All Questions

5
votes
1answer
83 views

Effects of selection on effective population size

Background The effective population size ($N_e$) is a central concept of evolutionary biology and is influenced by several parameters. For example: sex ratio bias affects $N_e$ $\left(N_e = ...
0
votes
0answers
16 views

Recovering Coma patient with theoretical full knowledge of heart function

In coma, there is the medullary depression (stage of agony). Spontaneous respiration and circulation cease i.e. vasomotor center. There is no full circulatory and respiratory support. Assume you ...
2
votes
0answers
44 views

When the mind is highly active, roughly how many neurons become excited in one second?

I'm curios to know how many times neurons send signals in one second when the brain is highly active (Highly active meaning during difficult problem solving, or any task that might bring the brain to ...
2
votes
1answer
59 views

What is the scientific and common name of this bug?

Captured this under my stereo microscope. Much beautiful than appearing on my camera sensor. Can someone help me identify it and explore more? Also is it having a compound eye ?
0
votes
1answer
17 views

Cell targets of Glybera

So we know that there is a first gene therapy drug in the market out there called Alipogene tiparvovec to address lipoprotein lipase deficiency (LPLD) at a genetic level. Does this genetic drug ...
1
vote
1answer
26 views

What is meant by a muscle fiber being glycerinated?

I was popped this questions today, "what is a glycerinated muscle fiber, and what is required for its contraction," and had little idea. I'm assuming the question is "what's required for its ...
0
votes
1answer
21 views

Do the light and dark reactions happen at the thylakoid?

My professor said that light reactions and dark reactions happen at the thylakoid. He did not choose the answer that "both reactions happen at chloroplast". Isn't the thylakoid a part of the ...
4
votes
1answer
30 views

What are “anchor regions” in the human genome?

I've been reading this paper entitled "A high-resolution map of the three-dimensional chromatin interactome in human cells", about interactome in 3D chromatin. We next applied the above algorithm ...
0
votes
0answers
28 views

Interpreting Graph

I am studying evolutionary biology, and been presented with this graph: I am having some difficulties understand its meaning. For a start, why is time measured as a fraction of the population size? ...
2
votes
1answer
31 views

The biology behind tree pruning and hedge trimming

I read two contradictory arguments which both seem logical to me, related to the tree pruning and hedge trimming: You should prune/cut trees only outside the growing season, when the tree is ...
0
votes
0answers
25 views

Do animals have social status as humans in our society?

As our society and it's functioning is closely related to the ones of animals, one question arises: Do animals in nature have social status as humans? People often display it publicly, by buying nice ...
1
vote
0answers
20 views

How many traits can a multivariate breeders equation handle?

The multivariate breeders equation (MBE) by Lande predicts the change in a trait $\Delta \bar z$ (response) as $\Delta \bar z = G \beta$ where $G$ is a genetic variance-covariance matrix and ...
2
votes
0answers
21 views

What do we know about the cellular structure, processes, environment, and immediate ancestors of the last universal common ancestor (LUCA)?

I am up for all scientifically sound speculations, and sources are highly welcome. I've looked into this quite a bit myself via scholar.google, the wiki article, and /r/askscience. I'm really looking ...
1
vote
0answers
29 views

What is this animal? A worm which make round hole in on the ground [closed]

From South East Asia. There are some (perfect) round small hole in my garden (d=0,3 cm). They are the home of a small, strange worm, which I can't know the name. When I put an bamboo young leaf (used ...
4
votes
0answers
38 views

What are the effects of long-term liquid breathing?

I just saw a recent Physics question that mentioned liquid breathing (which I had never heard of before) and I started to wonder about its long-term effects. Let's imagine a person underwent liquid ...
3
votes
0answers
55 views

Understanding the meaning of $s$ and $t$ in a population genetics equation

Sewall Wright in this article (1937) at the end of page 313 gives the equation: $$\Delta q = (s+tq)q(1-q) \space\space\space\space\space\space\space\space\space(1)$$ This equation is an ...
0
votes
1answer
77 views

Why would the stroma have a higher pH during photosynthesis?

