6
votes
4answers
218 views

If I built a concrete pool, would it ever contain fish?

Imagine that I built a concrete-walled pool the size of a football field and filled it with fresh water - obtained from another lake but free of bacteria, plantlife, eggs, etc. Would it ever, over ...
0
votes
1answer
54 views

Male behaviour during breeding season

The mountain blue bird build nests to attract females and exhibit aggression towards other males during breeding season. Which of the following is likely to give the birds maximal evolutionary ...
3
votes
1answer
75 views

Fear in elephants

It has been noted that elephants trained for war, as was done occasionally in earlier times, have still shown a tendency to panic in battle much more often when compared to a war horse trained for the ...
1
vote
1answer
56 views

Why are Lymphatic trunks part of the Cardiovascular system?

According to Wikipedia the Terminologia Anatomica (international anatomy standard) the lymphatic trunks are part of the cardiovascular system instead of the lymphoid system. Why did they make that ...
1
vote
1answer
92 views

Need of Creatinine Phosphate

In muscle cells most of the ATP's phosphate is with creatinine phosphate. So why is the displacement of the phosphate group done ? Is it because creatinine phosphate would give it's phosphate more ...
1
vote
1answer
158 views

Change of phase from juvenile to adult in plants

I tried googling this but couldn't get much information on this. Most of the articles were about induction of flowering. I am more interested in knowing what factors influence the conversion of ...
2
votes
2answers
316 views

What is an 'ex vivo' experiment?

Simple terminology question: Is there a hard boundary between in vitro and ex vivo? Is there a hard boundary between in vivo and ex vivo? Suppose a sensory neuron is electrically recorded in the ...
4
votes
3answers
94 views

What makes a metal safe to use for an artificial joint?

What determines if a metal is suitable for transplantation such as in the hip? What I am most interested in however is why might some metals be toxic to animals once in the body?
0
votes
5answers
263 views

Is evolution true as Darwin said? [closed]

I was telling the theory of evolution to my friends. But they asked me for the proof. They said, we are not seeing any such transition species at present. Neither we have such evidence for evolution. ...
2
votes
1answer
38 views

What are the methods for infering genetic interactions?

Is there a classification of methods for inferring genetic interactions? I mean some work published, utilizes genetical genomics data. Is this possible with expression data alone? And how about ...
3
votes
1answer
50 views

Effect of arteriole dilation on vein

If an arteriole leading to a capillary bed is dilated will the pressure in the vein coming out from the bed decrease ? Will the velocity of blood in the vein change ?
0
votes
0answers
24 views

Presence of lignin and pectin

Are lignin and pectin present in primary cell walls or only in secondary walls? The sources available on google are confusing?
0
votes
1answer
113 views

Organelles present in sieve tubes

I know that sieve tubes do not have ribosomes, nuclei and cytoskeletal elements. What other organelles does it not have? Does it have a cytoplasm?
1
vote
1answer
76 views

Rate of Evolution of population of long lived individuals

Is it necessary that rate of evolution of longer lived trees will be lesser than that of annuals ? I understand that new individuals will come up faster in annuals and it may adapt to varying ...
3
votes
0answers
30 views

Division of Polar Body

The first polar body formed after meiosis-I is completed in oocyte, may or may not divide. Why is the statement that "it may or may not divide"? Is it random ?
0
votes
1answer
148 views

Need of X or Y chromosome protein after meiosis

After meiosis each spermatid get either the X chromosome or the Y chromosome. I know that the 4 spermatids formed from 1 spermatogonia are connected by cytoplasm and so the proteins made by X or Y ...
2
votes
1answer
137 views

Do people of the same height walk at the same speed?

I'm working on a project that concerns movement and the human body. Before I begin to experiment, I need an answer to a question I'm sure has an answer, but doesn't Google well. What I need to know ...
5
votes
1answer
53 views

How do rodenticides with delayed effect work?

Most modern rodenticides are claimed to cause death no earlier than several days after ingestion. That's quite strange - once a chemical was ingested it will be absorbed in the digestive system and ...
8
votes
1answer
144 views

Is it a limitation of the eyes, or the brain, that we can't see a moving bullet?

