2
votes
1answer
43 views

Nicotine vs. Caffeine. Why is one more addictive than the other?

Both nicotine and caffeine are considered to be addictive substances. Why is nicotine more addictive than caffeine?
2
votes
2answers
58 views

introduction to Chip Seq

I hope this question is suitable for this site. I am concerned about the Chip experiment part so I think it should be okay. I am a Applied Math student starting to get into bioinformatics and so I've ...
2
votes
2answers
19 views

Gel Electrophoresis - loading dye and more

I'm a student new to molecular biology coming in from an eco-evo background looking for tips from you molecular pros! It seems that I'm running quite a few gels. The loading dye I'm using is Gel ...
2
votes
1answer
30 views

Why do the neuron pathways decussate?

I learn about the brain right now, and there are crossing of neuron pathways everywhere; in the thalamus, the medulla oblongata, the pyramidal tract... And I don't understand why? What is the reason ...
2
votes
1answer
31 views

Dominance/recessivity of new mutations

What is the distribution/probability density function (PDF) of recessivity/dominance of new mutations? I very welcome any partial answer that does not give the whole PDF but just some information ...
2
votes
2answers
50 views

Real time PCR normalization algorithm

When performing normalization of real time PCR results, I found two ways of doing it: In my lab they follow the next layout: $efficiency^{-(CT\ interest\ gene - CT\ housekeeping)}$ each time ...
2
votes
1answer
26 views

What stops telomerase?

The telomerase is an enzyme that adds telomeres. What stops the telomerase from adding too many telomere sequences ? What's the regulating mechanism ?
2
votes
1answer
19 views

Meaning of the word Oleracea

What does "oleracea", as appears in numerous plant species (scientific) names, mean? Examples: Euterpa oleracea, Brassica oleracea, Portulaca oleracea, Acmella oleracea, Spilanthes oleracea.
2
votes
1answer
175 views

Why can't ciliary muscles in the human eye relax like other muscles?

I had laser eye surgery a decade ago, but in recent years my eyesight has become significantly myopic. I consulted an ophthalmologist to see if this was eye strain because I work at computers a lot, ...
2
votes
1answer
53 views

Would expression of GroEL and GroES in erythrocytes be a potentially effective therapy for sickle cell disease?

Would expression of GroEL and GroES in erythrocytes be a potentially effective therapeutic strategy for sickle cell disease? Why or why not?
2
votes
3answers
48 views

Publicly available genotype data?

I am a statistician and I'd like to test my new method on biological data. For this I am looking for genotype data for a number of individuals. That is, I am looking for something like this: ...
2
votes
1answer
54 views

How much solar energy required to compensate food?

Just curious, how much solar energy can power an (herbivore) animal? Specifically, is it enough sunlight on Mercury (4 to 10 times brighter than on Earth) to "feed" a zebra? Will it be sufficient at ...
2
votes
1answer
31 views

Quorum Sensing in Vibrio cholerae

This is a figure summarising the quorum sensing mechanism in Vibrio cholerae. In this video by Bonnie Bassler, she explains how quorum sensing can be targeted to control infections. At 15:09 she ...
2
votes
1answer
66 views

No bands show up in gel electrophoresis, not even marker

I haven't seen any gel lanes in neither my PCR samples nor the marker itself when photographing them. This is not my first time performing 1.2% agarose gel electrophoresis. I see gel lanes when I ...
2
votes
3answers
68 views

Quantitative Differences : DNA and Gene

After HGP, we are not having many databases which consist of several notepad files of ATCG.... Can we distinguish quantitatively a given A,T,C and G stretch as DNA or Gene?
2
votes
2answers
128 views

Promoter in the lac operon

Here is the question: Suppose an experimenter becomes proficient with a technique that allows her to move DNA sequences within a prokaryotic genome. If she moves the promoter for the lac operon to ...
2
votes
1answer
49 views

What is the creature with the lowest neuron count that demonstrates cognition beyond reflexes?

