increase in systemic, low-grade (chronic) inflammation, sometimes termed inflammaging (Franceschi, 2007). This is in part due to more ...
8
votes
2answers
2k views

What is the life cycle of a wart?

There doesn't seem to be a lot of information available on research done on warts. What is the life cycle of a wart? How does it spread? -- specifically how does it recruit cells to spread it? What ...
4
votes
1answer
223 views

Why does muscle tissue have relatively constant AMP + ADP + AMP?

I was going over slides of energy expenditure in muscle cells. It mentions that in muscle tissue, the cell's energy charge ([ATP] / [AMP]) is the principle factor controlling glycolytic activity, and ...
2
votes
1answer
84 views

How do parasitic fungi sense optimal fruiting conditions from inside the host?

Question is pretty straight forward. Are there generally any chemical cues?
6
votes
1answer
86 views

Why are pilots under the illusion of gaining altitude without doing so?

We had a lecture about the balancing systems of the body (mainly the otolith organ / semilunar canals) in which a case was described where a pilot crashed into a ship. He was supposed to keep his ...
13
votes
2answers
761 views

Is the EC50 of an activating protein for an enzyme a good indicator for the binding affinity Kd?

We work with a membrane protein system where measuring the affinity between the enzyme and the upstream activating protein has been difficult, and when measured in detergent solution, it is almost 100 ...
4
votes
1answer
94 views

Assembly of metagenomic data

I'm trying to assemble metagenomic data that comes from termite guts. The sequences comes from SOLiD and no paired, so the reads are extremely short (25bp). I have tried multiple assemblers (CLC, ...
3
votes
0answers
60 views

What is the frequency of double-hets between parent and child?

Say both parent and child are genotyped for all SNPs. In this setup we are only looking at variant positions between one parent and child - so neither parent nor child are homozygous reference (no ...
11
votes
1answer
185 views

Salmon returning to lay eggs

To spawn, salmon return to the river in which they were born. Is it because the individuals remember the specific river, or because populations are genetically conditioned to follow specific ...
8
votes
1answer
162 views

Is there a program that simulates biology on a molecular level?

Is there a computer program that simulates biology on a molecular level? Software that has rules that simulates the rules of molecular-biology?
4
votes
1answer
152 views

Is there a way for a 19th century scientist to prove that the octopus doesn't revive?

Say a sophiscated scientist in the 19th century noted that applying soy sauce on a dead octopus leads to movement of the legs, as a result of the voltage differences resulting from the salt in the soy ...
4
votes
1answer
617 views

Is it possible for a substance to be absorbed by the hair or the scalp?

I've heard that the aplication of Monovin A in the hair would allow it to grow faster. Monovin A seems to be only A vitamin, according to the first website. Could the application of A vitamin in the ...
5
votes
1answer
80 views

Free-flowing cells and those that are stuck together?

I've been thinking about the development of an embryo from the zygote stage. How is it that when cytokinesis takes place at that stage, the cells all stick together in a little ball, but later in ...
6
votes
1answer
114 views

How are synaptic vesicles brought to the synapse?

I'm reading about how synaptobrevin is used to identify synaptic vesicles for tethering near the synaptic cleft. Since neurons have a synapse and dendrites, I'd like to know how exactly the vesicles ...
9
votes
1answer
110 views

Plumage as indicator of health in birds

Anybody know which traits of bird plumage are accurate indicators of a birds health? For example feather coloration, feather brightness, amount of feather wear, number of feathers, moult timing, moult ...
7
votes
2answers
83 views

Exactly which amino acids are phosphorylated in higher plants during state transitions?

I know it is usually stated as the threonine residue near the N-terminus of either light harvesting complex (lhc) b1 or lhcb2, but if this is somehow lost, say in a mutant, is the system flexible ...
4
votes
1answer
534 views

When is the lactase in lactose-free milk active?

Recently we have started suspecting that one of our children has hypolactasia (lactose intolerance), and so accordingly I have had my first exposure to lactose-free dairy- and dairy-like products. In ...

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