2
votes
1answer
95 views

How does the MMR vaccine affect lymph nodes in preventing measles?

I am trying to understand this statement about the Measles part of the MMR (Mumps, Measles and Rubella) vaccine Measles prevention: MMR (AB protect during primary and secondary viremia) Measles ...
3
votes
4answers
1k views

Bad Eyesight and Evolution

Why do many humans have bad eyesight, such as near-sightedness, which hampers performance in a wide variety of tasks? Shouldn't there be evolutionary pressure towards better eyesight?
14
votes
1answer
1k views

What do viruses do during incubation period?

For example, there is an incubation period of around 1 to 3 days for common cold, and that of AIDS can range over to decades. What do viruses do actually do during the incubation period? What ...
1
vote
1answer
63 views

Conclusions from hybridization results

A double stranded DNA was denatured in a mixture that included mRNA from a gene in the segment. The mixture was then cooled to promote RNA and DNA hybridization. The following figure the results. ...
1
vote
1answer
64 views

What does “tumour budding” mean?

tumour budding, lymphocytic infiltration and resection margins are established factors that influence the outcome of colorectal cancer (1) In this context what does "tumour budding" mean? Reference ...
2
votes
1answer
116 views

Steps to confirm if predicted miRNA is good or bad

I aligned all miRNAs available to the supercontigs of a particular genome with certain parameters (e value of 0.01 and a word match of atleast 7 as suggested in this paper). I have also isolated the ...
1
vote
1answer
51 views

Anti-parallel DNA code operons

Coming from a software engineering standpoint, suppose I have a string of code like so: ... 5'-ATAGAC-3' ... ... 3'-TATCTG-5' ... Assume the above code is part of a larger segment. Now, reading ...
1
vote
1answer
164 views

Breathing under water

Why can fish breathe under water but land mammals can't? How can fish extract oxygen straight from water but humans can't?
7
votes
1answer
109 views

How do animals perform detailed active camouflage?

We often see videos of octopuses and chameleons changing their color to suit their surroundings. If it was a simple color change from white to red, it'd be understandable, but some of these animals ...
5
votes
1answer
87 views

Selective Androgen Receptor Agonist

I'm looking for an inducer that strongly activates the androgen receptor, but not the glucocorticoid receptor that is not DEA regulated. I know that SARMS (Selective Androgen Receptor Modulators) are ...
3
votes
1answer
156 views

What happens if someone with mutations to alcohol dehydrogenase (ADH) drinks alcohol?

ethanol then doesn't get converted to acetaldehyde. in fact, could someone KO'ed for ADH be resistant to methanol poisoning?
0
votes
1answer
634 views

Genes, chromosomes, base pairs and the 23 pairs

OK so I'm a bit confused. Does a chromosome consist of genes and do genes consist of DNA? What about the 23 pairs in sexual reproduction? I can't remember what the pairs consist of
1
vote
1answer
31 views

Relation between respiration and concentration of citric acid

A and B are 2 reactions. If there is an excess availability of citrate, then which of the above reactions will prevail? I know that citric acid is formed when oxaloacetic acid reacts with acetyl ...
0
votes
1answer
41 views

Feedback affecting myocyte metabolism in humans

I understand that there are several reserves available to muscle that can be tapped for ATP, and that each reserve is being used to some degree at all times. Are these reaction rates purely due to ...
2
votes
1answer
58 views

What is inside IDL (intermediate density lipoproteïn)?

I am studying about the endogene lipidcycle in the human body and I know that VLDL (very low density lipoproteïn) is made in the liver and that it contains triglycerides and cholesterol from your food ...
3
votes
1answer
80 views

Biological advantage of electric synapses

Electric synapses are synapses that do not process information but simply foward one action potential from one neuron to the next. There are no neurotransmitters, no inhibitory and exitatory ...
3
votes
2answers
520 views

Initial population when i count backwards?

My question is dealing with how many ancestors it took to produce me: --> to produce me it took 2 people (my parents) = ($2^1$) people = 2 --> one generation further included = ($2^1 + 2^2$) people ...
3
votes
1answer
350 views

What is “bacto” peptone?