Are the photoreceptors in our eyes not fast enough to register the fast moving bullet, or is the brain not powerful enough to make sense of something happening that fast?
4
votes
1answer
2k views

What's a non-allelic gene?

Non-allelic or non-alletic I stumbled across the term in my Human Genetics textbook. It didn't explain it there, and a quick google search only showed scientific papers that refer to 'recombinations ...
7
votes
1answer
394 views

RNA seq and using of Poly(A) or non-Poly(A) based amplification of RNA

I'm studying "Deep sequencing the circadian and diurnal transcriptome of Drosophila brain" Hughes et al., 2012. I've got some problems with the materials and methods. Before RNAseq, the authors ...
0
votes
1answer
42 views

What happens to potassium after an action potential?

If I understand right, after repolarization, much of the potassium is outside the membrane and much of the sodium / calcium is inside. How does it get back to the original concentrations (i.e. ...
1
vote
1answer
129 views

Is there a human form of estrus?

Now I just learn that estrus is a trait in all mammals except Humans. So does it occur significantly in Humans? Of course I'm aware of the cliched "horny", "aroused" etc., but is it a biological ...
4
votes
1answer
173 views

Which organisms have introns?

From Wikipedia: For example, introns are extremely common within the nuclear genome of higher vertebrates (e.g. humans and mice), where protein-coding genes almost always contain multiple introns, ...
2
votes
1answer
309 views

Glycolysis and Non-Glucose Sugars

In my biology book's section on disaccharide metabolism and glycolysis, it states that sugars other than glucose must be acted upon to enter glycolysis. Let's take sucrose as an example. Sucrose is ...
6
votes
1answer
91 views

Is there a website that shows population sizes?

I'm looking for a website that shows the population sizes of a species (doesn't matter which) as a function of time at a geographic coordinate. Is there a government website or other free database ...
3
votes
0answers
51 views

Deducing synaptic strength from electron micrographs?

There are several promising techniques for connectomics based on iterative sectioning and imaging of tissue with scanning electron microscopes (e.g. FIB-SEM and ATUM) By looking at such micrographs, ...
2
votes
1answer
27 views

Osmoregulatory Acclimatization in amphibians

If a frog is gradually exposed to increasing concentration of salts can they acclimatise or will they die of exosmosis ?
1
vote
1answer
102 views

Hydrophilicity and polarity [closed]

If any given molecule is polar, and is capable of hydrogen bonding, I can be sure that it's hydrophilic. However, are those two the only conditions that make a molecule hydrophilic?
4
votes
1answer
49 views

RNA-seq Data on domestic animal with different environment

I want to find the RNAseq data available on domestic animals in different environments. If microarray data is available, it would be more useful. If you know I would appreciate to inform me.
2
votes
1answer
349 views

Which is the tissue damaging agent in krokodil (street desomorphine)

I've just read about krokodil and saw some quite hideous pictures about what it does to the human body. I guess just desomorphine alone wouldn't have this effect. Which ingredient(s) causes the ...
2
votes
1answer
72 views

Aerobe or facultative anaerobe organism that metabolizes acetate?

I'm assuming bacteria, but will take any suggestions. Organism must survive primarily on the acetate (plus trace elements), but I can give/take electrons, if necessary. Not interested in strict ...
3
votes
1answer
54 views

What is the cause of the spots on this leaf?

On a hiking trip to the Alps I found trees whose leaves showed those spots you see on the picture. I am curious about what the cause is. Higher resolution pictures of front and back side.
3
votes
3answers
69 views

Would Bubling Oxygen Through “Dead Zones” Like A Fish-Tank Make Much Difference?

I am a dilettante when it comes to dead zones. I realize that they vary from fleeting algal blooms to continuous dead zones. For the continuous dead zones it would seem to me that adding a "bubbler" ...
2
votes
1answer
248 views

Why are urban birds still scared of humans?

