All Questions

3
votes
1answer
144 views

What is the evolutionary advantage of regret?

Some motivational speakers may say that regrets are only useful to learn something from. What are the other advantages?
4
votes
0answers
83 views

Does Lucid Dreaming decrease the regenerative effect of sleep?

After watching this SciShow video on sleep, I wonder about lucid dreaming. Specifically: Does lucid dreaming and associated directed agency within Lucid Dreaming decrease the regenerative effect of ...
1
vote
1answer
184 views

How do proteins get into the blood stream?

So I'm asking this in reference to the injection of insulin, which is commonly done subcutaneously (in the hypodermis, a fatty part of skin). Now I know proteins usually get into the blood when ...
4
votes
1answer
82 views

Why do some women have menstruation-like spotting throughout their pregnancy?

An interesting question that was asked during a lecture about human reproduction: what is the biological mechanism behind some pregnant women getting monthly spotting that they mistake for a regular ...
4
votes
1answer
191 views

DIfference between diversification and differentiation

In Adaptive dynamic : what is the difference between Ecological Differentiation and Ecological Divergence ?
1
vote
0answers
59 views

How common is complete heterochromia?

How common is complete heterochromia? (One iris is a different color from the other) Are there any statistics available for this? If no, why not?
1
vote
1answer
185 views

Can two denatured DNA strands reassociate?

What matter if I increase the temperature to 95°C. So double-strand DNA denatured into two ssDNA, and then I decrease the temperature to room temperature. Are they able to reassociate after ...
4
votes
1answer
388 views

What are the advantages and disadvantages of being ambidextrous?

What are the advantages and disadvantages of being ambidextrous? We have two hands and we nearly can't use one and this seems like a weakness, and a stupid one when you first think about it. But ...
3
votes
2answers
208 views

Why is there such an argument about evolution?

DISCLAIMER: I am a Christian, although I happen to believe that some form of guided evolution via natural selection is God's mechanism for creation. Now to my question, which is related to my ...
1
vote
1answer
70 views

(Web)app to search metabolic/signalling pathways

I'm looking for an application where you can find pathways by selecting a chemical occurring in it. So, for example, selecting 6-phosphogluconolactone brings up the pentose phosphate pathway or any ...
1
vote
1answer
71 views

DNA and gene activation

As far as the genetic content of each cell is concerned I have read to my satisfaction that all cells of a person's body except the red blood cells (with no nucleus and so no genetic message) and the ...
1
vote
1answer
82 views

How do I compare the variance of a distribution of species in one area versus another?

It's possible that this question is better suited for stack overflow, but I think the ecologists on this site might be better equipped to answer it. I'm trying to study two geographically-isolated ...
2
votes
1answer
164 views

Independence of Light independent reaction in photosynthesis?

Inspired by a question asked to me by a classmate, I have the following question about Light-independent (dark phase) reactions in photosynthesis:- Let us suppose an algae sample was exposed to ...
4
votes
1answer
221 views

How much does the Hayflick limit/telomere length vary across taxa and within humans?

Since they seem to be quite connected, I'm curious if anyone knows of research comparing the Hayflick limit (and presumably by extension telomere length) between different taxa. I've heard the ...
0
votes
1answer
28 views

What happens between making a DNA library and screening by nucleic acid hybridization?

I understand how a plasmid library is made and how each clone is put on the nitrocellulose membrane and nucleic acid hybridization is done. What I don't understand is how each clone is "identified" ...
0
votes
2answers
60 views

Telomeres in cloning experiments

In whole animal cloning ( eg. Dolly ) the nucleus is taken from a somatic cell. So isn't shortening of telomeres a problem ?
1
vote
1answer
237 views

Can sugar alcohols, and glycerol in particular, cause intoxication?

I'm mostly curious about glycerol, which I use as a sweetener. I've been told that it can cause intoxication, because it is an alcohol. Is this true? If so, are there any good sugar alcohols which ...
1
vote
1answer
296 views

Recombination frequency, linked genes, and independent assortment

Gene R is genetically linked to gene T with a recombination frequency of 0.3. Gene T and gene X assort independently from each other. Your colleague tells you that gene T and gene X reside on the same ...
1
vote
0answers
32 views

Transduction with P1 lysate prepared from strain that is proC::Tn10

If I do a transduction with a P1 lysate prepared from a strain that is pro*C*::Tn10 and the recipient is wild type, will all my recombinants be ProC- and Tet resistant since the Tn10 is in the proC ...
2
votes
1answer
251 views

Orientations of codon and anticodon

So 5'-AUG-3' is the start codon on an mRNA transcript Does that mean that the tRNA anticodon is 5'-CAU-3'? Here, I see that the tRNA anticodon for methionine is UAC, and the chart doesn't specify ...
1
vote
2answers
66 views

How does promoter sequence affect initiation?

I don't know if this might have been highlighted in recent research, but a textbook I have states that "the exact way in which promoter sequence affects [transcription] initiation is unclear" I'm ...
1
vote
0answers
369 views

Interpreting graph of mitosis and meiosis

Note : Consider the y axis as 1,2,3,4(not 2,3,4) and x axis as time. Roman numerals should be considered from I-X ( some are not correct here ) Which stages show mitosis? My answer : III-V Which ...
1
vote
1answer
64 views

Why use DNA polymerase in making cDNA?

RT is capable of synthesizing a complementary dna strand ( as in HIV life cycle.) Then why is DNA pol used when cDNA (synthesizing the second strand of it ) has to be synthesized from mRNA ( For eg.to ...
3
votes
1answer
82 views

Assumptions of Hamilton's rule

Which elements of the following list are assumptions of the Hamilton's rule? Population structure (non-panmictic population) Additivity = Fitness of the heterozygote equals the mean of the ...
2
votes
1answer
63 views

How to identify active protein in a complex mixture?

