1
vote
1answer
112 views

How do tight junctions in stratified squamous epithelia affect nutrient supply?

In histology we know that epithelium tissue isn't vascularized so it takes the nutrition from Lamina propia (CT) via diffusion and in other hand we know all epithilial cells have tight junction which ...
2
votes
2answers
160 views

Where to find the corrected BLOSUM matrices?

I was looking at this paper which talks about the miscalculations in the BLOSUM matrices and how the "wrong" BLOSUM62 matrix performs better than the corrected version. I was trying to find the ...
4
votes
3answers
60 views

How many Type II restrictions enzymes are currently available (commercially) [closed]

How many Type II restrictions enzymes are currently available (commercially) for purchase as of the date of this posting (September 1, 2014)
1
vote
1answer
59 views

Applying Constraint Programming to sequence alignment/analysis

My Masters program is focused on formal methods such as SAT solving and constraint programming. I am interested in applying such techniques to problems in sequence alignment and sequence analysis, ...
3
votes
0answers
60 views

Synthesis of Fatty Acids Longer than 16 Carbons

I understand that the human body when performing Fatty Acid Synthesis can synthesize only until C16 (palmitate). However the ER has desaturases and elongases. I know that desaturases are used to add ...
1
vote
1answer
126 views

Are retroviruses cytotoxic?

There are typically hundreds of retroviruses found in healthy human beings. Are retroviruses then cytotoxic? (In other words, are they able to kill or damage other cells).
2
votes
1answer
274 views

It is possible for person with AIDS be negative for HIV antibodies?

I'm just curious as there was a bit controversy around this topic. It is possible for person with AIDS be negative for HIV antibodies? As of 1989, the CDC reported that 5% of all U.S. AIDS patients ...
4
votes
4answers
163 views

Collective name for the X- and Z-chromosomes

Chromosomes are grouped as sex chromosomes or autosomes, with the X, Y, Z and W all falling in to the former category. The Z and X are present both in the homogametic and heterogametic sexes, and the ...
3
votes
1answer
86 views

Propensity Score for amino acid

What is the meaning of propensity score of amino acid? How is it calculated? (I have not studied biology since last 8 years and now I am going through it because I need it for my research. So if ...
0
votes
1answer
4k views

What is the importance of hydrogen bonds in water? and other questions: [closed]

These are extremely simple questions — basic biology — but I would like to make sure that the way I have answered is at the very least correct. Hydrogen bonds are very weak, so how is it possible ...
3
votes
2answers
890 views

Why has our nose evolved with the nostrils facing down?

For most animals, the whole bottom of their face sticks out and they have a snout with a mouth and nose at the end. But humans have a flat face and just a nose that sticks out. We used to have the ...
14
votes
8answers
2k views

Is there a biological mechanism for evolution encoded into our DNA?

Throughout high school, I remember learning about Darwin's theory of evolution as if it were near-fact. But something always seemed wrong about the ideas presented. Survival of the fittest Random ...
2
votes
1answer
122 views

Species identification, tree from Ecuador

This tree is recently photographed in Quito, Ecuador. It grows everywhere. I'm new to South American flora, so I'd like to know what the species it is?
3
votes
2answers
722 views

Can ants sense food from a long distance?

I recently had ants find and then swarm to a food container that I put down on a desk, and I'm curious as to whether an ant would have needed to get lucky, discovering the food after crawling up the ...
0
votes
1answer
77 views

Is there any evidence that soft tissue can be preserved for 65m+ years and if not what hypotheses exist to explain it?

I read an article on howstuffworks.com and they mentioned how we have found soft tissue in dinosaurs. According to the article even Mummies and Mammoths have no soft tissue left. Is there any evidence ...
1
vote
2answers
65 views

Pharmacology: Drug Administration

Why is the enteral route seem by far the most common way to administer a drug to the body?
4
votes
1answer
472 views

Is it essential to add cholesterol to agar or liquid culture for C. elegans?

In preparing agar plates with NGM, and also liquid cultures for growing c elegans, how essential is the addition of cholesterol and heavy metals? I have prepared both. I can't notice any obvious ...
1
vote
2answers
95 views

Why are human children more likely to get lice (nits) than adults?