Standard recipes for yeast medium often include "bacto-peptone". Is this the same as bacteriological peptone? Is there an authoritative source that spells it out?
2
votes
3answers
934 views

If the top epidermal layer is burned away, what is it replaced with?

If the squamous (top) layer of epidermis, or skin, is burned or damaged in another way, will it then be replaced by the next layer of below? Also, from where does the basal membrane originate? Does ...
2
votes
0answers
28 views

How closely correlated is the level of an snRNA with the level of its corresponding snRNP?

Let's say I am growing cells under two conditions, and let's say I measure U1 snRNA levels in both using digital PCR. If the U1 snRNA level is reduced in one sample, how safe is it to say that U1 ...
3
votes
2answers
93 views

Cancer growth and cell division [closed]

I am confused about the prerequisites for cell division and cancer. Which of the following is necessary for the cell cycle to progress? Hormones Growth factor Cyclins Cyclin dependent kinases ...
1
vote
0answers
33 views

Why do some fruits have their seeds disintegrated

Sometimes I'd come across a Lychee or a Naseberry whose seeds are kinda disintegrated.. in a thick powdered form, either completely or partially. What could cause such a thing? And is the fruit with ...
1
vote
1answer
129 views

Meaning of “auto” in trans autophosphorylation?

Why this process called "auto"? Is it because each tyrosine kinase receptor subunit of the RTK dimer has the ability to phosphorylate tyrosine or other amino acid residue present in other subunit of ...
8
votes
1answer
389 views

List of np-hard problems in biology/bioinformatics

I'm not sure if this is the right place for this but... I am looking for a list of computationally "hard" problems such that if a problem from this list could be solved effectively, it would be ...
1
vote
0answers
68 views

Regulation of Cra protein level in E coli

Catabolite Activator/Repressor, Cra protein (formerly known as Fructure Repressor FruR) plays a significant role in central carbon metabolism of E coli. Its activity is inhibited by ...
13
votes
2answers
591 views

Are there issues with filling PCR tubes to capacity?

I'm planning to scale up a PCR reaction, and I'm wondering if filling the PCR tubes to the maximum volume of 200 ul would be a problem. It would mean a lot less pipetting as I would only need 1/4 of ...
0
votes
1answer
311 views

What the difference between an inverted and everted retina?

I'm looking specifically for examples and comparisons, because the definitions of inverted and everted are remarkably similar; e.g. from Dictionary.com/Reference.com: everted verb (used with ...
14
votes
3answers
397 views

Can plants get cancer?

I can't think of any reason why plants wouldn't be able to get cancer, but I've never heard of a plant growing a tumor. I've also never seen a plant with a noticeable abnormal growth. Can plants get ...
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 ...
2
votes
1answer
83 views

How was Restriction Site of EcoRI sequenced?

The sequence of restriction site of EcoRI - GAATTC was identified in the early 1970s, before Sanger Sequencing was invented.(1977) How was the restriction site of EcoRI sequenced ?
2
votes
1answer
134 views

Can a brain be transplanted?

Is it possible to transplant a brain and would it keep the memory? If not, what would be the prerequisite to transplant one?
1
vote
1answer
49 views

Distribution of fitness in wild populations

If I get out in the wild observe wild populations and measure the distribution of fitness $f(w)$ in a given population. What will I find out? Will I observe a Gaussian distribution, a Poisson ...
2
votes
1answer
106 views

Exercise vs stimulants, which is more effective for promoting concentration?

Stimulants are the first choice for treating ADHD. But we also know that exercise helps to improve concentration. We know that both stimulants and exercise increase bloodflow to muscles and to the ...
1
vote
1answer
3k views

Why do we suffer abdominal pain after we get very angry or stress?

You also realize probably, when we get so much anger or high levels of stress, after some point we have terrible stomach ache, like really heavy pain. Why is that? How stress or anger can effect our ...
3
votes
3answers
117 views

Restriction endonucleases are found in?

