All Questions
2
votes
1answer
60 views
Does this patient have HHV6 or HCMV after transplant surgery?
I have been given mock results from a PCR test on blood samples taken from kidney recipient patients and their donors. The PCR reaction can detect single copies of viral DNA. I have been asked to ...
1
vote
1answer
24 views
How can I learn about how cloning works in nature (twins)?
I would like to learn about how the process of cloning works in nature - how are twins "created" after fertilization what genetic changes can occur in each of the twins.
Where should I start? What ...
2
votes
1answer
34 views
Autophagy in eukaryotic cells
What is autophagy? How and under which circumstances is it used by the cell? I believe The reason for autophagy is some kind of recycling, am I right? But why does it occur in infections?
1
vote
1answer
15 views
Do nerve cells cause action potential in cardiac muscle?
I think the answer is no, but I am not 100% sure.
If it was yes, then the dendrite of the nerve cell should each time receive a stimulus causing Na+ channels to open, when the contraction happen.
...
5
votes
2answers
127 views
Can proteins move outside cells?
I am trying to learn about basic cell biology, and have what is probably an extremely simple question.
So this is how I understand it so far:
Proteins are made from amino acids. This process is ...
0
votes
0answers
39 views
Change in conditions of an ecosystem lead to change in organisms
Let's think about the slash and burn method and its effects on the ecosystem.
Cutting down trees that rise all the way up to the canopy would expose the plants at ground level to more light, so would ...
1
vote
1answer
20 views
Which hormones/factors affect Calcium absorption in the small intestine and its regulation?
I think the question is very broad and cannot find precise mechanisms.
I am not sure about the precise mechanisms of the regulation.
I think they are at least Vitamin D, diffusion and specific ...
1
vote
1answer
24 views
Can songbirds mimic car alarm sounds?
A silly question. A few days ago I observed a very vocal bird with impressive vocal variety. It was rapidly switching from one tune to the next. After sometime I realized that the bird might be ...
1
vote
0answers
22 views
By what mechanism does elevated homocysteine level cause endothelial dysfunction and damage?
It has been stated that elevated homocysteine level causes endothelial dysfunction and damage. By what mechanism does this happen?
5
votes
1answer
66 views
Is human face more resistant to cold than other body parts?
Walking outside tonight in -15˚C I realized an interesting observation: While I felt cold on most part of my body, my face (although the only uncovered part) didn't really feel cold. It registered the ...
6
votes
1answer
93 views
Does muscle growth trigger angiogenesis?
So heavier people generally have more blood than lighter people (this is why heavier people generally need to take higher doses of medication for the same effect of medication). They also have more ...
3
votes
2answers
47 views
Just how light-sensitive is ethidium bromide?
One lab I was in was paranoid about keeping it in a foil-wrapped conical tube; my current lab leaves it out on the bench (and it works fine for staining gels). It's the same company/concentration in ...
3
votes
1answer
33 views
Plasma cells and memory cells
What decides whether an activated B cell will get converted to plasma cell or memory B cell? Is it necessary that out of a mitotic division one will convert to memory B cell and the other to plasma ...
3
votes
2answers
58 views
Do we have enough diversity of antibodies to overcome almost any antigen?
I always wonder about the capability of diversity of our antibodies. Do we have enough antibodies to fit to every kind of molecule? Wont't it be easier if our antibodies are like clay and can be ...
2
votes
1answer
83 views
Comparing BLAST and the Smith-Waterman algorithm
I've been asked: how does BLAST improve dynamic programming accuracy?
I do know that BLAST is based on heuristic approach that approximates the Smith-Waterman algorithm and that the Smith-Waterman is ...
2
votes
1answer
63 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. ...
6
votes
1answer
79 views
Same 185th million grandfather?
I was watching a lecture by Richard Dawkins earlier today and he mentioned that “Your 185th million grandfather was a fish.” I started wondering about the following question,
Is it true that my 185th ...
