8
votes
2answers
158 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
331 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
116 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
266 views

DIfference between diversification and differentiation

In Adaptive dynamic : what is the difference between Ecological Differentiation and Ecological Divergence ?
3
votes
1answer
114 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
464 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
2k 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
275 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
87 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
75 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
96 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
287 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
363 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
31 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
66 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 ?
2
votes
1answer
468 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
373 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
42 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
870 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 ...
2
votes
2answers
87 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
655 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
96 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 ...
4
votes
1answer
126 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
84 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 ...
6
votes
1answer
78 views

Reformulation of Hamilton'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
156 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
217 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
40 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
402 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
17 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
407 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 ...
5
votes
2answers
2k 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 ...
8
votes
2answers
840 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
407 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?
-4
votes
1answer
198 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
163 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
84 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
2answers
113 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
189 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 ?
9
votes
3answers
14k 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
1answer
400 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 ...
3
votes
1answer
252 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
63 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?
1
vote
1answer
81 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
43 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
94 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?
1
vote
1answer
31 views

Amphibian blood circulation

In an amphibian blood entering the right atrium shows higher levels of oxygenation than that in left atrium when : A.It is hyperactivated B.it is hibernating C.it is submerged D.it is in the ...
2
votes
2answers
145 views

Difference between Medical and Airport scanner radiation

What is the difference between radiation doses of a medical scanner and airport security scanner (X-Ray full body scan)? Is it the same kind of radiation? Does it pose any danger for people who fly ...
2
votes
3answers
72 views

Use of salt as preservative

I know that salt is used as preservative as it dehydrates microbes. Is there any other advantage like - altering pH or inactivating microbial enzymes ?
7
votes
1answer
4k views

Why is fructose not glucose the main energy source of sperm?

The seminal fluid contains fructose as the main energy source for the sperm and not glucose. Why is fructose and not glucose the primary energy source for these sperm, since glucose is the ...

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