1
vote
0answers
16 views

how to get truseq's gel size selection when preparing libraries for exome enrichment?

i would normally use a 6 minute fragmentation as quoted by agilent but this gives post exome enrichment libraries of around 300bp or slightly over. Truseq want libraries to be 100bp larger. i am ...
1
vote
1answer
61 views

PCR directly on DNA binds to Ampure XP

During the library preparation it's possible to conserved Ampure beads during the different enzymatic reaction (it's the with beads strategy for improving yield, Fisher et al. Genome Biology 2011). ...
1
vote
1answer
16 views

how to re-sequence a few Mb of genomic sequences?

If I want to re-sequence a known part of the chromosome (we know the reference genome sequence) of ~1Mb to find the possible mutations (SNP or INDEL) that caused a certain phenotype. What is the best ...
2
votes
1answer
26 views

Separation of closely-sized isoforms

I have to separate two proteins of 86kDa and 80kDa respectively, however, I just cannot get a decent separation even in 6% polyacrylamide gel. To make matters worse, these two proteins are isoforms ...
1
vote
1answer
44 views

Rosetta strain with chaperones for protein expression?

I am trying to purify a protein, and I was wondering if it is reasonably straightforward to obtain E.coli cells containing: -pGroe plasmids expressing chaperones. -Rosetta plasmids with codons that ...
-1
votes
1answer
61 views

How does a multicellular, eukaryotic body treat heat-resistant pathogenic bacteria?

How does the said body treat heat-resistant pathogenic bacteria? If fever is the body's response to foreign microbial invasion, then what happens if the bacteria is heat-resistant but the body's own ...
0
votes
0answers
54 views

General time reversible model of evolution and Felsenstein model

I would like to get suggestions for the books related to General time reversible model of evolution and Felsenstein model etc. Specifically the mathematical treatment of these topics and concepts ...
0
votes
1answer
26 views

Intro Bio question: dihybrid punnet square

Today we had our exam. There was a punnet square for two genes. and when I multiplied , for example, Ry × rY I wrote the answer as ...
5
votes
2answers
174 views

How does the eye know whether to focus further out or nearer in order to bring a blurry object into focus?

If the eye sees an object, but the object is out of focus, the eye could be focusing too near or too far. How does the eye (or the brain) distinguish one situation from the other? How does it know ...
6
votes
3answers
606 views

What makes DNA sticky-ends sticky?

When restriction enzymes jaggedly cut double stranded DNA it results in so called sticky ends. What is the substance that makes the DNA sticky?
2
votes
0answers
53 views

Modified Mendelian Ratios Problem

I'm studying modified Mendelian ratios. I've got a theoretical problem that I'm stumped on: A species of bird may have normal wings, or a mutation that causes frazzled wings. I do 15 identical ...
3
votes
1answer
95 views

Why do we have two of some organs, but not all?

We have two eyes, but we don't have two hearts. Why do humans have two of some organs, but not all?
4
votes
1answer
38 views

A few questions regarding immunology [closed]

I know that there is a variable region on antibodies which can recognize a wide variety of antigens, and that germinal centers create more "fit" antibodies to respond to an infection. So I was just ...
8
votes
3answers
91 views

If my brain lost all of its activity for a moment, would my memory be gone too?

I can't remember which question it was, but in the past here, it was explained to me that memory is actively stored in the brain, rather than "physically". Meaning, memories are made up of the brain's ...
2
votes
1answer
142 views

Why can't people talk while inhaling?

Why do we have to exhale in order to talk? From looking on Wikipedia, it seems like it has something to do with the glottis, but I'm not clear on the mechanism that makes speech sound so different ...
1
vote
1answer
44 views

Anesthetics, specifically inhaled anesthetics

I have had a look at previous inhaled anesthetics and many of them appear to be fluorocarbons. What could be the mechanism behind fluorine's anesthetic properties? Is it the specific bonding pattern ...
2
votes
2answers
65 views

Duration of selection and survival of the fittest

I feel there is a part of the theory of evolution I'm not understanding correctly or maybe I'm missing it, but would like cleared up. From what I understand, over time random mutations occur which in ...
9
votes
3answers
342 views

What causes feeling of feet falling asleep to be delayed?

