4
votes
1answer
67 views

How fast cancer cells divide, compared to normal cells

This question suggests that we have, on average, 50-70 billion cell divisions per day. I just read that cancer cells divide more often (therefore more prone to radiation). I am wondering, for a ...
0
votes
1answer
45 views

Any relevant knowledge/studies about voluntary goose bumps

I'm not entirely sure how normal this is, but since I was a child, I've been able to produce myself voluntarily a "chill" sensation that seems to start on my head and traverse the rest of my body, ...
1
vote
1answer
30 views

What is the name of the critter depicted in the attached image?

I found a critter on my bathroom towel. It's really tiny. Maybe 2 milimetres? I placed it on an envelope for the photograph. Can someone identify what it is?
18
votes
3answers
1k views

Why do we need red blood cells?

From what I know, the main function of red blood cells is hemoglobin transport. So, why do we need cells packed with hemoglobin: why can't it travel freely in the bloodstream? My own thoughts were: ...
1
vote
1answer
13 views

Lateral corticospinal tract and termination

I'm studying the motor pathways of the brain and I'm a bit confused about how the lateral corticospinal tract descends. From Neuroanatomy: Text and Atlas by ...
2
votes
1answer
92 views

What kind of fly is this?

I found this dude hanging out in my sink, but he didn't fly away when I put a dish in the sink. Turned out it was dead. The front part looks exactly like a housefly. But, I've never seen the back end ...
1
vote
1answer
15 views

Are there multicellular isogamous species?

Are there multicellular isogamous species? Seeking through the examples of wikipedia I would tend to think that there are no multicellular isogamous species.
2
votes
0answers
11 views

How many cells in apical meristem

How many cells are there in the apical meristematic tissue? Looking at this picture... I would tend to think that there are few hundreds (maybe only a hundred) cells in the meristem tissue. But I ...
5
votes
2answers
79 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 ...
3
votes
1answer
139 views

Sporophyte and gametophyte

My textbook says that in both groups of seedless plants (vascular plants, non-vascular plants) the gametophyte is a free-living plant, independent of the sporophyte. I don't understand this statement ...
4
votes
1answer
75 views

Does adding milk to cereal make it harder for our body to absorb the vitamins and minerals from the cereal?

I add about 3/4 cups of Blue Diamond almond milk (unsweetened) every morning to a single serving of Cheerios. The milk contains filtered water, and I read that drinking water with food at the same ...
1
vote
0answers
18 views

What is the difference between rheobase and threshold?

What is the difference between rheobase and threshold? In the definitions I've read it's described as almost the same thing and when I asked my professor he couldn't convince me so can you give a ...
12
votes
2answers
1k views

Why do we like salt?

A few friends of mine told me that salt provides zero nutritional value to us, and in fact can harm our bodies. Now, these guys are medical students, and being an engineering student myself, I decided ...
5
votes
2answers
32 views

Alternatives to trypsin for cell detachment?

I have ran out of trypsin and need to passage my cells (immortalized chondrocytes, C28/I2) today or tomorrow. I have been out of town and forgot to order more trypsin. I was wondering if there are ...
1
vote
1answer
34 views

Which immunosuppression caused by long-term usage of these antibiotics in untreated celiac disease?

These antibiotics include amoxicillin + acidum clavulanicum (beta-lactam, inhibit cell wall synthesis, broad specturm, 3rd gen aminopenicillin) / last part preventing the resistance ceftriaxone (3rd ...
1
vote
2answers
19 views

How does non-homologous end joining (NHEJ) work?

I was reading about non-homologous end joining (NHEJ) in my molecular biology of the gene textbook but the explanation provided in the text was rather vague to me, and I was not able to understand it ...
0
votes
1answer
51 views

About the plight of Elephants and efforts to conserve them? [on hold]

Poachers are only after the ivory horns right? I read this story from the New York Times ( I think) of saving a Rhinocerous by some Park Rangers and a Vet. ( forgive spelling) ; they tranquilized the ...
15
votes
3answers
4k views

Why isn't vomit corrosive?

Vomit comes from gastric acid, right? And in gastric acid there is HCl and HCl is corrosive (strong), how come when I vomit, it doesn't destroy things that it (as the vomit) hits (such as floor, ...
3
votes
1answer
25 views

How are chickens affected by light?

When I was young, I was told never to put a fluorescent light in a hen house because it continuously turns on and off. Extra lighting is used, as far as I know, to 'extend' a chicken's day. Human eyes ...
0
votes
0answers
14 views

Book-recommendation: Economic Zoology

I need to have a book which covers following topics two may also be fine: (a) Apiculture, sericulture, lac culture, carp culture, pearl culture, prawn culture, vermiculture. (b) Major infectious ...
1
vote
0answers
18 views

Like size and colour constancy, why does the brain not maintain focus constancy?

I have progressive myopia. I grew up with perfectly normal eyes but slowly started getting myopic. The thing is, my brain knows (or should know) what the world looks like -- it knows that far away ...
1
vote
0answers
18 views

A good introductory book to histology?

Like the title says, I am looking for a good introductory text to histology. It would ideally cover sample preparation microscopy staining, and several example experiments Suggestions?
0
votes
2answers
48 views

What are the genus and species name of different breeds of dog?

Can you refer me to a good source containing the genus and species name of different breeds of dogs?
5
votes
2answers
41 views

Problems understanding membrane potential

I understand that membrane potential is the difference of the extracellular and intracellular ionic charges, due to their concentrations. We say that the extracellular space has a charge of 0 and then ...
1
vote
1answer
23 views

Are there organisms that have incorporated plastic into their lives?

