2
votes
1answer
89 views

Is Hypericum Perforatum (St. John's wort) a C3 or C4 plant?

I've been curious as to which photosynthetic cycle St. John's wort uses to synthesise glucose and more complex carbohydrates. I know it probably won't be the crassulacean acid metabolism (CAM) cycle ...
1
vote
1answer
74 views

Recombination-based vs. Sequence-based genetic mapping

Now that sequencing is becoming increasingly cheap, what is the value of recombination-based genetic mapping against the sequence-based genetic mapping? I think that in the past recombination-based ...
4
votes
2answers
179 views

Current state of direct RNA sequencing

I had a colleague ask me recently whether mRNAs could be sequenced directly. I found this Nature paper[1] published by Helicos in 2009, in which they describe their developments in the area. It's been ...
0
votes
0answers
139 views

Growth kinetics of E.coli on media containing lactose and casein

I did this experiment last month using E.coli isolated from raw milk and have following data via uv-spec: ...
4
votes
1answer
2k views

Why do sneezes come in pairs or more?

I very rarely sneeze just once, usually there's two coming in a row, and I've noticed the same thing in other people and even in animals. Is there any reason for this?
2
votes
0answers
69 views

What determines the (perceived) frequency of tinnitus?

I noticed that every time I suffer temporary tinnitus after going to a very loud concert, the frequency I perceive is identical. I'd put it somewhere around 17KHz, but it's difficult to pin down with ...
5
votes
1answer
201 views

Are descriptive statistics sometimes more useful than tests of significance?

How does the biology community currently feel with regards to publishing descriptive and effect size statistics rather than significance stats? Almost every journal article I read in the cell biology ...
1
vote
2answers
563 views

Batch convert miRNA names to Accession IDs?

Does anyone know of tools to convert lists of miR names to their miRBase Accession IDs? I know they exist, but my search keeps pulling up gene ID converters. EDIT: both @rg255 and @shigeta have ...
0
votes
2answers
70 views

What is a “tool strain”?

When a biologist is talking about a genetically engineered mouse strain which is a "tool strain", what does that mean? What is the exact definition of a tool strain? What is the difference between a ...
0
votes
1answer
1k views

How many nucleotide pairs code one gene?

As I know three nucleotide pairs (triplus) code one gene. But I have found next information in the "Molecular biology of the cell" by Bruce Alberts: Mycoplasma genitalium: it has only about 480 ...
7
votes
3answers
843 views

What is the difference between a circular and a cat's-eye pupil?

I've been to local zoo the other day and one lizard caught my attention: its pupils are circular, which, I thought, is not usual for reptiles. Turns out it is, but now I can't find any explanation on ...
2
votes
1answer
2k views

Speciation by polyploidy

Speciation can occur by polyploidy. My understanding of the process is as follows: 'polyploidy is when the number of chromosomes in an organism's cell doubles. This means that the organism has more ...
1
vote
1answer
129 views

Chemical structure prediction

I'd like to do chemical structure prediction using a known molecule formulas. I'm familiar with de novo protein structure prediction, but are there any programs which will go from formula to structure ...
3
votes
0answers
36 views

Can a sound frequency 'not' within human hearing (20 Hz - 20 kHz) damage hearing when it is of high volume? [duplicate]

We can't hear sounds outside the range of 20 Hz - 20 kHz. However, if an inaudible sound is played at high volume, will one's hearing be affected?
1
vote
1answer
1k views

What is the appropriate blender speed to maximize nutrition and digestion of fruits and vegetables?

Blender companies state that a blender for smoothies should have speeds of at least 30000 rpm. They argue that only at 30000 rpm are cells of fruits and vegetables sheared enough to maximize nutrition ...
2
votes
2answers
333 views

What exothermic reaction distinguishes warm blooded animals?

I would appreciate an answer specifically in the form of an exothermic chemical reaction. Namely, the one primarily responsible for generating heat in warm blooded animals that does not take place in ...
1
vote
1answer
80 views

Can IVF decrease the probability of trisomy in the fetuses of older mothers?