I'm under the impression that nematode worms just perform the same scripted actions over and over again in response to specific stimuli. They have 302 neurons. Chimpanzees display problem solving ...
2
votes
2answers
70 views

Explanation of the terms “downstream signaling” and “upstream signaling”

In molecular biology, what's the meaning of the terms "downstream signaling" and "upstream signaling"? What's the difference between them?
2
votes
2answers
58 views

Is there any evidence of increased life expectancy for animal species?

Life expectancy for human has significantly increased during the last century or so. We all know that there are many reasons that are not linked with "evolution", but I am wondering if such change in ...
2
votes
1answer
65 views

Isopropanol precipitation of DNA - duration and magnitude of cold storage

DNA prep protocols often include a final precipitation step with alcohol, often isopropanol, where the DNA must be kept in the alcohol, at a low temperature such as -20C or -70C, often overnight. ...
2
votes
1answer
64 views

Does this equation have a typo? (Systems Biology, singular value decomposition) [closed]

I'm reading a systems biology paper, and I'm suspecting there's a typo in an equation, but I want to make sure. The article is "Systemic metabolic reactions are obtained by singular value ...
2
votes
2answers
43 views

Do humans have a “dominant” neurotransmitter system/sensitivity within their brain?

I've recently heard a podcast, in which Dr. Helen Fisher suggests that there are "4 broad personality types", and each one is associated with a particular neurotransmitter: The corresponding ...
2
votes
2answers
45 views

Connection between genes and pathways

I am reading about a paper about inferencing pathway information in cancer cells. Authors refer to ERBB2 as a gene and a pathway. I don't have solid biology background. What exactly means when we ...
2
votes
2answers
78 views

Is it possible to create an experiment in house conditions to prove the existence of germs?

I realise that the best way to prove the existence of germs or single-celled organisms is by looking at them through a microscope. But I don't have a microscope at my home, how can I design an ...
2
votes
1answer
42 views

How good is information transfer between the hemispheres of the brain?

I sometimes listen to lectures on my phone using ear buds, but occasionally with only one ear bud in. Is the other half of my brain losing out on any aspect of the lecture? Just how good is the corpus ...
2
votes
1answer
32 views

maximum # of generations possible in a population of cannibalistic rats

Assume a sufficiently large population of rats (to allow genetic variation and facilitate inbreeding) in a place with abundant water, sunlight, shelter but no food. For how many generations can this ...
2
votes
1answer
39 views

Evolutionary conservativeness

List the following proteins in the order of decreasing evolutionary conservativeness of their primary structure: Somatotropin. Catalytic subunit of a DNA – polymerase. Histone H1. ...
2
votes
1answer
38 views

Mites on ginger root

I was just looking at some mouldy ginger found in the fridge under the microscope and was horrified/delighted to find (what looked to be) mites growing in it. I have searched the web and can only find ...
2
votes
1answer
34 views

What is mRNA expression level?

I cannot find clear explanation of what is mRNA expression level, and how to measure it. I would appreciate if someone explained it or gave a reference. Thanks!
2
votes
1answer
37 views

The arrangement of retinal cells?

The section of retina shows a layered arrangement of the various retinal cells. Starting from the inside (where the light strikes first) is the nerve fibre layer, ganglionic layer, amacrine cell ...
2
votes
1answer
522 views

Identification - What kind of animal leaves these tracks?

I live in the suburbs of Washington DC where it recently snowed. I was admiring all of the tracks left behind by wildlife of all kinds when I came across these prints, that I was unable to recognize ...
2
votes
1answer
27 views

Difference vector target and genomic target

In Pfu turbo DNA Polymerase AD information sheet (and possibly in many other) different amplification targets are divided in Genomic DNA targets, Vector DNA targets and cDNAs. What is the difference ...
2
votes
1answer
77 views

Scrotal temperature and vascularization

The testes (at least in human males) are vascular organs, the vascularization extending even o the interstitial spaces of the seminiferous tubules. The function of the scrotal sac, is to isolate the ...
2
votes
2answers
162 views

Homework : Sodium Potassium pump

Why does sodium-potassium pump consume about 2/3 energy of a cell ? A.maintains appropriate membrane potential B.helps in co-transport I think it should be A.
2
votes
1answer
279 views

Telomere shortening during replication

It is widely know that each cell cycle during DNA replication some fraction of the telomeres is lost, and this phenomenon is called the end replication problem. Well this is due to the fact that the ...
2
votes
2answers
75 views

How does smoking, an environmental factor, cause cancer, fundamentally a genetic disease?