Quoting from : Scientific American July 1975 The Manipulation of genes by Stanley Cohen : Restriction endonucleases (and modification methylases) are widespread in microorganisms; genes for ...
3
votes
2answers
428 views

What is the fastest marine mammal?

When I did a research, most of the sources say that orca is one of the fastest. But I could not find a source that says it is actually the fastest. Some sources say that Dall's porpoises rival orcas ...
19
votes
3answers
3k views

Were there any flying dinosaurs?

I've seen some articles which came in contradiction with each other. The first article was talking about flying dinosaurs, dinosaurs with feathers and so on. A couple of other articles are talking ...
1
vote
1answer
104 views

What is the evolutionary reason behind human preference for salty foods?

It's been established that food palatability is related to it's caloric density. This hypothesis is used to explain why humans are partial to sugar and fat. But it is also said that humans are partial ...
2
votes
6answers
238 views

Sequence analysis software suites

I have used DNAStar laser gene and VectorNTI in the past for cloning, primer design, sequence alignments, etc but no longer have access to these. Are there any comparable replacement suites or what ...
2
votes
1answer
2k views

What is the difference between these terms: clade, monophyletic group and taxon?

Wikipedia definitions for these terms are pretty similar: http://en.wikipedia.org/wiki/Clade http://en.wikipedia.org/wiki/Monophyletic_group http://en.wikipedia.org/wiki/Taxon They sound like the ...
2
votes
2answers
160 views

Why isn't phosphorus or nitrogen a limiting nutrient for animals?

Nitrogen and Phosphorus are usually the limiting nutrient for plants, especially for algae. Phosphorus is used for DNA, ATP and phospholipids, and Nitrogen is used for pretty much every protein a ...
5
votes
3answers
332 views

How does a biologist decide when she has enough results to publish a paper?

Biology is so exciting! Answering a question leads to thousand more questions! There is no limit to how much one kind find out about a phenomena… So I have always wondered how someone can ...
3
votes
1answer
52 views

Is there a superterm combining “animal line” and “cell line” in disease models?

Biologists researching diseases will frequently use animal models. The way I understand it, there are species of animals, such as "mouse", and lines of mice, such as ...
0
votes
1answer
41 views

Protoporphyrinogen (IX) formation in heme synthesis

This picture shows one of the steps of heme synthesis. In this step two propanoate groups of coproporphyrinogen III are decarboxylated to form protoporphyrinogen IX. The enzyme that catalyses this ...
3
votes
2answers
235 views

Could humans theoretically see infrared better than regular light?

I have noticed that in infrared film, people's eyes reflect that light within their eyes much like nocturnal animals (and many other animals for that matter) do with regular light. I know that this is ...
7
votes
1answer
185 views

What species is this mammal?

I saw a mammal that looked like a large squirrel. I haven't seen anything quite like it. Can you help me identify it? Squirrel-like, "hunched over" posture. It was too large to be an eastern ...
2
votes
0answers
26 views

Do axon grows after cutting/damaging of some of its part?

Do axon grows after cutting of some of its part to near original place? Do axon restores after local damaging of some of its part? I take https://class.coursera.org/neurobio-001/ classes and learn ...
1
vote
1answer
153 views

Transverse diffusion of lipids in red blood cells

The membrane of a human erythrocyte has polarity: Phosphatidylethanolamine and phosphatidylserine are predominantly on the inner side. Phosphatidylcholine and sphingomyelin are predominantly on the ...
8
votes
1answer
161 views

How can antibiotics damage the ear?

What is the mechanism by which aminoglycoside antibiotics (such as streptomycin and gentamicin) damage the mechano-sensory hair cells of the auditory and vestibular system? (Could this be seen as ...
7
votes
1answer
185 views

Is fluoride toxic, and how worried should I be about it?

A recent flurry of "fluoride is bad!" posts are appearing on my social network news feeds. Usually I can simply ignore them after a brief look, but this one, stemming from a recent article in The ...

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