By my own experience, lice seems to be prevalent in the hair of human children, but not in adults. My question is Why are human children more likely to get lice than adults? Assumptions: Can be ...
0
votes
2answers
1k views

Does scratched Teflon coated frying pans contain carcinogens which can cause cancer? [closed]

Is it true that using scratched Teflon-coated pans contain carcinogens, and if so, can they be consumed through the food cooked in them? E.g. The deadly toxins from non-stick frying pans
3
votes
3answers
124 views

Is there a specific word for bacterial death?

What do you call it when a bacterium dies? Cellular death is apoptosis, necrosis, and bacterial is ...? I don't simply want to write in a paper that it - well dies!
5
votes
2answers
143 views

Premise of life cycle synchronization between predator and prey

While reading about the predator satiation hypothesis of the periodical cicadas' 13/17 year life cycles, I started wondering about its premise. By the way, I understand the math behind the prime ...
1
vote
0answers
41 views

Evolution of sexually concordant genetic variation on the X-chromosome

It was theorised in 1984 that sexually antagonistic genetic (SA) variation should more easily evolve on the X-chromosome. This is partly because female beneficial/male deleterious mutations face less ...
3
votes
1answer
79 views

Does isolation have any effect upon mouse behavior?

I work with a lot of mice. I don't do any behavioral analysis, I just inject DNA or RNA and do imaging assays. However, I have noticed some effect of isolation on mouse behavior. Normally, the mice ...
1
vote
1answer
1k views

Pharmacokinetics: why do certain drugs follow zero-order kinetics?

I understand that alcohol and phenytoin are two examples of drugs that follow zero-order kinetics. Why do these two particular drugs follow zero-order kinetics as opposed to first-order kinetics?
2
votes
0answers
38 views

Genome-wide methylation analysis: sources of technical error?

We are doing a genome-wide analysis of methylation via bisulfite sequencing for an insect species. Previous experimental techniques have suggested the presence of methylation in this organism, ...
5
votes
1answer
605 views

Microsatellite shifts (peak calling) GeneMapper! Thesis help!

I'm a masters student attempting to conduct a parentage analysis on a population of fish for my thesis. My advisor and post-docs haven't been very helpful, so I need some help! I have dinucleotide ...
1
vote
0answers
33 views

How are isopotential maps computed from EEG channel data

I have some EEG recordings of $1$ minutes, with $500$ samples per seconds and $63$ channels. For each recordings, this effectively yields a $30,000\times 63$ matrix $M$. How do I extract isopotential ...
3
votes
1answer
329 views

What is the best current understanding of how yeast transformation works?

I would like to get myself up to speed with what is currently known to science about yeast transformation. Specifically, transformation of plasmids and linear DNA fragments. I am particularly ...
8
votes
2answers
82 views

What is this beetle? Found in heather in snowdonia

We were walking in the hills of snowdonia the other day and my girlfriend found this in the heather: I've never seen anything like it. Can anyone identify it? It was the biggest beetle I've ever ...
6
votes
1answer
80 views

Can microdialysis be made in Drosophila melanogaster?

I've asked this before in stack overflow's cognitive science community, and someone recommended me to ask here: I've found a couple of studies using microdialysis on insects, but didn't found any in ...
3
votes
2answers
946 views

Does osmosis take place in prokaryotic cells?

As far as I know, osmosis occurs in Eukaryotic cells, and I'm wondering if it could take place in prokaryotic cells too.
2
votes
2answers
226 views

What is a membrane potential?

I know this may be silly, but I am confused to what a membrane potential actually is. I understand that at resting membrane potential is -70- -80 mV. But what does that exactly mean and how does this ...
6
votes
1answer
139 views

What is this creature?

Since it has six legs, I believe it's some sort of insect, but I could be wrong. I spotted it in my Central Texas backyard (Austin area). It was very slow and not at all skittish. For size ...
0
votes
2answers
467 views

Can viruses that normally infect eukaryotic cells also infect bacteria?