Is trisomy mostly due to complications with fertilization? If so, does in vitro fertilization reduce the probability of trisomy for the fetuses of older mothers? If not, can zygotes be screened ...
4
votes
2answers
90 views

Combining gene expression data from two species

I currently have two sets of gene expression data. The first is a dataframe of genes identified by Annotation id CG numbers (for example "CG10005") in one column and a numerical variable of interest ...
1
vote
1answer
83 views

What in soy are people allergic to and will these allergens be passed along if an animal that has eaten soy is consumed?

I have two related questions about soy allergies and possible reactions. What is it that are humans who have soy allergies actually allergic to? What is the allergen? If an animal eats soy, are ...
3
votes
2answers
43 views

Have novel interactions or pathways been predicted by GRN or PPI data and later confirmed by experiment?

I've been learning about the gene regulatory network (GRN) and protein-protein interaction network (PPI) recently. I've found a huge amount of extremely interesting papers about how biological network ...
0
votes
1answer
38 views

Does the Enzyme Monoamine Oxidase, Isoenzyme A have an allosteric modulatory site?

Does the Enzyme Monoamine Oxidase, Isoenzyme A (MAO-A) have an allosteric modulatory site? I ask because I would like to know if it is possible, in theory at least, for a positive allosteric modulator ...
3
votes
1answer
98 views

Antibody-antigen database

Is there a database where I can find an affinity estimate if I provide a given antibody and a given antigen sequence ? Input : antibody + antigen sequence Output : quantitative binding/affinity ...
8
votes
1answer
666 views

How is instinctual information encoded?

If instincts are passed on through genetics, how is that information encoded in DNA? For example, spiders instinctively know how to spin webs. Does that imply that the algorithm for web spinning is ...
1
vote
0answers
31 views

Are anti-inflammatories useful for tendinosis?

I am wondering why some doctors prescribe anti-inflammatory treatments for conditions that are supposedly not inflammatory such as tendinosis. From my understanding, only tendinitis a swollen tendon ...
13
votes
3answers
278 views

Can plants get cancer?

I can't think of any reason why plants wouldn't be able to get cancer, but I've never heard of a plant growing a tumor. I've also never seen a plant with a noticeable abnormal growth. Can plants get ...
1
vote
1answer
441 views

Number of reading frames in nucleotide sequence

In class of molecular biology was posed this question: "How many reading frames start in sequence of nucleotides 5' ... ATATGAATGATGACAT... 3' ?"
0
votes
2answers
99 views

Is there any evolutionary/physiological advantage to multi-lateral symmetry?

Just wondering ; I get the impression a large number of multicellular organisms are multi-lateral in their physical structure. Why would evolution/mutation have retained multi-lateral symmetry in an ...
4
votes
0answers
84 views

What controls leaf senescence in deciduous tree species, and how can I predict it?

If I want to predict litterfall, what data do I need to collect, and what statistical model might I use? For example, I might use the following coding to record phenological stage every other day, or ...
8
votes
2answers
6k views

Agarose vs agar? Why do DNA gels use agarose only and how do you obtain agarose from agar?

Agar is a relatively cheap substance from red algae. And it contains a saccharide agarose as well as a small amount of pectin. Agar is used for culture plates as is, but for DNA gels a grade of ...
2
votes
1answer
862 views

Perception of artificial light - flickering

I noticed something strange a couple of years ago. I was walking down the street at night, when it struck me that the street lights were flickering. But, when I turned to take a direct look at the ...
2
votes
1answer
2k views

How does a thymidine block halt DNA synthesis?

The best I've been able to find is that there's a feedback mechanism, but what is this feedback, and how does the mechanism work? If it's just that the concentration of thymidine is too high, why ...
1
vote
1answer
53 views

Are there any neurotransmitters that trigger all neurons?

I'm reading into the basics of the nervous system, and am intrigued by neurotransmitters. I understand that certain neurotransmitters can trigger more than one neuron type, and may be used as ...
5
votes
2answers
107 views

Is there a strong reason to be sceptical about the “cured HIV patient” being reported by mainstream media?

There's a story going round the news about a baby that was, apparently, cured of HIV using a cocktail of drugs at an early age. The story piqued my interest, but details seem scarce. One of the main ...
7
votes
1answer
53k views

What causes random long white body hairs?

