7
votes
2answers
148 views
How to compute properties of peptides ?
I have been tasked with writing a program for computing properties of a give set of peptides. These peptides are given as 1-letter amino acid sequences and I need to compute the following :
Length ...
5
votes
1answer
78 views
Cell proliferation limit and senescence of embryonic stem cells and fibroblasts
I am trying to understand the importance of proliferation limits and cell senescence. In particular, I would like to compare the proliferation limit of Embryonic Stem cells (ES) and fibroblasts (which ...
5
votes
1answer
147 views
Computational/mathematical models for predicting phenotype from genotype
Karr, Sanghvi, et al. (2012) propose a whole-cell computational model for predicting phenotype from genotype in Mycoplasma genitalium. Their model simulates myriad cell processes such as DNA ...
1
vote
0answers
40 views
Text/resource with information on all skeletal muscles and their motor units
Something analogous to an encyclopedia on baseball players with a list of all thier stats would be ideal.
I'm not looking for just generic muscle names, locations and illustrations.
Good answers ...
3
votes
1answer
59 views
Would a plant survive if it was watered using hard-water?
Hard water is water with high mineral/salt content. I'm told that a potted plant watered with a salt solution dries out sooner or later. Is this true?
If so, would a plant survive if watered using ...
3
votes
2answers
163 views
Short-term Lamarckism in asexual single cell organisms
I was reading through the Karr et al. (2012) whole-cell computational model. One of the things they did was to induce single-gene disruptions in their model. They observed several to be fatal, but:
...
3
votes
2answers
90 views
Does body mass have a bearing on reflex speed?
A reflex is an unconscious action in response to some specific stimulus, e.g., blinking an eye, or pulling the hand away from a hot pin
I know from school biology, and reading online that withdrawal ...
2
votes
1answer
620 views
What negative effects can pinhole glasses have on the body?
While shopping in the local supermarket yesterday, I was surprised to find this display on one of the shelves.
I also realize that I should have taken a pamphlet with me, as well as a picture of ...
2
votes
1answer
76 views
Circulation through the liver in light of drug metabolism
I have a lingering question which stems from an answer that I gave to What hydrolyses aspirin within the digestive tract and blood stream?
When a drug or any other substance is absorbed into the ...
1
vote
0answers
209 views
Identify hideous large flying insects on my screen door in Albuquerque [closed]
Last night and tonight, I heard things bumping into the side of my
house (sounded like small rocks).
Last night, I saw some creatures flying around, but didn't get a good
look.
Tonight, there ...
5
votes
1answer
96 views
What are the white dots on the tree in this photo?
Today in Kongens Have, I noticed a lot of white dots on bark of trees. There are plenty of them, and they were usually on 'bottom' side of branches. Does anyone know what this could be?
I took a ...
7
votes
1answer
93 views
What role does a protein's size have on protein-protein interactions?
Protein-protein interactions are when two or more proteins bind together, possibly for some important biological function. Recently, I'm starting to look more into proteins, and in particular, ...
8
votes
1answer
121 views
A timeline of the odds for survival for fertilized eggs and fetuses
I'm looking for data to build a timeline of the odds for survival of a fertilized egg, i.e.,
What are the odds it'll last a week?
What are the odds it'll last a month?
2 months?
(and so on ...
10
votes
1answer
179 views
How does evolution produce complex organs
I've been wondering lately how evolution manages to produce complex organs. It is pretty obvious to me how evolution would select some minor traits like size, resistnce to illness or climate. There is ...
6
votes
2answers
320 views
If body temperature is 37°C (98.6°F), why are most people more comfortable at around 21°C (70°F)?
It may be different for other people, but for me, anything above 32°C (90°F) is very uncomfortable, and my body is inclined to seek cooler temperatures. But I would think that at 32°C, the body would ...
1
vote
0answers
112 views
How do optical illusions work? [closed]
Hello fellow investigators
I have two questions about optical illusions
1) A photo mosaic is something like this http://i.stack.imgur.com/Pzplp.png
What are the optical principles behind our eye ...
4
votes
1answer
94 views
How and when did a dedicated immune system evolve?