Here is a question form my test. If you could measure the pH of the interior of thylakoids and the surrounding stroma during active photosynthesis what would be the relative pH of each? The ...
2
votes
1answer
53 views

Active & passive transport question

If an element, ion or molecule is found in a cell is it possible to tell which method of transport was used? for example if a hydrogen or sodium ion was found in the cell could you tell if it got ...
1
vote
1answer
94 views

Preservation of human tissue

At my med school we have human samples (body parts, organs, etc.) They are soaked in some sort of solution for long term storage. I'm quite sure that it's not formaldehyde as that would be really ...
0
votes
0answers
17 views

Formaldehyde turns plantar region of feet red?

I'm a freshman med student and I've noticed that on all the feet (and hands) of deceased people that I've worked with, the bottom of the feet always turns red and also the inside of the palm? Why is ...
3
votes
2answers
55 views

Proteins with alpha helices alone and beta sheets alone?

I would like to see some examples of proteins with PDB ID so that I can download and see them in VMD software. I need some proteins with alpha helix only and proteins with beta sheets alone.
0
votes
1answer
36 views

Organisms using thermal energy as their sole energy source

After seeing this question I remembered that in secondary school we watched a documentary stating something along the lines of "all organisms derive their energy directly or indirectly from the sun. ...
1
vote
0answers
30 views

Visualizing GFP in transgenic rice seeds?

I want to express GFP in rice as a method for differentiating transgenic from non transgenic rice seeds. I want to know if I can visualize them using a hand held UV lamp as the GFP I will be using has ...
0
votes
0answers
9 views

Which pathways Montelukast can alter in blood pH and water homeostasis?

I am thinking which pathways Montelukast can alter in blood pH homeostasis, since there is an indication that Montelukast can increase the perfusion of intra-abdominal organs. It alters those ...
3
votes
2answers
45 views

Can radiation equilevant to 1 CT (computer tomography) scan causes significant changes in human body?

I've read that CT scan causes radiation equivalent to few hundreds of ordinary X ray scan. It sound scary at the first look of it but I wonder is it the amount considered significant? Can dosage equal ...
4
votes
2answers
441 views

Are there any multicellular forms of life which exist without consuming other forms of life in some manner?

The title is the question. If additional specificity is needed I will add clarification here. Are there any multicellular forms of life which exist without requiring the consumption (destruction) of ...
3
votes
1answer
32 views

NADH inhibits gluconeogenesis?

I was told in a physiology lecture that alcohol inhibits gluconeogenesis because 'NADH produced from ethanol catabolism leads to product inhibition'. But is NADH not a reactant coenzyme of ...
3
votes
1answer
31 views

Can chitosan affect the absorption of unsaturated fatty acid?

I know chitosan will decrease the absorption of fat. However unsaturated fatty acid, such as DHA, is beneficial. Does chitosan effect the absorption of unsaturated fatty acid?
0
votes
1answer
11 views

Is there any merit to Dawn dish soap killing fleas on dogs?

My Fiona had a completely raw tail from biting. I saw severe skin scaling (dandruff) and checked her for fleas. She is old so her stomach hair is sparse. I was always taught to check belly and inside ...
2
votes
1answer
26 views

What is the advantage to neurons being asymmetrical?

Does having a central axon and dendrites result in any advantage compared to if the neuron was symmetrical?
6
votes
1answer
83 views

Identification of small fuzzy flying insect (pic)

These critters were flying around the neighborhood on an autumn evening in Seattle, WA, USA. Their most notable feature was the small amount fuzz on them. They were quite slow in their flight compared ...
5
votes
2answers
91 views

Simulating substitution rate of neutral mutations

I am trying to computationally simulate a population based on the Wright-Fisher model I would like to get to the classic result of the neutral theory of molecular evolution that the rate of neutral ...
9
votes
3answers
66 views

How can I label cryotubes in a way that eliminates the problem of legible hand-writing?

