All Questions

15
votes
0answers
186 views

Effect of Aging on SA node's sympathetic fibers

I am trying to understand the effect of aging on the sympathetic fibers of SA node. I know that aging shifts the vagal curve to left in frequency due to aging. However, I am interested if aging has ...
13
votes
0answers
279 views

What are these bladder snail parasites?

I collected some bladder snails several months ago. While checking them out one day, I noticed that they were now infested with external, parasitic worms. Here's a picture of a snail with a bunch of ...
13
votes
0answers
1k views

Contact Inhibition of Cell Division: Signaling Pathway

The following article refers to contact inhibition of cell division in epithelial cells, specifically MDCK cells: Collective and single cell behavior in epithelial contact inhibition. In their review ...
11
votes
0answers
242 views

Identifying Some Kind Of Fossil

This was found off the coast of Ireland by a friend of mine. The running gag is it's some kind of fetish or totem and should be immediately discarded, but we're interested in whether it's perhaps a ...
10
votes
0answers
261 views

What is this thing that is growing in my yard? And should I get rid ot if?

I live in Wilmington, Delaware (Mid-Atlantic USA). The north side of my yard is largely shaded by my house and grass is spotty. Periodically when I go into the yard I will find as many as four pod-...
10
votes
0answers
261 views

Which is the reference 16S rRNA

Recently, I've stumbled upon a fact, which hasn't bothered me for many years. The fact is that all universal 16S primers are written as "[FR][0-9]+" (in regex notation), that is they have a position ...
9
votes
0answers
38 views

Why are market squid attracted to fishing lights but also avoid naturally lit surface waters during daytime/full moons?

Squid fishermen use really bright lights (which can be seen from space!) to attract squid to the surface at night, but a lot of squid also naturally avoid surface waters that are lit during the day (...
9
votes
0answers
113 views

I am trying to identify this plant

I am trying to identify this medium arching shrub growing to about 1.5m high x 2m wide in the subtropical climate of the Mt Coot-tha Botanic Gardens in Brisbane, Australia. Unfortunately there was no ...
9
votes
0answers
144 views

What predates on cactus in the Atacama desert?

Introduction Last week, I was in the Atacama desert where I've seen many cacti. Some / many of them were seemingly suffering from predation. Most of predation seemed to be on cardón, often restricted ...
9
votes
0answers
253 views

Anatomical Angle Made by the Fingers of an Extended Palm

Does the angle made by the fingers (excluding the thumb) of an extended palm (as shown in the figure below) have a name (such as the Lovibond or Cobb angle, for instance) ? I have already checked ...
9
votes
0answers
740 views

Did I just watch a spider die?

So I'm sitting in my office and all of a sudden a small spider is gliding down on a web string from the ceiling, right in front of my eyes, and down onto my desk. It proceeds to make a few awkward ...
8
votes
0answers
228 views

Help identify this creature

I found this strange insect while on Son Tra, Da Nang in central Vietnam. It was about 4cm long and although it was on the ground, was obviously capable of flying. I've never seen anything like this ...
8
votes
0answers
215 views

What is the half-life of dNTPs at 95⁰C?

I'm looking for the half-life of dNTPs, either as a whole or broken into individual bases, at 95 degrees C (or similar). A titration would be great if that exists. I can provide more specifics if need ...
8
votes
0answers
191 views

How does a garlic clove thrive inside a closed refrigerator?

A garlic clove has been growing very well inside a closed refrigerator. It has developed beautiful green stalks, which I think are the equivalent of leafs. Since they are green, I assume they ...
7
votes
0answers
97 views

What is this underwater creature?

West Bali, about 10 meters deep. Body is roughly 10 cm across. Does not move.
7
votes
0answers
98 views

Do ring species exist?

In trying to understand evolution better, I have been looking at examples of speciation, and have thus come across the topic of ring species. I have tried to find concrete examples of how these work, ...
7
votes
0answers
78 views

Cold water sour taste

Recently I underwent a wisdom tooth extraction, and while there is still numbness I have observed something peculiar. If I drink cold water, it tastes sour, however the same effect is not observed ...
7
votes
0answers
85 views

Could these be Mycetozoa?