I understand that animals are naturally scared of humans because we basically slaughtered every living thing we found in our way for millennia. How long does it take for them to genetically 'forget' ...
2
votes
1answer
51 views

Can a chicken's lard become liquid depending on its diet?

On Cooking.se, somebody asked a question about the fat in chicken stock sometimes being liquid and sometimes solid once the stock has cooled. The only answer until now suggests that the difference is ...
2
votes
1answer
105 views

What is the full name of E. G. Gray?

E. G. Gray is Neuro scientist who found and described first the two major morphologically defined synapse types (Gray Type I (asymmetric) and II (symmetric)) in his work E G Gray (Oct. 1959). ...
3
votes
2answers
3k views

Why Do Healing Wounds Feel Warmer To The Touch?

I fell over on my bicycle trying to avoid running over a rattlesnake, and ended up badly skinning my knee. It immediately began to bleed, but soon clotted. It has been 2 days now and it has formed a ...
3
votes
1answer
260 views

How do I measure bacterial growth in agar dishes (either by cell mass or by cell count)?

I am doing an experiment in which I am growing S. mutans in agar dishes, and I am not sure how I would measure the growth of the S. mutans. I am also not sure if I would do this by measuring cell mass ...
1
vote
1answer
96 views

Which is the correct statement on proteins?

I need help with one of the questions on my biochemistry assignment Choose the correct statement on proteins: a) proteins are folded by alpha-helix b) proteins can preserve their function even if ...
3
votes
1answer
52 views

Does a large effective population size result in faster decay of linkage disequilibrium (LD)?

I am thinking about an invasive species that was introduced into North America just a few (<20) generations ago. Using microsatellite genotypes (105 loci), I have identified almost no significant ...
1
vote
1answer
91 views

What are the effects of muscle and fat mass on survivability?

If we have humans A, B and C who are different: A is thin (skinny) without significant muscle or fat mass. B is muscular C is fat Which one of them has the best body for survival in accidents like ...
4
votes
0answers
32 views

Are there any online resources one can use to access raw clinical trial data without having to contact those involved in the study?

I want to do some statistical analysis and I have a preference for real data so I was wondering if there's somewhere I can get such data for free without a heap of bother in phoning other those ...
3
votes
2answers
286 views

Survivorship Curves: Type II curve mortality rate is not constant?

In graphs of survivorship curves, I'm seeing that the Type II curves are straight lines, and the supplementary text says that the mortality rate is constant (i.e. the slope of the line is constant). ...
2
votes
2answers
131 views

Hardy Weinberg Equilibrium after 5 Generations

1 There is a population not at HWE where red eye = $a^+$ (dominant) and white eyes = $a^-$. if $a^+/a^+ = 0.6$ $a^-/a^+ = 0.1$ $a^-/a^- = 0.3$ what are the frequencies of the $a^+$ and $a^-$ ...
3
votes
1answer
205 views

Possible Genotypes of 4 Alleles of Adh

There are four alleles of Adh which are Adh-1, Adh-2, Adh-3 and Adh-4. Their respective frequencies are 0.11, 0.84, 0.01 and 0.04. What are the Hardy-Weinberg frequencies of the possible 10 ...
0
votes
2answers
106 views

Gene Circuits; experiments

First, my background - I'm a newcomer to biology. What is a gene circuit, and how might I simulate one in a laboratory? Thank you.
3
votes
2answers
129 views

Are identical twins exactly the same?

http://www.scientificamerican.com/article.cfm?id=identical-twins-genes-are-not-identical According to this article some identical twins show differences with respect to their copy number variants. ...
1
vote
0answers
68 views

Harmful effects of radiation from cell phone towers? [closed]

As per this article - http://www.thehindu.com/news/national/mumbai-citizens-link-cancer-to-cell-phone-towers/article5139166.ece , people living adjacent to cell phone towers claim to have developed ...
4
votes
2answers
200 views

Melatonin production - requires nighttime, or just full darkness?

Is melatonin properly produced in daytime sleep in full darkness? Or does it require only nighttime sleep? Additionally, what other biological implications are there, if any, to daytime sleeping? ...

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