4
votes
1answer
88 views

How do steroids travel in the bloodstream?

Cholesterol, which is hydrophobic, cannot simply travel in the bloodstream, and instead is enclosed in lipoprotein (LDL, HDL). Steroids, which are derived from cholesterol, are also hydrophobic ...
4
votes
1answer
35 views

Forward versus backward numerical simulations in population genetics

My question is closely related to this post. There are a number of existing platforms to perform numerical individual-based simulation in populations genetics. An almost exhaustive list of such ...
4
votes
0answers
54 views

Why do some medicines induce sleep? [on hold]

I have seen lot of people sleep or say that they are feeling sleepy after taking some medicines. Why? I mean, if a medicine acts on some cell of the body because that cell has got its receptors and ...
5
votes
0answers
29 views

What have the L-systems (Lindenmayer systems) been actually used for in biology?

Wikipedia: An L-system or Lindenmayer system is a parallel rewriting system and a type of formal grammar. L-systems were introduced and developed in 1968 by Aristid Lindenmayer, a Hungarian ...
-2
votes
0answers
23 views

How hot can coffee be for it to burn the tongue? [duplicate]

How hot can coffee get before the tongue will get burned? I want to know an accurate temperature. Specifically coffee. I felt that the other question didn't have a definitive answer.
4
votes
1answer
67 views

Identify bee in photo (found in Utah, USA)

A friend took this photo of a bee in his back yard in central Utah (© Jon Mott, CC-BY 3.0). I have no formal training in systematics or entomology, so to me everything looks like the bees' poster ...
1
vote
0answers
47 views

Where do the H+ ions come from in light reactions?

In the light-dependent reactions of photosynthesis, H+ ions pass to the thylakoid space. Where do these protons come from?
1
vote
0answers
14 views

Calculating the canopy size (crown) of a newly planted tree at a future date

Assuming that one knows the maximum area of the canopy and the age of the tree when it achieves this. And given an initial canopy size from the nursery. How would I calculate the canopy size at a ...
39
votes
1answer
3k views

What could cause a forest of bent trees?

While hiking on the northern Idaho-Montana border, I encountered a large area where virtually every tree is bent at the base in the downhill direction. Only the very largest and very smallest trees ...
3
votes
2answers
249 views

What does this equation about DNA replication mean?

Could someone help me understand this equation please? I found it in a paper which said that it was DNA replication, but why? $\ce{dNTP + dNMP_{n} -> dNMP_{n +1} + PPi}$ I found that dNTP means ...
5
votes
1answer
46 views

Does the anatomy of our hand result in (computer) mouse-accuracy that varies by direction of movement?

First off, I apologize if this isn't the right stackexchange sub-site for asking thsi question. I was torn as to where I should post this question: it could plausibly belong in Biology, User ...
2
votes
1answer
54 views

Can you recharge without sleeping? [on hold]

Sometimes it's difficult falling asleep for almost an entire night. You might feel like getting up and being productive instead, or 'pull an all-nighter'. Or you can try to simply lay in bed to relax ...
2
votes
1answer
58 views

Has anyone modelled calcium oscillations using Matlab software? [on hold]

I have been trying to model calcium oscillations using MatLab, but I cannot obtain the oscillation. I created a function where I put all the equations and used ode15s to call the function. I have ...
3
votes
1answer
36 views

How does tearing work?

I found the question about tear gas very interesting. Shigeta says there that crying helps the cells of the eye to wash themselves clear of the toxic components in the tear gas. Does non-emotional ...
4
votes
1answer
24 views

Crow branch pecking behaviour

I was walking through a small park when two crows started cawing at me, and followed me, flying from tree-to-tree as I walked. I speculate that this is a territorial or protective behaviour, but what ...
4
votes
1answer
24 views

Phosphorylation-Dephosphorylation : ATP-driven VS spontaneous

Is protein dephosphorylation most commonly spontaneous (without need of ATP)? I came across some papers that mention it, as well as the opposite case (ATP-driven), but I can't figure out which is ...
2
votes
0answers
21 views

What are all of the currently known variations of the G zipper motif?