4
votes
0answers
35 views
Is it possible to condition the body to reduce bruising?
I do combat sports, and in these sports there are a lot of hits that can cause bruising.
I've found that, over time, physical conditioning can reduce and/or eliminate the bruising to the point where ...
-4
votes
0answers
29 views
Less Evolved Humans? [closed]
In Homo Sapiens we see that evolution caused the dense hair growth to be altered to a more fine growth of hair on the body( at parts like hands and feet)..
Therefore can we assume that people having ...
2
votes
2answers
94 views
Prenatal Marketing
This is for a short story idea.
Is it possible to modify the DNA of a child to make their metabolism more susceptible (physical response, addiction, etc) to a certain type of chemical i.e. a chemical ...
0
votes
0answers
21 views
Avian Diseases : How to Disinfect
How can I sanitize a bird's carcass so that no diseases are present after disinfection? I was thinking $\gamma$-ray bombardment since ozonation would only surface disinfect.
6
votes
1answer
39 views
Intracellular lipid transport
I know that lipids are carried around the body in the blood either as micelles or by lipid-binding proteins which allow them to be solved.
Lipids can't always be integrated in a membrane though, the ...
5
votes
1answer
129 views
Using ion-exchange chromatography to purify DNA from a cell extract - Is DNA more negatively charged then RNA?
When applying this method we have a glass or plastic column of resin which is positively charged. Then we pour cell extract into the column in order to capture the negatively charged particles which ...
1
vote
2answers
52 views
General undergraduate zoology textbook recommendation?
I am very interested in zoology,and I want to study zoology in my spare time.
Any undergraduate level zoology text book recommendation?
-2
votes
0answers
29 views
How to use the maximum potential of our brain? [closed]
I am not a biology expert. This is a general question, I watched the movie Limitless is there any truth about the pill he is using.
Any way, How to use the ...
3
votes
1answer
36 views
Does retinal detachment happen more frequently at night?
My understanding and experience is that during the night photoreceptors are less tightly coupled to the retinal pigment epithelium. Does this make it more likely for a retinal detachment to happen at ...
1
vote
1answer
26 views
What's seen when stress echocardiography shows ischaemia? Can this happen without angina?
What can be seen on the screen when stress echocardiography (a pair of heart ultrasounds before and after exercise) suggests ischaemia? Can this happen without chest pain?
Illustration from ...
2
votes
0answers
40 views
Movement of stem cells from mother to fetus
Recent results from J Lee Nelson and colleagues (Sci Am. 2008 Feb;298(2):64-71; available as full text through Google) show that cells from the mother were found in a person aged 46. Logically, these ...
7
votes
0answers
93 views
Do the majority of fish lack scales on their heads?
Based on pictures, it seems to me that a vast majority of fish species that have scales do NOT have scales on their heads.
Is that fact true?
To make this properly answerable:
lets' define a ...
2
votes
1answer
30 views
What are ways to compare the “costs” and “gains” of food production systems?
I'm looking for methodologies to compare the costs a food production requires with the gains it delivers (not in economic terms).
I'm aware of energy returned on investment. Are there other methods ...
3
votes
1answer
24 views
How do different tissue culture matrices affect background in fluorescent microscopy?
In response to my previous question, I've been reading up a little bit on poly-D-lysine, Collagen I, Collagen IV, laminin, and other tissue culture coatings that promote cell adhesion. I've always ...
2
votes
2answers
53 views
Evolution after the development of sexual reproduction
My understanding of evolution is that genetic mutation occurs in individual members of a species, and they become a new species.
Isn't a definition of species a group of genetically similar organisms ...
6
votes
3answers
125 views
What reasons allow for women to outlive men?
It is a well-known fact that women tend to outlive men.
I often hear people unscientifically stating that men generally generally die younger because of the higher stress encountered in their work ...
2
votes
1answer
45 views
bind antibodies to study properties
I am interested to experimentally look at the behavior of antibodies. To do so, I need to be able to bind these antibodies somewhere on a sample. does anybody know of a good sample to use where ...