This answer explains the sensation of extremities "falling asleep" as a result of sustained pressure on a nerve. The answer links to an external web page that says that the feeling "quickly goes away ...
6
votes
1answer
237 views

Why do some internal organs regenerate?

I have been reading about the human liver and zebra fish heart muscle having the ability to regenerate. It seems to me that these organs have very little chance to become damaged or worn out. At the ...
0
votes
1answer
25 views

If gene differs between chromosome pair does individual get a mixture of protein shapes?

Do diploids such as humans end up with a mixture of two different shaped proteins where the appropriate gene is expressed differently in the two halves of a chromosome pair or is there some governing ...
3
votes
1answer
46 views

What are limitations on the number of objects the eye determine at a glance?

Take two people Sam (average human) and Jack. Jack says to Sam "I'm going to show you some skittles (or other object) and I want you to tell me as quick as you can how many I'm holding." He opens ...
1
vote
1answer
74 views

(how) is it possible to choose the biological sex of a child? [closed]

I recently read of a study that investigated the ethics of child's biological sex choice in humans, and now I want to find out how this can/could be done. Does anyone know of scientific papers or ...
3
votes
1answer
206 views

How is satiety measured?

I am aware of satiety only through experience, rules-of-thumb and possibly myths. For example: white bread is not filling, a pasta meal can be filling but because we "burn" carbs quickly pasta itself ...
0
votes
0answers
48 views

Are ipratropium and tolterodine parasympatholytic?

They are nonselective cholinoblockers and antimuscarinic. Other cholinoblockers of parasympaticus, which I know, are parasympatholytic such as atropine, butylscopolamine, trihexyphenidyl, titropium ...
1
vote
1answer
75 views

Low copy numbers of plasmids

I have a plasmid with the P15A origin which apparently has a low copy number (see here). This would explain why my purification yeilds for subsequent digestion are low (gel shows the plasmid after ...
0
votes
1answer
101 views

Differentiation of norepinephrine and epinephrine in indications

Norepinephrine is less beta2 adrenomimetic than epinephrine so more selective so less bronchospasm so may be therofore better in treatment of cardiac failure and different shocks. However, I am not ...
1
vote
0answers
34 views

How do you accurately measure anguiliform (eel) locomotion?

In one of my courses, we were discussing a paper by Muller and van Leeuwen (2006) which made a lot of comparisons the differences between carangiform (mullet) and anguilliform (eel) locomotion. While ...
1
vote
1answer
35 views

Is there a stem cell dye for education purposes?

I need a dye that will stain stem cells (for this purpose the stem cells will proquired from chicken bone marrow). This will be an educational hands on activity for young teenagers so ideally the dye ...
2
votes
3answers
134 views

Is there an online gene library? [closed]

Is there an online library that includes all known genes in stored in their nucleotide form of all living organisms? Note I am not necessarily looking for a human only database. If such a database ...
0
votes
2answers
773 views

Purifying a linear plasmid after restriction digest?

I expressed a yeast vector in E.coli and purified about 13µg of it. I then linearized it using a restriction enzyme, and attempted to gel purify it. I attempted this twice. The gel showed a clear ...
0
votes
1answer
30 views

How can Pyridostigmine have the indication of Myasthenia?

I am thinking how pyridostigmine can be used in the treatment of myasthenia gravis. Its similar compound (neostigmine) is also anticholine esterase. This compound has the indication of myasthenia ...
4
votes
2answers
175 views

Can the human eye distinguish colors in the periphery?

In the back of my mind I have the idea that human eyes can't notice the color of objects in the far periphery, and that any subjective perception of colors is done by the brain that tries to fill in ...
1
vote
2answers
2k views

Theranos blood test's Specificity and Accuracy?