The G zipper motif is found in transmembrane proteins at an above random frequency and there are models explaining how it might help with multiple transmembrane intra-membrane helix bundle assembly. ...
1
vote
2answers
69 views

Why do many DNA solutions contain additional compounds?

DNA solubility data in only water is scarce. A previous question asked for a quantification of DNA solubility in water. It seemed like it would be easily answerable, however isn't quite that simple ...
3
votes
1answer
19 views

Accuracy of best plant growth models?

Given a plant $P$, predict its height $H$ at time $t$ since planting given some environmental variables $E_1, \dots, E_n$. How accurate are the state-of-the-art models for such thing? What data is ...
7
votes
1answer
375 views

Toronto spider identification

I found it in Toronto, Ontario, during early June, 2015. When prodded it seemed to jump around, or at least to move very fast. I can also post a short video of it if needed.
2
votes
1answer
40 views

Animal identification (larva)

I found a tiny, white animal in my mouth on the morning of June 28, 2015, in Toronto, Ontario. Luckily I don't seem to have hurt it. I was eating some sunflower and pumpkin seeds at the time. I ...
0
votes
0answers
32 views

How to resist the decreasing of your immunesystem after a cold shower? [on hold]

I have taken a couple of cold showers because I heard of the positive effects. I kindof like to take a cold shower now but I get the cold after I take them. After my first 5 cold showers or something ...
7
votes
0answers
25 views

Can a lizard shed a regrown tail again?

Some lizards are famous for their ability to voluntarily shed their tail to elude predators (Autotomy). After a while, the tail will be regenerated, though with slightly different qualities, as ...
4
votes
1answer
46 views

Parents are Rh +ve and child Rh -ve

Suppose the two parents of a child have blood groups A+ve and O+ve, and the child has O-ve type. For blood group, there are two alleles. Since the child has O, the father must have one 'A' allele and ...
-3
votes
0answers
15 views

Why does the growth of hair are faster than the growth of other cells in humans? [on hold]

We might have observed that growth of hair is more than growth of any other cells in human body ? Why is it so ?
0
votes
0answers
17 views

Why 'blood vessels' and not 'blood tubes'? [migrated]

I have a silly question. The way I imagine arteries and veins are as tubes that arise from one part and carry blood to the other part. Why do we call them 'vessels' (which reminds us of cooking ...
5
votes
1answer
33 views

Evolution of diversity and extinction resistance

I saw a comment on an answer to another question that touched on an interesting topic: keeping diversity is useful for parameter exploration or to adapt to future environmental change My initial ...
5
votes
2answers
149 views

Are we more attracted to people of the same ethnicity? [on hold]

Are humans more attracted to people from their own ethnic groups? I ask this because most of the time people have relationships with people of their own ethnicity, and I wonder if it's purely social, ...
3
votes
1answer
68 views

What is this small black bug found in Turkey?

What species is this? It was found in Turkey. It was dead, I did not kill it.
1
vote
2answers
22 views

Autotrophic and heterotrophic organisms in anaerobic condition

Can both heterotrophic and autotrophic organism survive in anaerobic conditions? If an autotrophic organism does not produce carbon dioxide but requires oxygen, it should not be present in anaerobic ...
2
votes
1answer
31 views

Database of medically validated SNPs

I'm looking for all possible sources of clinically tested human SNPs. There is a handful of databases that store SNPs (like dbSNP), but I only need those that have validated presence/absence of ...
17
votes
3answers
999 views

Why does the face turn pale in dangerous situations?