I am trying to figure out how to identify which protein in a complex mixture is producing a certain effect. There is an assay for the effect, so anything (a fraction of the mixture) can be tested ...
4
votes
0answers
53 views

Reformulation of Hamiton's rule

Who (and in which article) was the first to reformulate Hamilton's rule using the letters $B$ and $C$?. See below comments on this reformulation. Hamilton, in his 1964's article gave a mathematical ...
4
votes
1answer
105 views

Why are transmembrane proteins difficult to crystallise?

I know that in vivo there are a lot fewer transmembranous proteins in general, and that they are produced at a lower rate than their free counterparts. This is mainly because transmembrane proteins ...
4
votes
1answer
110 views

Stability of helical strands of DNA?

The DNA molecules contain phosphate groups involved in $3'\rightarrow 5'$phosphodiester linkages. These groups, in the bonded state with deoxyribose, contain 1 negative charges ($\ce{3'-PO4^{-}-5'}$). ...
1
vote
0answers
24 views

Improving throughput of CFU plating?

In a separate question I've described my general experimental setup where I need to measure the number of live cells in a growing bacterial culture in a fairly rapid and high-throughput manner. In ...
6
votes
1answer
280 views

Alternatives to CFU plating for measuring number of viable cells?

I am hoping to measure growth rates of a bacterial culture in several growth conditions. I am concerned that these growth conditions may cause cell death, which would lead to a decreased ...
1
vote
0answers
13 views

Cytoplasmic determinants in amphibians

If cytoplasmic determinants are distributed before fertilisation then how can an amphibian's embryo, whose dorsal side is determined after fertilisation develop ?
1
vote
2answers
311 views

Gel electrophoresis question

Leena is a molecular biology student. She purifies two fragments of DNA, 800 and 300 base pairs long. These were obtained from a plasmid after digesting it with HindIII. Each of these fragments has a ...
4
votes
2answers
709 views

Are Asians more genetically homogenous than other races?

I've heard that Asians (I'm not entirely sure which subgroup was being referred to) tend to be more genetically homogenous than other races, with people of African lineage being on the other end of ...
7
votes
2answers
504 views

Do men have a higher genetic variance than women?

I've heard that with the distribution of our genetic code women have less variation on the bell curve than men. Is there any basis for this? It was my understanding that women have more genetic ...
2
votes
1answer
181 views

What species is this rabbit-like animal?

This image was included in something I was browsing through. It reminds me of my lion head rabbit, but the head shape doesn't match. Is this some kind of Siberian wild rabbit?
-3
votes
1answer
82 views

what significance is the moon? [closed]

Why is it that planets like Mercury, Venus and Pluto do not have moons? or how significant is a planet having even one moon? How does it affect the planet's ecosystem, especially seasons and periods? ...
3
votes
2answers
137 views

Hardy Weinberg Equilibrium problem

In a small tribal population, the frequencies of two alleles A and a at a particular locus were 0.3 and 0.7, respectively. However, not all the individuals with genotype aa could live up to the ...
1
vote
1answer
68 views

Niche overlap Index

I wanted to use the compana() function from the adehabitat package. I don't really understand the meaning of the data in the ...
1
vote
0answers
98 views

Praying Mantis (female) put sticky white stuff on wall of aquarium

Anybody know what this sticky white stuff is? She had a foot stuck in it; I had to help her get it loose. Was she purposely gluing herself there (perhaps in preparation for molting), or is she sick? ...
1
vote
2answers
96 views

Protein purification methods

Which of the following methods would yield the most purified protein fraction? A. Salt precipitation B. Charge separation C. Affinity purification The first one is the most commonly used, is it ...
4
votes
2answers
116 views

Is AT or GC content important in electrophoresis?

Will it make a difference in running speed if we run samples of same no of bases but different AT - GC content ?
7
votes
3answers
4k views

Deciding between chi square and t test

I am always so confused whether to do a chi square test or a t test in the sums given by my biostats teacher. Does anyone have a simple rule to decide this?
1
vote
0answers
29 views

What determines the ion concentration in the body?

I am looking at ions in the body and am a bit confused about the differences between ion pumps and ion channels, and how they interact with each other. I want to know what determines the ion ...
1
vote
0answers
66 views

DNA cloning with gateway primers

I tried to clone a 5 kb gene with few success. The primers used are this OLIGO start len tm gc% any 3' seq LEFT PRIMER 1 22 62.53 50.00 4.00 2.00 ...
1
vote
1answer
266 views

Energetics and Products of Pepsin/HCl Protein Digestion

What are the energetics of protein digestion during which the enzyme pepsin is "activated" (whatever that means) by HCl? I've looked and been unable to find anything like a chemical equation that ...
4
votes
1answer
158 views

Western blotting questions?

everyone. I've just been introduced to the procedure of Western blotting from my reading, though I'm not entirely sure about some points. I'd appreciate it if someone could help me with this. What ...
1
vote
1answer
42 views

How cotranscription events affect splicing?

I want to know how and how often does cootranscription takes place? Can transcription regulators influence splicing during cotranscription?
0
votes
1answer
56 views

Electrophoretic mobility of isozymes

If isozymes are seperated using electrophoresis, which of the following will be the principle of separation ? A.charge density B.molecular weight C.polarity of molecule I think it should be B.
0
votes
1answer
31 views

Ribosomes and DNA in chloroplast

Are there multiple copies of circular DNA and membrane bound ribosomes IN CHLOROPLAST ? Are polysomes found in them ?
2
votes
1answer
67 views

What will happen if we expose the brain to an intermittent light?

If a brain is exposed to an intermittent light are specific areas going to fire? If yes, which of them? Is there any experiment about this?

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