5
votes
2answers
161 views

Viruses: Adaptation to a new host through repeated host jumps

A friend told me, during a 3 minute discussion, that viruses that are endemic in host $A$ and make repeated jumps to host $B$ but can't be transmitted between individuals of species $B$, may slowly ...
2
votes
1answer
512 views

What is optical density in Lowry's protein estimation method?

I have a few questions: What is an OD value? Why do we use blank solution in Lowry's protein estimation method? If The OD of a protein is 0.01, what does it mean? Thanks in advance.
1
vote
2answers
114 views

Modern alternatives of DNA footprinting

Since DNA footprinting is an old method I thought there may be some more recent and effective methods to identify a DNA sequence, do you know any of them?
3
votes
1answer
65 views

What happens to human dopaminergic reward system once a teenager becomes adult?

I've recently heard a podcast which explained teenage impulsivity and novelty seeking in part by "Lowering the baseline dopamine activity in the reward system" "Increase in dopaminergic reward in ...
4
votes
2answers
351 views

Can animals make their own unsaturated fatty acids?

I know that animals can't make poly-unsaturated fatty acids (PUFA) and so require them from dietary sources. For eg.Omega -3 and Omega 6 fatty acids. My questions : Can animals synthesize other ...
1
vote
2answers
91 views

PDB file for Osteopontin (SPP1)

I am looking for PDB file for Osteopontin (SPP1). The entry- 3CXD shows the structure of an Osteopontin antibody, not of the protein itself. Thanks
3
votes
2answers
312 views

How are two species with similar phenotypes identified as different?

How are two species with similar phenotypes identified as different? Have two different individuals that were thought to be different species ever been determined to be from the same species ( or ...
2
votes
1answer
59 views

About stem cells and Cancer

Do stem cells have an apoptosis mechanism and , if they do could this be used to repair the cell self-destruction pathways in a cancer cell?
3
votes
1answer
24 views

Polarized epithelium and localization of ion channels

I'm trying to learn more about polarized epithelial cells of the gut. I am familiar with classic brush border transporters localized to the apical memebrane to facilitate nutrient absorption. I am ...
1
vote
1answer
293 views

Identifying structures from anterior end of dissected prawn

Note: This image might be disturbing. I want to know what the red and the black structures (directly posterior to the red structure) are. I guess it's the heart.
1
vote
1answer
52 views

Any forms of pneumonia that can be caught?

I am aware of the fact that there are several different types of pneumonia. However, I am wondering if any of these types of pneumonia are contagious from person to person. Is this possible?
0
votes
1answer
885 views

Identifying internal structure of dissected prawn

Note: Some of the images might be disturbing. I have dissected prawn for the first time. Would like your help in identifying some structures . This is the dissection of the posterior part of the ...
3
votes
1answer
105 views

What type of insect is this? [closed]

ery bug 1]1 What insect are these? Found them indoors. No wings, just crawling on the walls.
3
votes
1answer
113 views

Identifying internal structures of dissected fish

Note : Images displayed below might be disturbing to some people. I have dissected a fish for the first time ! I have some idea of what some of the structures might be but I am not sure and so would ...
2
votes
1answer
84 views

Saliva test for Toxoplasma gondii?

I am trying to find some reliable gene kit by which you can rapidly test Toxoplasma gondii. I am not sure if it exists. I have an intuition that some tests done during 90s-00s on this species had high ...
2
votes
1answer
487 views

Why are hybrids infertile?

Let's take a quote from Wikipedia about zebroids. Donkeys are closely related to zebras and both animals belong to the horse family. These zebra donkey hybrids are very rare. In South Africa, they ...
3
votes
1answer
152 views

Biological meaning/interpretation of clustering coefficience

I have been looking for some time to find an answer to the following question. I would be grateful for any help/advice or directions. I work very frequently with large number of proteins and assess ...
12
votes
3answers
328 views

How does a person get AIDS?