I have recently been doing a lot of research into the interplay between the innate and adaptive immune systems in humans, and mammalian laboratory models. This has led to my reading some interesting ...
2
votes
0answers
41 views
Are there any situations in which phenylephrine is preferred to pseudoephedrine?
In the mid 2000s in the US, due to issues of drug enforcement, pseudoephedrine containing medications were brought behind the pharmacy counter and in most cases require ID, and phenylephrine was ...
6
votes
1answer
68 views
Genetic Diversity and Adaptation
I am somewhat new to evolutionary biology, having studied it on my free time as a computer science student. There is one particular thing that has always bothered me for which I have not seen a good ...
10
votes
2answers
133 views
How did the nucleobases in the Murchison meteorite form?
The Murchison meteorite is an important piece of evidence for abiogenesis, because it contained nucleobases from extraterrestrial origin, as this Wikipedia article explains.
These results ...
5
votes
2answers
277 views
Why insects are so energy-efficient while flying?
Why are insects so energy-efficient while flying? Is it because of their light weight and aerodynamics or due to very efficient biochemical transformations (food->energy)?
3
votes
2answers
117 views
Do the simplest bacteria have ribosomes and helicase?
I find it interesting that all life on earth use DNA. I've seen video on how helicase and ribosomes work together to copy DNA sequences (to RNA) with helicase then recreate them using ribosomes. Does ...
8
votes
3answers
2k views
Why can't the brain and red blood cells use fuels other than glucose?
The question is rather straight forward: I have always been curious as to why, but cannot find an explanation online.
I can imagine that the mechanism is different for each, but why does brain tissue ...
14
votes
2answers
917 views
Why is glucose our primary source of energy?
Is there any evolutionary reason for glucose being the "main" molecule used as a source of energy, beginning with glycolysis and subsequently cellular respiration (after being converted to two ...
10
votes
1answer
104 views
Does stress physically age our body?
Going by the assumption that stress eventually triggers a flight/fight response, and the subsequent realization that flight/fight puts the body in a system of readiness to use it's available resources ...
3
votes
7answers
258 views
Introductory books about evolution
This days I read some debates on evolution. That made me more interested to read something reliable on topic - I mean books.
I'm christian - although I think it doesn't matter on that topic - and I ...
7
votes
1answer
50 views
Sequence of ribosomal RNA
Is it possible to sequence rRNA directly, that is, using the ribosome rather than the DNA from the nucleus? For example, this paper, Complete nucleotide sequence of a 16s rRNA gene from E. coli, ...
4
votes
0answers
102 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
72 views
If you had no water supply, is there enough free water in urine to sustain hydration? [closed]
You are in a place where there are no water. And you drink your last water, so you will urinate.
If this were the only available liquid to you:
Is there a limit to the extent to which your kidneys ...
5
votes
1answer
99 views
Why is the human body able to repair a broken bone and not a heart muscle?
The human body can repair skin/organ laceration, fractures, even repair nerves - albeit the duration and rate of recovery differ. For instance:
The burn scar on my arm from the hot soldering iron ...
1
vote
0answers
20 views
Are open grounds in the vicinity of new construction more prone to waterlogging? [closed]
In my experience as open grounds are paved over by new concrete work other grounds yet open are proportionately more water-logged after heavy rain. Over time trees in such water logged grounds too die ...
7
votes
1answer
76 views
How does Yeast-two-hybrid detect interactions between several proteins in one experiment?
I am trying to understand the Y2H screening method. I can understand how we can check if two specific proteins interact with each other. For example, if we want to check whether protein A and protein ...
2
votes
0answers
108 views
What is the proper quick freezing /snap freezing protocol for pancreatic tissue?
I would like to do a quick freeze on pancreases from mice. I want to then make sections (30 µm thick). The idea is to preserve a fluorescent staining done in vivo.
I do not know if I should place my ...
3
votes
1answer
68 views
Predictable microchimerism
I read in New Scientist recently that microchimerism occurs between previously born siblings and grandparents, not just the mother.
Do we know which parts of the genome are likely to be transferred? ...