I know what the effects are of a dangerous situation on the brain, i.e., an activation of the hypothalamic-pituitary-adrenal (HPA) axis which eventually results in an increased heart rate and elevated ...
0
votes
1answer
19 views

Which pair of primers should be used to amplify the ORF in PCR? [on hold]

So I want to choose the correct set of pair of primers to amplify the ORF of the gene that corresponds to amino acids in a protein. The start and stop codons are underlined. (I know that these need to ...
1
vote
0answers
25 views

How to be a Noah-esque biopirate and store the genes of every plant and animal [closed]

Preamble. Please criticize this idea. It is too romantic to be possible. All of the news about the sixth extinction got me thinking about it. Thanks The price of DNA sequencing for humans has ...
-1
votes
0answers
29 views

What did the transition from ovipary to Hemotrophic viviparity look like? [closed]

Most evolutionary changes happened slowly over countless generations. Richard Dawkins illustrates this beautifully in Greatest Show on Earth when he describes lining a rabbit up next to all her ...
2
votes
1answer
24 views

If a trait does not appear to be advantageous to organism, why does the organism have it? [duplicate]

Why do organisms have some traits that do not appear to have any evolutionary advantage?
3
votes
0answers
23 views

What is the meaning of conservation site in miRNA-mRNA pairing context?

I am not biologist and just work in Bioinformatics field. Does anyone know what is the meaning of conservation in the context of miRNAs and their pairings to mRNAs? Example: Each of these duplexes ...
0
votes
0answers
24 views

IC50 and area under the curve

I was hoping to get some clarification on how drug response data (i.e. IC50) are presented. On publicly available datasets like Genomics of Drug Sensitivity in Cancer, area under the curve (AUC) ...
4
votes
2answers
53 views

Exhalation while holding breath

If you inhale to your maximum capacity and hold your breath for an extended period of time, it begins to feel uncomfortable; slowly releasing your breath at this point seems to provide relief from ...
0
votes
0answers
25 views

Why do human have continuously-growing hair on their head? [duplicate]

Why do hair continuously grow on human heads, while the same doesn't happen on other parts of the human body? Where there are hair, they only usually grow to a fixed length; but they seem to have no ...
2
votes
1answer
43 views

What causes head hair to be different than body and face hair?

If you feel your head hair, it typically feels a lot softer and is easier to manage (comb, brush, fix) than a lot of other hair on your body - specifically I'm thinking about beard hair and pubic ...
2
votes
1answer
27 views

Which process is right to describe V(D)J recombination? RAG-1 and RSS recurring process

I'm studying V(D)J recombination. I think I have two incompatible books about explantaion of the process. Which is right? In Molecular Biology of the Cell 5th Ed., firstly RAG (-1?) combines to RSSs ...
4
votes
3answers
948 views

Why is wind cold for humans? [closed]

Coming out of the pool the other day, I felt very cold because I was wet and the wind picked up. My idea is that a "cold" feeling should be associated with low temperatures, but it's indeed wrong. ...
-1
votes
1answer
17 views

is left brachiochephalic vein and left pulmonary artery is same?

I am reading about ligamentum arteriosum which connects the left pulmonary artery and descending aorta. But I am seeing that if any figure shows left brachiochephalic vein it does not show left ...
-4
votes
0answers
19 views

Southern blotting [closed]

i am a student at the University of Reading studying Biological Sciences and one of my modules is called Practical Recombinant Genes exercise. We were given some questions to answer for our exam ...
3
votes
2answers
32 views

Deciding a reasonable threshold for copy number variation in a CNV (SNP array) TCGA dataset

Is there a methodology to select a reasonable threshold for copy number variation in a CNV (SNP array) TCGA dataset, to define when there is a significative alteration? Can I download CNV data for ...
-1
votes
0answers
18 views

Is spore print counted as organic material? [closed]

A friend of mine is travelling in the Netherlands and he came by a shop which sells spore prints. As far as I know, in my country it's illegal to get organic materials from other countries. I wanted ...
17
votes
6answers
3k views

If a trait would be advantageous to an organism, why hasn't it evolved?

If a trait would be advantageous to an organism then why hasn't it evolved yet? Conversely, if a trait is not advantageous or mildly disadvantageous, why does it exist? In other words why does ...
3
votes
0answers
14 views

Why is the administration of exogenous Anti-D not harmful to the foetus?

Haemolytic disease of the newborn can result from Rhesus incompatibility in utero. In this disease a Rh-ve mother becomes exposed to the antigens of a Rh+ve foetus by fetomaternal haemorrhage causing ...

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