I am inquisitive to know about how a person contracts AIDS. Among the common masses it's still the belief that having sex with multiple partners causes the disease but that is not the case when read ...
3
votes
1answer
527 views

Why do cockroaches burst from soapy water?

(careful, disturbing!) I was experimenting with some stray cockroaches that ended up falling in my bath tub overnight (there is currently an infestation undergoing in my apartment building) and I ...
9
votes
1answer
144 views

Why do so many people have group O blood?

Please forgive me in case my question wouldn't make much sense. I was reading about ABO blood groups on Wikipedia, where I learnt that O is a recessive allele, and that it seems the A allele predates ...
4
votes
3answers
329 views

Does anyone know a good software for producing tanglegrams?

I'm trying to look at relationships between parasite and host phylogenetic trees. I have done a bit of searching for a software in which to do this with, and I have tried using Dendroscope and ...
3
votes
1answer
361 views

How does chromosome cross-over occur?

I have heard that during meiosis, homologous chromosomes from each parent "cross-over", which enables the off-spring to inherit some alleles from the mother and some alleles from the father. The ...
1
vote
1answer
42 views

How does a blunt force stimulate histamine to develop early stages of inflammation?

I know that viruses and sharp forces can stimulate mast cells by cut or by a virus infecting them and then release histamine. How can blunt force do this and cause inflammation? It doesn't have the ...
9
votes
1answer
194 views

Seeing strange things in light

I have noticed that if you look directly at tubelight (I have only white ones in my home) and close your eyes little, you see little random shaped colourless things sometimes with slow speed and ...
0
votes
1answer
41 views

Metapopulation structure - book recommendations

What book would you recommend me to study: the dynamics of metapopulations, the structure of metapopulations, the evolution in structured metapopulations? I am not looking for an introduction ...
3
votes
1answer
97 views

Amino acid profile of GPCRs

You are studying cellular signalling through a newly identified GPCR. Specifically you’re working on a pair of newly identified GPCRs, GPCR-A and GPCR-B. Each binds the same small ligand, but ...
2
votes
2answers
107 views

chimeric sequences [closed]

I understand that chimeric sequence identification is done in results of sequencing projects to remove them and improve the quality of the output. I am unsure as to how they show up during sequencing. ...
2
votes
1answer
83 views

Do insomniacs yawn?

According to wikipedia, the jury is still out on the function a yawn serves. The article referenced above however writes to say Yawning most often occurs in adults immediately before and after ...
3
votes
2answers
91 views

Sequence alignment scoring

The following table is from Deonier's text Computational Gene Analysis at p. 152. This is an exercise in global sequence alignment and scoring of alternative sequences. The text proposed a solution ...
1
vote
3answers
190 views

Are hens and roosters the same species?

I know that one is a female chicken and the other is male chicken. Are the chickens laying eggs considered the same species as those that we use for poultry meat? Or, are they different sub-species, ...
1
vote
0answers
158 views

Effects of Genetic Drift on Linkage Disequilibrium

From what I understood of @Canadianer's answer here... Genetic drift randomly causes negative or positive linkage disequilibria, by changing allele frequencies through random sampling. Natural ...
1
vote
1answer
31 views

Could super-caffeinating somebody's bloodstream be dangerous?

I'm currently planning out an RPG based on Misfits. Basically young offenders get super powers. I want one of the villains to have a really lame power that they use to become incredibly dangerous. I ...
8
votes
2answers
570 views

Can a neuron make a synapse onto itself?

I was wondering if a neuron can make a synapse to itself? I suspect that it would be extremely unusual for a neuron to do this. Anyway, has anyone seen even a single instance of this? Is the process ...
2
votes
1answer
48 views

How are dental cavities different from body injuries?