Are there organisms that have incorporated (manmade) plastic into their lives in any way? Either in their diet, or as a part of their body?
8
votes
1answer
222 views

How do the pharmacodynamics of the NSAIDs differ and are there “resistant” COX phenotypes?

I know that the non-steroidal anti-inflammatory drugs (e.g., aspirin, ibuprofen, naproxen) affect the enzymes cyclooxygenase (types I and II). Is there any difference in the degree to which these ...
0
votes
0answers
24 views

Nystagmus drug FDA approval?

Congenital Nystagmus is an eye focusing disorder. It happens in manuals. Wikipedia lists several treatments on its page. Are any of those FDA approved for human use of that disease. drugs found ...
2
votes
2answers
62 views

peptide MHC microarray

"The recent technology is peptide–MHC microarray or artificial antigen-presenting chip. In this technique, recombinant peptide–MHC complexes and co-stimulatory molecules are immobilized on a ...
1
vote
0answers
18 views

Regarding benign tumors and what 'stops' them

Benign tumors can grow to dangerous size yet are they capable of metastisizing ; if not what stops this? Also with a benign tumor if you call its cells 'near' its edges its tumor 'cell wall' I was ...
4
votes
2answers
66 views

How does protein denaturation work?

I was wondering how protein denaturation works. Are there covalent bonds, such as disulfide bridges involved, or is it based purely on non-covalent bonds such as hydrogen bonds? Why is denaturation ...
5
votes
2answers
893 views

Does cooking or ripening reduce the concentration of solanine in nightshade?

I recall a story from one of my Botany professors where he encountered a woman picking Solanum dulcamara (nightshade) berries. When he asked her what she was doing with them, she responded that her ...
1
vote
0answers
32 views

How to visualize the ECM?

Specifically, I'd like to look at changes in HA (hyaluronic acid) production. Most often you only see people staining the cell surface or removing cells from culture for fixation and then imaging. ...
0
votes
0answers
11 views

are cranial nerves responsible for the fault mechanism [duplicate]

how speech is produce and why people stammer during the speech. What factor is culprite for the fault mechanism? Is it nerves?
0
votes
0answers
22 views

MRI with lots of white matter.

Why might an MRI show a large amount of white matter and a low amount of gray matter yet have a full skull with little shrinkage in an above average intelligence primate?
0
votes
0answers
28 views

Cost of Substitution explained

I've recently come across an article that mentions "Cost of Substitution" and was wondering if someone can give me a real layman's term explanation of what that is. (Edited:) This was in relation to ...
1
vote
1answer
55 views

What are the disadvantages of forbidding flights to and from the African Ebola region?

After looking through the available Stack Exchange sites, this one seems to come closest to the appropriate place to ask... Popular opinion, including my own, is that banning flights to and from the ...
1
vote
1answer
28 views

What are the risk factors of elevating legs for too regularly and when tired?

I started to to think the pathophysiology of elevating legs high next to the wall too often and when you are tired. I think possible manifestations some damage to valves of the veins (No!) because ...
2
votes
0answers
12 views

Why is gynodioecy common and androdioecy rare?

Gynodioecy is when a population features individuals that produce both male and female gametes and individuals that produce just female gametes. Androdioecy is when a population features individuals ...
9
votes
3answers
614 views

The evolutionary process in bird wings, especially with regard to winglets

In this answer on aviation.SE a comparison is made between the shapes of airplanes wings and the shapes of birds wings. It concludes with the following remark: After all, no bird has winglets. Not ...
0
votes
0answers
23 views

are nerves culprit for stammering habit [on hold]

i have been stammering from 9 years old till date[18] . I find different resons for stammering according to people. What is science behind it and how it can reduce?
2
votes
1answer
454 views

Why do humans bury their dead?

As far as we know Ape Men or the Neanderthal Man was the first to bury its dead. My question is why. I don't think they practiced religion or believed in spirits or faith or stuff like that. ...
2
votes
1answer
31 views

Somatic Mutations in meristem tissue in plants

In angiosperm, in which layer of the meristem does a new mitotic mutation occurring has chance to be found in a pollen grain or in an ovule? I also welcome some insights about non-angiosperm plants.
8
votes
1answer
1k views

How long does the Ebola virus remain infectious on contaminated items or surfaces?

I'm sure there will be variation depending on what the contaminated item or surface is made of - linens, I could imagine, would remain dangerous for longer than a door-knob. But if the items are not ...
2
votes
1answer
36 views

What are some of the general characteristics of the DH5 alpha strain?

I can not find some useful sources unfortunately. Please tell me about some important characteristics of DH5 alpha. What makes DH5 alpha suitable for the gene cloning?
2
votes
0answers
23 views

What is the allelic frequency at mutation-selection-drift equilibrium?

At mutation-selection equilibrium the expected frequency $f$ of a given locus is $$f ≈ \frac{\mu}{s\cdot h}$$ , where $\mu$ is the mutation rate, $s$ is the selection coefficient and $h$ is the ...
2
votes
0answers
21 views

Ancestral states of sex determination system

Most (maybe all?) species that reproduce sexually have either genders (anisogamy) or mating types (isogamy). There exist today many different type of sexual determination system. There is a whole ...
2
votes
0answers
16 views

What is most ancestral: isogamy or anisogamy?

Sexual reproduction can be feasible with anisogamy (gametes of different sizes i.e. genders) or isogamy (gametes of same size i.e. mating types) or with undifferentiated gametes (i.e. true random ...
4
votes
2answers
440 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
0answers
54 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 ...
2
votes
1answer
23 views

Does DNA replication in 5' to 3' (leading strand) need RNA primase?

https://www.youtube.com/watch?v=27TxKoFU2Nw In the above video it shows that during DNA replication, the lagging strand require RNA primase to add 3' -OH group for further addition of nucleotides. ...

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