I'm sure many of you have experienced this - you scratch your back or brush your hand over your arm and find a ridiculously long thin white hair, sometimes as long as 3 or 4 inches. I know a few ...
2
votes
2answers
159 views

What chemicals can be detected from one's sweat?

This question came to mind after reading this article. The article speaks of inducing sweating to determine by a roundabout fashion the amount of salt therein. I'm no medic but I find myself wondering ...
0
votes
1answer
341 views

Does one neurotransmitter travel all the way through the nervous system?

Nerve impulses of course go really fast, but the neurotransmitters have to travel through millions of nerves, so how can it go that fast? Is it a sort of relay with lots of neurotransmitters taking ...
1
vote
1answer
1k views

Serotonin - Does being aroused make you sleepy?

My Psychology text book says Serotonin causes "Sleep, arousal levels and emotion" Does this really mean that when you are being aroused, Serotonin is released, which in turn makes you sleepy? If so, ...
1
vote
2answers
67 views

Is it possible to do chip-seq on a specfic region?

Is it possible to do Chip-Seq on specific region of the genome. The idea is to enrich before the sequencing step to have more sensitivity.
4
votes
2answers
2k views

How can I resuspend a cell pellet without harming the bacteria?

When using a preculture with Ampicillin in my protein expression, I have to get rid of the preculture medium to avoid carrying over too much beta-lactamases that will destroy the ampicillin in the ...
2
votes
1answer
67 views

Formation of ammonia from air and moisture

On extended bicycle trips I sometimes slept under a plastic sheet, which helped with mosquitoes on hot nights. But there was a noticeable build-up of ammonia which made this almost impossible for more ...
6
votes
1answer
535 views

Exercise causes number of cell divisions to approach Hayflick limit faster? And hence shorten life expectancy?

A world class athlete spends a lot of time performing intense exercises. Correct me if I'm wrong, but I assume that these intense exercises causes significant damage to the athlete's cells, but with ...
1
vote
2answers
310 views

By what mechanism does penicillin resistance usually develop in Streptococcus pneumoniae?

There are three mechanisms: prevention of the interaction between antibiotic and the target PBP; modification of the binding of the antibiotic to the PBP; hydrolysis of the antibiotic by a ...
3
votes
1answer
39 views

What Makes A Pet Hypoallergenic

I know you can purchase dog and cat breeds that are hypoallergenic so those who are prone to pet allergies will have reduced allergies or none at all. These breeds are specifically bred for that ...
7
votes
1answer
119 views

What causes XYY Syndrome?

It's obvious how a misdisjunction can result in klinefelter's syndrome (XXY) but I don't see how this can result in XYY syndrome. Your parents have a collective total of only one Y chromosome so how ...
1
vote
1answer
62 views

Do repeated freeze-thaw strip nutrition from vegetables/food?

For some inexplicable reason from the ladies in my extended family (even friends!) seem to believe that vegetables/food should be subjected to as few freeze/thaw cycles as possible. The rationale put ...
2
votes
1answer
231 views

How does this diagram illustrate carbon cycling in lakes?

Could someone please explain the following process to me: This process refers to carbon cycling in lakes and is described in the context of $CO_2$ flux from lakes into the atmosphere. GPP is gross ...
2
votes
0answers
152 views

How much food can an average person eat, and which animal is that equivalent to?

When the average person overeats, how much food can he eat in a day? Which animal's average meal would that be equivalent to? When documentaries are talking about animals feed, they usually say ...
0
votes
1answer
232 views

A good textbook on Neuroscience [closed]

I want to start learning Neuroscience. Can someone give me an advice about a nice textbook for beginners? I'm particularly interested in the application of Neuroscience in programming and AI ...
8
votes
2answers
2k views

What makes a gene dominant or recessive

We all carry two copies of each gene (outside of male sex chromosomes). If the two differ from each other often one is dominant and one recessive. How does this mechanism work on a molecular level? ...
1
vote
2answers
119 views

Plants without bacteria? is it theoretically possible?

I know from school, that all live on the Earth need bacteria as low-level "machines" that break down/extract/convert/produce chemical elements and combinations, other high-level organisms needed. But ...

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