3
votes
1answer
97 views
How do I create a probe for in situ hybridization?
I tried to make the probe several times but it failed again and again. It usually turns out that the probe after hydrolysis is very very short (maybe around 50bp). I did not check the RNA before ...
4
votes
1answer
172 views
Lifespan of connective tissue cells
This post is regarding a follow up on my initial post on "Properties and life cycle of chondrocytes and tenocytes".
I am elaborating on my question on the lifespan of tenocytes and chondrocytes.
...
4
votes
2answers
63 views
Intrinsic apoptosis in erythrocytes
With a lack of mitochondria, can red blood cells perform intrinsic apoptosis and do they have another way of generating cytochrome c to attach to a CARD domain and assemble the apoptosome?
Or are ...
9
votes
1answer
66 views
Are rods/cones rejuvenated periodically?
Pretty much what the title states.
Some cells/structures in the human body undergo rejuvenation periodically by flushing away older cells and growth of new ones.
E.g Skin, Blood
Does this (for want ...
3
votes
2answers
119 views
JMol “calculate HBONDS”: which atom is the donor/acceptor?
JMol can be used to identify Hydrogen bonds in proteins by the script "calculate HBONDS". By outputting the state of the network, we can obtain a lisdt of H-bonds.
Here's one line from an example ...
4
votes
1answer
61 views
What's in a Name: Statistical Genetics
The novice often performs population calculations using
what is referred to as Mendelian Genetics. Soon after the
publication of Mendel's results; Hardy and Weinberg presented
their results after the ...
4
votes
0answers
36 views
Does a mydriatic drug neutralize the action of a miotic?
If a person were administered a mydriatic, would the subsequent application of a miotic neutralize the action of the former? If the sequence were reversed would a mydriatic neutralize the effect of a ...
8
votes
2answers
110 views
Is there an “evolutionary species similarity calculator”?
Is there a website where I can input pairs of species and get an "evolutionary similarity score"?
E.g. (numbers are completely made up)
Input: Chimp and Human, Output: 97%
Input: Cat and Human, ...
2
votes
1answer
111 views
Negative feedback in the fructose metabolism in liver
What happens in liver when large amount of fructose is consumed?
I vaguely remember my biochemistry lecturer telling us that the enzymes that process fructose in the liver does not have negative ...
9
votes
1answer
89 views
Protein data bank syntax: Can two protein secondary structures “overlap”?
I have a technical question regarding the syntax in Protein Data Bank files. In the protein with PDB# 1AE9 (pdb file), there are two lines in the .pdb file:
...
2
votes
1answer
363 views
What is the “lifecycle” of an average eschar and what types of cells are involved in each stage?
(after some deliberation in the comments, I've decided to make the question more general)
An eschar or "dry scab" often forms at a site of injury over a large cut or sore.
It seems as though the ...
6
votes
0answers
72 views
Does artificial high intensity light damage permanently dark ecosystems?
Popular science features on wildlife typically capture camera images using natural light, or high-speed exposures. This is not possible where the ambient light is extremely poor.
E.g. Caves, Undersea
...
0
votes
0answers
106 views
What makes a cockroach able to survive in a sewer when there is a big weakness point for them: their respiratory hole
What makes a cockroach able to survive in a sewer when there is a big weakness point for them: their respiratory hole?
I know that when i wipe soap water on their respiratory hole, later on, those ...
0
votes
1answer
262 views
Does cockroach lay eggs in human flesh when they “bite”?
Recently, i have "bite" by cockroach, not only the "bitten" area red and swallowing, and more specificly, it have a big hole in that area, when i clean it with hydrogen peroxide solution, something is ...
4
votes
1answer
123 views
Why would deers keep crossing a river full of crocodiles while some of them have been killed?
I recently watched a clip on Discovery Channel, where I saw deers crossing a river full of crocodiles, ignoring the fact that some of them would have been killed doing so.
What could be an ...
0
votes
2answers
151 views
Do cockroaches have less health issues than humans?
Cockroaches are known to live in very dirty places like sewers. Does this cause them to evolve to be stronger against parasites and bacteria? Recently I read online that cockroaches can sustain ...