4
votes
1answer
55 views
Measuring sugar content of a tree
I would like to grow mushrooms on oak trees I can harvest from my property. I've read that the best results will be when the sap is rising but the tree hasn't budded yet. The mycelium feeds on the ...
3
votes
0answers
52 views
Food Intake versus ability to flee among birds, particularly the hummingbird?
Logically speaking, if a hummingbird drinks too much nectar, it will be temporarily overweight and less able or unable to fly to escape danger. However if the same hummingbird doesn't drink enough ...
1
vote
1answer
28 views
Can you cure allergies?
A common solution is allergy shots, which helps you adapt to the allergy. But are there ways to tell the body that this allergy is safe and there is no need to amount a response to it? So that there ...
1
vote
0answers
14 views
Do antidepressants with their BDNF expression-increasing effects display disease-modifying effects in Alzheimer's disease?
I ask this question because I've looked everywhere I can think of and not one mention of this even though it definitely makes sense based on the finding that antidepressants increase brain-derived ...
4
votes
1answer
43 views
What determined the evolution of different faces in humans?
The most distinctive characteristic of a human is it's face - it is unique among each individual (with the exception of identical twins). It is uncertain to me if whether we best identify other humans ...
2
votes
0answers
26 views
Excretion of monovalent and divalent ions in sharks
I have heard that sharks excrete $\ce{Na+}$ and $\ce{Cl-}$ by their gill surfaces but divalent ions like magnesium are excreted through feces. What could be the reason behind this?
7
votes
2answers
138 views
Does pheomelanin have a useful biological function?
Melanin is a natural pigment that is categorized into two main forms, eumelanin and pheomelanin. It's well documented in the science literature that increased eumelanin levels reduces the risk of ...
4
votes
1answer
50 views
How to convince suspension cells to adhere more tightly?
I'm developing a cell-based assay in 96-well plates that requires adherent cells, as they need to be washed at least twice during the protocol. I'm using in-house strains of HT1080 cells (some ...
2
votes
1answer
44 views
Low complexity region and relaxed selection
I'm reading a text (Wagner, 2007) on identifying positive selection. In paper, the author says that low complexity regions are known to be associated with relaxed selection. I'm trying to understand ...
1
vote
1answer
51 views
How do changes in temperature affect body weight in humans?
What would be effect on weight of individuals if we bring a fully adapted (to cold climate ) human individual and a fully adapted to very hot climate individual to a moderate climate region?
1
vote
1answer
97 views
What is this insect?
These photographs were taken today in Marseille, in the Mediterranean coast of France. My French friends inform me that these beasties are called cousins because they are "cousins" of mosquitoes ...
1
vote
0answers
24 views
What parts of the brain are involved in regulating blood pressure in mammals?
I'm reading this Wikipedia article on blood pressure and its regulation, and it mentions that medulla is involved. however, I vaguely remember reading another article on Wikipedia and it mentioned ...
-2
votes
1answer
72 views
Are we evolving to age slower, or to live longer aging at the same rate?
I wonder why most of us find senior people lovely and charming. Is it because to love grandpa and granny is vital to our survival as a species, in the same way as we love babies? If so, it would mean ...
-1
votes
0answers
20 views
Eco-plasticware for the Vendor of Fruit Flies : An Analysis into Microhabitats and Their Bioplastic Enclosures [closed]
The title may be a bit over-the-top, but I'd like to know if there are any "specialists" in plant plastics which are to be used as enclosures for fruit fly habitats. These habitats will have a small ...
4
votes
1answer
687 views
How does this illusion work?
I found this image on Google+
If you shake your head you can see a portrait of a person. Can anyone explain how the image is constructed in the brain?
2
votes
1answer
39 views
Identify this waterfowl species?
I've been unable to find anything on the Google resembling this bird. I took the photo in Virginia Beach, VA around 2010, October, I think...
It appears to be between winter and summer plumage but I'm ...