I found this on a forest in Mexico City. It was kind of a warm day (around 15°C). It had been raining a few days prior and it was quite humid, but not suffocating. This orange thing was on top of a ...
7
votes
0answers
2k views

Does a queen wasp sting also have poison?

Last night I got sting by a wasp and because of the time of the year I suppose it is a queen. But usually it swells and hurts for a day after it, but this time nothing happened only that I woke up of ...
7
votes
0answers
824 views

Is there a karyotype database for human cell lines?

I'm looking for the karyotype of a specific cell line. Some karyotypes are well known, such as HeLa or some carcinomas, but some are very hard to find, such as LG2 (B cells). Is there a database ...
7
votes
0answers
626 views

Genetic expression in interspecific hybrids

Referring to interspecific hybrids, I have the following two questions:- Quoting from wikipedia:- The offspring of an interspecific cross are very often sterile; thus, hybrid sterility prevents ...
6
votes
0answers
76 views

Where does Darwin state his “principle of multiple utility”?

I have never heard of Darwin's 'principle of multiple utility', but several papers refer to it. For example, from Darwin at the molecular scale: selection and variance in electron tunnelling proteins ...
6
votes
0answers
41 views

Does cheese contain cells of animal stomachs?

When cheese is made with calf rennet, is it possible that the cheese contains cells of this calf (stomach)? Dried and cleaned stomachs of young calves are sliced into small pieces and then put into ...
6
votes
0answers
105 views

Found in blood sample - what is it? Hopefully not a nemotode-

After examining someone's blood - through microscope - I found these. There were some more that were not photographed. Could someone please inform me on what these are? Maybe abiotic material on the ...
6
votes
0answers
125 views

What spider is that in south of Brazil?

I'd like to know if it is possible to identify the spider in the photo below. In fact, as shown in the next picture, it is very small. Location: South of Brazil.
6
votes
0answers
130 views

What is the name of this plant or shrub?

I just found a plant in India. Here is its leaf. I tried looking it up on flowers of India & wikipedia, but both databases are too much to read manually. Physical description: Each Stem has 6 ...
6
votes
0answers
399 views

What is this strange worm-like creature?

Hi! While I was in my front yard this morning, I happened to look down and see this little guy wiggling thru the grass. He isn't like anything I've seen before. He is about 2 1/2 inches long. He has ...
6
votes
0answers
72 views

Any references contradicting Hormesis from low dose studies?

I've recently read some papers on Hormesis (the stimulatory effect of low doses of substances toxic at high doses). The papers are all published in respected peer-reviewed journals, here, here, and ...
6
votes
0answers
47 views

Relation between bases while changing into a SNP

Is there any relation or influence among the bases (A, C, G, T) while they are converted into a snp? Such as, is A converted ...
6
votes
0answers
673 views

Squirrel nest construction

I've often wondered how squirrels -- specifically, eastern grey squirrels (Sciurus carolinensis) make their nests. Specifically, I've been curious about how they "weave" everything together to make ...
6
votes
0answers
218 views

How to estimate heritability from breeding data

I have a lot of plant-breeding data (tens of thousands of results) that are composed of phenotypes of parents and offspring. The plants however went trough years of selection and it is not balanced. ...
6
votes
0answers
8k views

What's the technical difference between fainting (and being unconscious) and falling asleep (and sleeping)?

This is actually a popular question along google results but the answers usually sound like: sleep is voluntary (oh is it?) and healthy fainting is result of accident and is not normal I read those ...
6
votes
0answers
141 views

Identity by descent among unrelated individuals

I was reading a couple of papers which talk about IBD (Identity by descent) among unrelated individuals (for eg. http://www.pnas.org/content/109/4/1193.long). However they do not seem to clearly ...
6
votes
0answers
173 views

Comparative cost of RNA-seq vs sequencing full length cDNAs

I am in the process of assembling and annotating the genome of a non-model organism, using almost exclusively short read (paired-end Illumina) data. Throughput is one obvious benefit of these data (...
6
votes
0answers
111 views

What metabolically happens when an egg fuses with the nucleus of a somatic cell

In stem cell biology, it is recognized that embryonic stem cells are transcriptionally inactive for the first 3 days of development. However, during somatic cell nuclear transfer, the nucleus is ...
5
votes
0answers
38 views

Is there a macroscopic amoeba-like organism that lives on land?