Can standard viruses infect bacteria? I'm not speaking of bacteriophage but typical RNA and DNA virus such as influenza and Ebola.
2
votes
1answer
93 views

can a bacterial protease inhibitor cocktail be used for Western Blotting involving HUVEC cells and HT-29 adenocarcinoma cells?

Dear fellow biochemists, I need some advice on Western Blotting, more specifically the use of certain protease inhibitors with the RIPA cell lysis buffer and protease inhibitor cocktail. A Millipore ...
1
vote
1answer
292 views

Does E. coli survive at any pH level?

Does E. coli survive at any pH level? If I was to incubate it in agar of different pH, would it still form a bacterial lawn as it's called?
3
votes
2answers
349 views

19th century Latin species description

While reading a 19th century text of new species description, I'm confused by some Latin phrases. The case here is: Corp. long. 8 poll., caud. 9 poll. I guess 'corp.' and 'long.' are ...
1
vote
1answer
65 views

Modelling how much cadmium a cell will be able to chelate with phytochelatins

I am involved in a synthetic biology project where I have to do modelling with ODEs. The biological process I want to model is the chelation of Cd2+ with phytochelatins, to know how much can be ...
0
votes
0answers
33 views

Is it possible to convert nerve signals or electrical pulses into a readable format? [duplicate]

Can we have the technology to recreate the informations (like images, sounds etc.)[as in the form of signals in our mind] from human mind to human understandable format? In short, can we read human ...
2
votes
1answer
78 views

NMR spectroscopy detection methods for proteins

While studying, I've stumbled upon a table comparing the sensitivities of different detection methods in NMR spectroscopy: "Direct", "DEPT" and "Inverse", where "Inverse" seems to be the most ...
1
vote
1answer
35 views

How to identify the genes that distal enhancers pair?

I am writing a project proposal and I have to talk about this problem: how to identify the genes that distal enhancers pair? I am really new to this topic and I don't know what it is all about. I ...
3
votes
1answer
86 views

How do nicks in the DNA strand affect the success of Long Range PCR?

Long Range PCR using NEB Master Mix - Hot Start Taq was working fine for me (amplicon sizes of ~10kb) but stopped working all of a sudden. Is it possible that many freeze-thaw cycles on the DNA ...
2
votes
0answers
43 views

What should be the distance between plant promoter and gene?

I am trying to clone a rice gene under a different endogenous rice promoter.I will be cloning the CDS of the rice gene.So I wanted to know what is the minimum or maximum distance I should put between ...
2
votes
1answer
477 views

Enzyme Assay, absorbance change to concentration change

I have a few issues with this question. An enzyme assay is performed and the kinetic data graphed. The y-intercept of a Lineweaver-Burk plot is 0.6 min/ΔA. The substrate being assayed has a molar ...
4
votes
2answers
768 views

What happens if a person has the right side of the body totally removed (including the brain)? [closed]

I guess humans could live without just the right lobe of the liver or the right brain. Could a person without the whole right side of body survive? The left brain controls the right side of the ...
0
votes
1answer
38 views

Global Acidification or Warming [closed]

Which poses the greater threat to ecology Global Ocean Acidification or Warming?
3
votes
1answer
96 views

Looking for protocol to produce a drosophila primary cell line

I'm looking for a general (and easy, this is going to be for an undergrad class) protocol to isolate and culture primary cells from fruit flies.
4
votes
1answer
120 views

Main mechanism of the evolution of sexual dimorphism

Sexual dimorphism is very common and (normally) requires the evolution of sex-specific genetic variation/regulation so the genetic correlation between the sexes can be <1. Is there consensus as to ...
1
vote
1answer
159 views

Calories burn rate calculation — scientific studies

There are many online calculators for measuring walking/running/bicycling calories burn rate. They differ in input parameters like some might need my weight as well as height and some don't. Almost ...
1
vote
2answers
36 views

Deduce length order of 4 decapeptides based on the Ramachandran plot

I have stumbled upon the following past exam question: 4 decapeptides A, B, C, D, made only of glycine residues, have different conformations, and the phi and psi angles of individual peptides ...

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