If cancer is fundamentally a genetic disease, how might an environmental factor such as smoking cause cancer?
2
votes
1answer
176 views

Population Growth Rate Question?

A population of 600 birds faced a problem of biological magnification resulting in a large number of deaths reducing their population to 350. But 230 births also took place and 21 birds immigrated ...
2
votes
2answers
56 views

Breakdown current for human body

If I am not mistaken, during exposure to electricity sources it is the magnitude of the current and not the voltage that kills the human body. If so, what is the order of magnitude of current that ...
2
votes
2answers
208 views

Do brain cells shrink during REM sleep or a lucid dream?

In this BBC news article a study shows that during sleep brain cells shrink to open up the gaps between neurons and allow fluid to wash the brain clean. But do the cells shrink and undergo the whole ...
2
votes
2answers
74 views

Sources for common laboratory Saccharomyces strains?

I'm used to working with bacteria - some of the more common laboratory strains sometimes come with an order from some vendors. What's the most convenient source to order common straings of ...
2
votes
2answers
185 views

How is RNA of retrovirus converted into cDNA?

The retrovirus (oncovirus) contains RNA. It also has a molecule called reverse transcriptase. This molecule transcribes RNA into cDNA. This cDNA is the DNA copy of viral RNA genome RNA has Uracil ...
2
votes
2answers
70 views

How did viruses learn to utilize the workings of a cell?

This is my first post here, so excuse me for its simplicity. Viruses can infiltrate a cell, overtake it and multiply. It has projecting fibers whose ends are shaped as kind of a "key" to a mobile ...
2
votes
2answers
116 views

Accuracy of a particular genetics test

I am a newbie in biology and I am simply trying to discover the field of genomics. Consider the question - Are genetic tests accurate? I don't believe they are as the genes may not provide the ...
2
votes
1answer
861 views

Why is FADH2 made instead of NADH in one of the reaction of Krebs cycle?

FADH2 is made in conversion of Succinate to Fumarate. Why is this so ? Why not NADH ?
2
votes
1answer
53 views

observed luminescence in a piece of plaice

A plaice fish bought for human feed has been cleaned and cooked. Some parts of the raw body have been left out of the fridge at about 22°C for about 15 hours. During the following night a ...
2
votes
2answers
72 views

Can the colour of skin change with age

Can the colour of skin change with age? Can a dark skinned person become fair or vice versa? Can Melanocyte production vary?
2
votes
2answers
67 views

Why does the mixture of infant formula with saliva provide an ideal breeding ground for disease-causing micro-organisms?

From: http://www.nal.usda.gov/wicworks/Topics/FG/Chapter4_InfantFormulaFeeding.pdf Discard any infant formula remaining after a feeding. The mixture of infant formula with saliva provides an ideal ...
2
votes
1answer
27 views

potency in preformed germ-line

In organism that have a preformed germ-line like Drosophila where germ cells are pre-allocated in the oocyte, are there technically no adult pluripotent stem cells since germ line cells can't be ...
2
votes
1answer
212 views

Human body power consumption in still state

I'd like to know what kind of power human body needs to maintain life, in still state (average daily power consumption of an average man is also of interest). In terms of watts. I've only managed to ...
2
votes
2answers
71 views

What are the statistical tools for distinguishing molecular analogy from homology?

Scientists have developed statistical tools that distinguish "distant" homologies from coincidental molecular homoplasy in extremely divergent sequences. What are these tools?How are they used ? I ...

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