I always had this question why dental cavities cause pain. I stumbled on this question on the reasons why dental cavities are painful. I have a followup question on how dental cavities are different ...
6
votes
3answers
106 views

Hebbian theory “fire together” clarification

Donald Hebb states it as follows: "Let us assume that the persistence or repetition of a reverberatory activity (or "trace") tends to induce lasting cellular changes that add to its stability.… ...
1
vote
1answer
44 views

psychological database with sequenced DNA records

I'm looking for an epigenetic database which includes for each example the psychological history of the persons DNA. Right now I can only find DNA and epigenetic databases. Sadly none of the databases ...
3
votes
1answer
140 views

Are people genetically predisposed to being interested in specific fields/ideas? How does specialization occur?

I'm not sure if I formulated my question well, but I'm curious about a couple statements made by Steven Pinker and and James Heckman. In this interview: ...
6
votes
5answers
3k views

Why don't we breathe nitrogen when it makes most of the air?

Why don't we breathe nitrogen while it makes most of the air? Why do we always tend to breathe oxygen, not hydrogen and nitrogen?
1
vote
1answer
75 views

Could the Warburg effect be used to starve cancer cells in situ?

What is wrong with the following chain of reasoning? Nearly all cancer cells rely on high rates of glucose uptake (upto 200 times more than normal cells). This is known as the the Warburg effect. ...
1
vote
1answer
108 views

What is the current molecular explanation of Mendel's pea cross?

With reference to the simplest Punnet square for Mendel's pea plant experiments it occurred to me that I could not connect the little I know about genetics to the little I know about molecules. The ...
3
votes
1answer
47 views

Preventing paracetamol overdose

Paracetamol overdose is one of the most common drug toxicities. It may be treated by intravenous N-acetylcysteine which replaces the glutathione that is used up in paracetamol metabolism to prevent ...
2
votes
2answers
51 views

In which direction plants' root grow in weightlessness? [duplicate]

As far as I know, roots of plants grow to the direction of Earth's gravity - this is called gravitropism. But what happens if plants are in space? Are they able to perceive gravity in state of ...
2
votes
1answer
4k views

How does a TOPflash/FOPflash assay work to detect beta-catenin protein expression?

I am reading an article (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3596711/) wherein a TOPflash/FOPflash assay is used to detect beta-catenin protein levels in a COS-7 cell line. I can't find a good ...
1
vote
1answer
217 views

definition of tempo and mode in evolution

I am reading Punctuated Equilibria: The Tempo and Mode of Evolution Reconsidered, which mentions the "tempo" and "mode" of evolution. I'm not familiar with the related literature and when I google the ...
2
votes
1answer
46 views

Definition of Linkage Desiquilibrium (LD)

According to wiki, linkage disequilibrium $D$ equals $$D = x_{11} - p_1\cdot q_1$$ where: $$ \begin{matrix} \text{Haplotype} & \text{Frequency}\\ A_1B_1 & x_{11}\\ ...
3
votes
1answer
62 views

How does tree resin capture arthropods?

In regards to a published paper of a spider about to make a meal out of a parasitic wasp (http://www.tandfonline.com/doi/abs/10.1080/08912963.2011.640399#.U1kSV14gVBU), it reminded me of a issue I've ...
1
vote
1answer
53 views

Are bronchioles and alveoli covered by respiratory epithelium?

Which parts of respiratory apparatus are covered by respiratory epithelium and which are covered by other kinds of epithelium?
0
votes
1answer
36 views

Why rectus abdominis is not proximal muscle?

I am thinking this picture which shows proximal muscles. Why for instance pectoralis major, subclavius and rectus abdominalis are not included in proximal muscles?
1
vote
1answer
32 views

To have TBE vaccine during allergic times with mild asthmatic symptoms?

My assistant says that if you have asthmatic symptoms you cannot have TBE (Tick Born Encephalitis) vaccine, although you are living in the active zone of TBE. Cases mild allergic symptoms allergic ...
2
votes
2answers
762 views

Name of scientist who discovered lifesaving drug and chose not to patent it?

I recall reading about a 20th century scientist who made a life-saving drug that could have patented it and made millions. He chose not to and saved the lives of millions around the globe. I thought ...

15 30 50 per page