3
votes
0answers
45 views

Why is this dry pepper fruit still “powered”?

Check out this photo of my pepper plant this cloudy morning: (click for full res) Usually (and this can be seen on 2 and a half of the 4 fruits in this pic) the fruits are "disconnected" from the ...
1
vote
0answers
58 views

3' or 5' DNA capping protein

Does anyone know of a protein/molecule that can be attached to one end of the DNAs temporarily ? eg. i would like to only to allow one strand of DNA be ligated to another DNA molecule to either it's ...
1
vote
2answers
168 views

Do people often blow out the air from their lungs a lot when living in the cold condition to keep their lungs warm?

In a cold climate, do people often blow out the air from their lungs a lot when living in the cold condition to keep their lungs warm? I asked this question because it could connect to how people in ...
6
votes
2answers
93 views

How predictably will RNA polymerase not transcribe repetitive sequences?

I am working on an (expensive) synthetic construct, which happens to have many "repetitive" sequences within it that are integral to its function. Primarily, the two sequences that are worrying me ...
2
votes
0answers
44 views

What are these fleeting sea worms? [closed]

I filmed the creatures below this August in the Mediterranean (specifically, the port of Fornells in Minorca of the Balleares). The images were taken from a boat moored just outside the harbor and ...
5
votes
1answer
56 views

What limits our ability to grow enamel rods?

From what I've understood from what I've read (which might be wrong), enamel rods extend away from the dentin in our teeth. As young people grow, the rods are thickened. What are the technical ...
2
votes
0answers
32 views

How has the use and subsequent ban of DDT affected insect populations?

Living in Australia there were less ticks for example during the use of DDT, now there are more ticks prevalent here. I am wondering if any insect species have declined permanently as the result of ...
0
votes
1answer
1k views

For the human head, which direction is anterior, and which direction is ventral?

I read the wikipedia entry and I am sort of confused. In dog, the nose is toward the front. That's anterior. So I conclude that human nose is anterior. In dog, the head is on the back. So that's ...
0
votes
1answer
1k views

What is the difference between SNP and STR?

I thought that these were just different format of the same data. But it seems there isn't a way to convert SNP (single nucleotide polymorphism) data to STR (short tandem repeat) data. Am I right? ...
2
votes
1answer
62 views

Does the existence of one species imply the existence of many other?

Reading one of Sir Arthur Clarke's scifi stories, I came across a statement something to the effect of, existence of a single species automatically implies the existence of many other species. So ...
0
votes
1answer
86 views

Hypothetically, what is the smallest functional form of human?

Since the my first encounter with doraemon manga, I've been wondering many things, one of them is the small light. Assuming we had an instrument, such as small light, which enabled people to grow and ...
2
votes
1answer
95 views

Where does all the carbon go?

I found it hard to get numbers on global primary production, but apparently it's somewhere around 50-60 $Gt / year$ for carbon content in the terrestrial production, and a similar figure for the ...
14
votes
4answers
2k views

Why would a single celled organism evolve to be multi-celled?

I read a story this week on Richard Lenski who has been 'evolving' E. coli for more than 50,000 generations now. One comment I read was from someone who doesn't accept Evolution who pointed out that ...
1
vote
2answers
449 views

Why doesn't T5 exonuclease have endonuclease activity in Gibson assembly?

Gibson assembly uses T5 exonuclease to chew back the 5' end of dsDNA to generate overhangs. However, T5 exonuclease, in contrast to lambda exonuclease, is reported to have ssDNA endonuclease activity ...
1
vote
1answer
79 views

Identification of this plant?

Photographed in Rocky Point, Mexico. Any ideas about this plant? Thank you!
4
votes
1answer
192 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?
6
votes
0answers
111 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
292 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
110 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
234 views

DIfference between diversification and differentiation

In Adaptive dynamic : what is the difference between Ecological Differentiation and Ecological Divergence ?
3
votes
1answer
102 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
404 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
1k 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
272 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
80 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
89 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
263 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
338 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
30 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
388 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
357 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
40 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
681 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
80 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
585 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
89 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
106 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
79 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
76 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
142 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
196 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
37 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
378 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
16 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
389 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
1k 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
712 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
345 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?

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