In the early 1970s, as a teen, I hiked in Rocky Mountain National Park, going up the base of a mountain. The path went through a deciduous forest (there were brown leaves beneath the trees) and I saw ...
5
votes
0answers
42 views

What is the thickness of the biosphere?

In other words, what is the vertical distance between the deepest and highest point on Earth where life is found? Life has been discovered at the bottom of the Mariana Trench, 13 km below sea level. ...
5
votes
0answers
27 views

What anatomical structures do baleen whales use to vocalize?

What anatomical structures do baleen whales use to vocalize? How does this differ between species?
5
votes
0answers
36 views

What kind of mite is this?

I found this (mite?) on my head skin close to hair. Is it a common dust mite or something else? Photographs under a simple microscope (10x objective) are below. Size is in the order of tenths of mm. ...
5
votes
0answers
51 views

Realistic Application of CRISPR in Human Disorders

Human trials recently began to use the genome editing technology CRISPR to treat sickle cell anemia using edited stem cells. Sickle cell anemia is caused by a single DNA Mutation, and is also a ...
5
votes
0answers
36 views

Firefly mating displays

I live in the northeast US, and really enjoy firefly displays at dusk in the summer. However, when paying attention this summer, I noticed that the fireflies were not displaying every night, but ...
5
votes
0answers
135 views

Could being exposed to excess UV in the arctic lead to a human eye color change? If so, what is the mechanism?

The CBS News article Expedition Antarctica: A father and son's journey to save the planet says (in part): Thirty-two years ago, Robert Swan made history as the first person to walk to both poles. ...
5
votes
0answers
223 views

Can any animal ejaculate at will without physical contact?

Note: In this question, I'm asking about animals that have a penis that functions very similarly to humans. I've read some animals have dramatically different methods of copulation and physiologies, ...
5
votes
0answers
53 views

What are these balls in meshopyll cells? [Plant biology]

Anybody knows what are these small balls? The picture was collected with a confocal fluorescence microscope. These balls have a green epifluorescence and they are in mesophyll cells of rice leaves.
5
votes
0answers
94 views

Can anyone identify this seed or nut?

I found many of these nuts in a botanical garden in Sweden (outside, not in a greenhouse) but was unable to find the plant it belonged to. The garden has species from all over the world. I don't ...
5
votes
0answers
73 views

Do brain consume more energy when stressed or Anxious

When a person is anxious or stressed or suffering from chronic depression, it is observed that the person is usually tired. Is there there a connection between fatigue and racing thoughts/obsessions. ...
5
votes
0answers
95 views

Is it Bufo bufo?

I find a couple of frogs. It was cca. 4inches long and 2inches wide. Photo was taken in Prague, Czech republic, middle Europe.. Same zoomed.
5
votes
0answers
122 views

Polyploidy, or why plants of different species can produce fertile offspring hybrids more frequently than animals?

This site says: Plants hybridize much more frequently and successfully than animals do. [...] Chromosomal doubling (polyploidy) occurs more frequently in plants and facilitates the fertility of the ...
5
votes
0answers
53 views

Snail species identification from the United Kingdom

Can anybody identify the species of this snail? From this website, it looks like a Common Snail. Could it be the dextral type of Cornu aspersum? These snails have been found in a garden, have ...
5
votes
0answers
75 views

is this a soft coral on sand?

Was diving a few days ago at Jervis Bay (Australian East Coast - temperate). Water temp 20 degrees C, depth 5m. Spotted this creature in the sand. About 150mm high. It isn't sea-pen (Cnidarian) as it ...

15 30 50 per page