I am studying the limitations of Theranos device. They have 238 documents in Google Patents Search (Inassignee as Theranos), here. Which patents are relevant for their device? They have 70 tests ...
1
vote
1answer
24 views

allogeneic organ transplant and the immune response

What happens when an allogeneic organ transplant is performed on an immunocompetent recipient vs. when it is performed on an immunosuppresed recipient using a donated organ with immunocompetent cells? ...
1
vote
0answers
16 views

What mechanism prevent Colchicum Autumnale from being affected by Colchicine

Colchicine is a chemical usually used to cause polyploidy mutant by inhibiting chromosome segregation. It is synthesized in the Colchicum Autumnale. But what mechanism prevent C. Autumnale from being ...
0
votes
1answer
95 views

How does anger relate to blood pressure?

Anger is an emotion generated by neural processes in the brain and is associated with elevated blood pressure. How can an emotion, which is totally related to brain, result in blood pressure changes?
12
votes
2answers
2k views

How was birth control realized in ancient days? [closed]

In ancient days, there were no birth control methods like condoms or contraceptive pills available. How did they control pregnancy?
3
votes
1answer
89 views

How to inhibit formation of specific antibodies (to antisera)?

Is there a way to inhibit an antibody response to a specific antigen using immunosupression? I am interested in reducing the anti-antibody formation to animal antibodies such as murine antibodies in ...
9
votes
1answer
131 views

How big should the human population be, as predicted by body mass?

I would guess there is a theory in biology which states that the population size for a given species is inversely proportional to the body mass of individuals in that species. In other words, there ...
8
votes
1answer
106 views

Is our color vision calibrated to sky, vegetation, and blood?

Our color vision is based on three types of receptors (cones) which are sensitive to three distinct locations on the spectrum: 420–440 nm, 534–555 nm, and 564–580 nm. We label them "red", "green", ...
1
vote
2answers
77 views

human anti-mouse antibody

I have heard about human anti-mouse antibodies (HAMAs) and read that HAMAs neutralize murine antibodies, therefore decreasing the effectiveness of those murine antibodies. Is this true that HAMAs ...
1
vote
2answers
163 views

Why only female mammals have well developed mammary glands?

In course of evolution (possibly), mammary glands became vestigial in male mammals, but became fully developed in females. Is there any plausible explanation for this characteristic?
0
votes
0answers
25 views

Are there any mammals whose males can feed with milk? [duplicate]

Are there any mammals whose males can feed the offsprings with milk from the breasts?
1
vote
1answer
24 views

Flicker fusion threshold for insect eyes

I searched on bio-numbers for flicker-fusion threshold of insect eyes in general and for flies in particular. Ruck, 1961 gives values for some flies. Is there any database maintained for these values? ...
0
votes
1answer
35 views

Can the same protein be represented by primary,secondary,tertiary structure? [closed]

As my book says: Protein can be represented by 4 structures. The primary structure represents the main chain and positions of amino acid residues. But actually, protein is not a rod but rather a ...
0
votes
1answer
101 views

What is the charge on oligonucleotide 5' pGpGpApCpT 3' at pH 7.00?

What is the charge on the nucleotide 5'pGpGpApCpT 3' @ pH 7.00? I thought adenine has 1 NH group and Guanine has NH and ...
0
votes
0answers
14 views

More vectors for inducing neurodegeneration (reduction in synaptic plasticity) in D.melanogaster

I've just finished a project on loss of synaptic plasticity in Drosophila melanogaster larvae with uas control gal4 sensor for cAMP expressed in the motor neurons. I induced neurodegeneration through ...
3
votes
2answers
231 views

What does “chlorophyll photosynthesis peak” mean in relation to photon wavelength?

When reading about how green / leafy plants work, I saw that they have chlorophyll A & B, which allow the plant to use the energy from light by capturing and transforming. When reading about ...
2
votes
1answer
84 views

How to manage fat-gluten oxidation in celiac disease?

Assume you have been in non-gluten diet 20 years. You built mass 8 mass with substances containing gluten (endogenous gluten stored in fat). Then, celiac disease is diagnosed. You have been 3 ...
2
votes
1answer
54 views

Suggestions for self-studying experimental techniques

I would appreciate any suggestion regarding self-studying experimental techniques used in biology for a theoretical scientist (candidate). Maybe I should be more specific. I'm a biology major, but ...

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