My lab stores biological material (tissue, cells, plasma, serum) in a -130 C, liquid nitrogen freezer. The cryotubes that we use to store a samples are labelled by hand which frequently creates ...
1
vote
2answers
34 views

Incomplete Dominance and Probability

I have a follow-up question about an in-lecture question (this is not a homework question). As you can see I have already answered the question and the question is closed to further submissions. ...
1
vote
0answers
20 views

How do we determine a disease's incubation period?

There was a suspected case of Ebola in France, which was later dismissed, since the suspect lastly came into contact with a potentially contaminated person more than 21 days before, which is the ...
4
votes
1answer
34 views

Mechanisms of extracellular stimulation of neurons

When stimulating a group of neurons with an electrode, let's say we put it in a region that contains axons, what is the mechanism by which the axons are stimulated? I've been told electrodes ...
2
votes
1answer
216 views

Neurons with thousands of connections: where are the extra connections coming from?

If every neuron has only one Axon but can can have thousands of (or let's say, even just ten) incoming Axon connections via its dendrites, where are the extra connections coming from? It seems to ...
0
votes
1answer
38 views

Simplest Biological Organism? [duplicate]

What is the simplest biological organism from which a DNA sample has been or could be obtained? Could the resulting DNA be processed and examined in such a way that the resulting information would ...
0
votes
1answer
8 views

What studies are there showing the effectiveness of any substance on canine hypertension?

Searching on http://www.ncbi.nlm.nih.gov I could only find the article titled as "Telmisartan Treatment of Refractory Proteinuria in a Dog".
2
votes
2answers
26 views

What is refractory proteinuria?

I've stumbled upon the article "Telmisartan Treatment of Refractory Proteinuria in a Dog."* What is refractory proteinuria? *Bugbee AC1, Coleman AE, Wang A, Woolcock AD, Brown SA. J Vet Intern Med. ...
4
votes
1answer
33 views

Can anyone identify this caterpillar?

Can anyone identify this caterpillar we found on a cauliflower? This was the only photo we could get of it. Thanks!
3
votes
1answer
39 views

How does electrolarynx work?

I have heard that this is an effective replacement for patients who have a dysfunctional larynx, partly due to cancer. I am curious to know the inner working of this device and why such a robotic ...
0
votes
0answers
14 views

Why does some skin hold perfume longer than others

I was wondering my girlfriend and I used the same perfume for a while and we sprayed the same place. And after a day her skin still smells nice while mine smells normall. Will different types of ...
1
vote
1answer
65 views

Evolution, What would the first plants have been like?

I am curious what the first plants are thought to have been like, what they may have evolved from, and how much earlier (or later) than animals they are thought to have moved to land, if they even ...
1
vote
1answer
40 views

Book-recommendation: Ethology

I am looking for a book that covers the following topics in ethology: Behaviour Sensory filtering, reponsive-ness, sign stimuli, learning and memory, instinct, habituation, conditioning, ...
2
votes
1answer
27 views

Will an 11W UVC lamp kill bacteria?

If I shone a UVC lamp (11W) on something (say for example a plastic phone case) for an hour, would that kill off a noticeable amount of bacteria? That is, if I were to go over the case with a cotton ...
6
votes
0answers
81 views

Calculating additive variance, heritability, and percent of variance explained by additive effects

I've set up some dummy data in R which makes 40 genetically related lines (in this case I'm simulating hemiclones - they share one haploid copy of there genome within a line, thus additive genetic ...
0
votes
0answers
44 views

How much information can a single neuron hold?

I'd like to know how much information (information that can be interpreted into thought by the brain) a single neuron can hold. I understand that memory allocation is a very complex and ...
1
vote
4answers
49 views

Are neural connections one-way?

I'm trying to think about how two neurons communicate, typically shown in pictures as an electric pulse traveling along a long, thin connective tissue. Is this depiction somewhat accurate, and if so, ...
2
votes
0answers
33 views

Does the Jungian notion of collective unconsciousness have any legitimacy in the light of modern neurobiology and epigenetics?

Carl Jung has long ago proposed a rather controversial notion of collective unconsciousness [1, 2, 3], a form of the unconscious (that part of the mind containing memories and impulses of which ...

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