17
votes
4answers
1k views

How to understand influenza strain designations?

What do the strain designations for flu mean? For example avian flu is classified as H5N1, what do the letters H, ...
17
votes
4answers
2k views

Why are there species instead of a continuum of various animals?

As I understand it, various animal traits have to evolve gradually, but what happens to the species that are "neither here nor there"? To put it differently, if a species evolved from another, it did ...
17
votes
2answers
400 views

How is temperature sensed?

Can anyone summarize the mechanism by which when an object of a given temperature is placed in contact with, say, the skin on a human fingertip, the average speed of the particles of the object is ...
17
votes
2answers
2k views

Which organism has the smallest genome length?

Which animal/plant/anything has smallest length genome?
17
votes
4answers
1k views

How do trees manage to grow equally in all directions?

I was walking down a road with these beautifully huge trees when this question occurred to me. Large trees with many thick branches have to grow equally in all directions, or they would tip over. Is ...
17
votes
3answers
996 views

How does the immune system “learn” from a vaccine?

According to Wikipedia: A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe, its toxins or one ...
17
votes
2answers
323 views

How does the microbial environment in your gut initiate?

Clearly, a zygote does not harbor any microbes. As it develops, and the alimentary canal tissue is differentiated, I logically assume that there is still no microbial activity in the fetus's gut. I'm ...
17
votes
1answer
825 views

Is kissing a natural human activity?

The word natural here is meant in contrast to it being a sociological construct. Is kissing in all its forms something natural for humans? Is it instinctively erotic? Or is it just a conventional ...
17
votes
2answers
296 views

What are the major evolutionary pressures for Bioluminescence?

What are the major evolutionary pressures for Bioluminescence?
17
votes
2answers
2k views

Do gene expression levels necessarily correspond to levels of protein activation?

I have seen a lot of research into molecular mechanisms of diseases/phenotypes use measures of RNA as a 'proxy' for the level of protein available in the cell. Is this actually valid? My problem ...
17
votes
2answers
3k views

What is the mechanism behind “acquired” alcohol tolerance?

I can understand natural variation in alcohol dehydrogenase (ADH) in a population leading to variation in rate of inebriation (after controlling for other variables -- e.g., mass, food consumption, ...
17
votes
4answers
2k views

Why are there exactly four nucleobases in DNA?

Does someone know why DNA is composed of four nucleobases? In particular, is there an explanation for the number? Why four and not two, or eight?
17
votes
3answers
220 views

How crowded is the bacterial cell?

I was wondering what is the protein concentration in an E. coli cell. When studying enzyme kinetics and activity in vitro, I would argue that the substrate and enzyme concentrations resemble those in ...
17
votes
2answers
376 views

Smallest viable reproducing population

What is the smallest viable reproducing population, such as in a human population. By viable I mean a population which keeps genetic defects low (enough). A very strongly related question: what is ...
3
votes
2answers
67 views

Do women experience more bonding hormones than men after sex?

Does Oxytocin (or any other bonding hormone) increase more so for women than for men after sex? Someone told me that it increases 4-fold for men and 12-fold for women (unconfirmed). Is there any ...
3
votes
1answer
38 views

Mammal body density

Human body density is approximately 1 kg/l (same as fresh water) - which is not surprising (at first) given that we are 70% water, and is surprising (on a second thought), given that the other 30% can ...
3
votes
1answer
64 views

Why do hummingbirds build nests with live ferns instead of dead materials?

Hummingbirds prefer to build their nests with spore-bearing ferns, and mosses. This is helpful for the reproduction of the ferns, which are then better able to spread their seeds. But how is this ...
3
votes
1answer
118 views

What are centromeres *really*?

I've gathered that a centromere is a a region* where the DNA is bundles up even tighter (around protein different to Histone) and chromatids are 'joined'. However I'm still mostly in the dark ...
3
votes
1answer
189 views

Why do carrots spoil so fast?

The carrots we buy from a supermarkets spoil very fast, albeit giving many consumers a false sense of preservability due to their structural rigidity. The answer extends to many other vegetables many ...
3
votes
1answer
26 views

Verifying Protein Folds

I have recently begun using Folding@Home and I am curious how people are prevented from cheating the system. It seems to me that unless the final result is easily verifiable users could submit bogus ...
3
votes
1answer
45 views

how can a pseudo coelomate like ascaris lay 200k eggs in a single day

as per this site the dimensions of eggs of ascaris lumbricoides are 78-105 microns and as it is shown in the pic down here only half of the body cavity would be used for storage of all the stages of ...
3
votes
1answer
49 views

Identifying internal structures of dissected fish

Note : Images displayed below might be disturbing to some people. I have dissected a fish for the first time ! I have some idea of what some of the structures might be but I am not sure and so would ...
3
votes
1answer
13 views

Is there a realistic “family tree” model for the human population?

I would like to do some gene inheritance simulations, and I was wondering if there is an accepted model for what mating looks like in the general human population? I am not necessarily looking for the ...
3
votes
0answers
21 views

Does a presence of ants on a plant mean that the plant has been infested by aphids?

Ants protect aphids from their predators (such as ladybirds): Aphids and other hemipteran insects secrete a sweet liquid called honeydew, when they feed on plant sap. The sugars in honeydew are a ...
3
votes
2answers
56 views

Does a reduction in stem cells mean possible earlier death?

The basis of this question relies on my understanding of these 2 facts: ...
2
votes
3answers
88 views

What equipment would one use to modify a virus? [closed]

Would anyone be so kind as to give me a few examples of the equipment involved when modifying a virus? Otherwise my novel may end up reading Eva entered the lab and modified a virus. Not much back ...
2
votes
2answers
272 views

DNA is charged negative. Where is all the positive charge in my body?

DNA is charged negative. Where is all the positive charge in my body?
2
votes
2answers
33 views

Conservation Genetics - Book recommendations

Can you please give me some advice for a book in (evolutionary) conservation genetics that offers an in-depth review of the mathematical formulations used in this field. I read the book Evolutionary ...
2
votes
1answer
36 views

Standard datasets for testing new multiple sequence alignment algorithms?

Are there any open and freely distributed standard datasets for testing new algorithms for multiple sequence alignment?
2
votes
1answer
52 views

Two-fold cost of sex and r/K selection theory

This article cites a bunch of articles (I haven't been through them) that the effect of the two-fold cost of sex is "reduced" in stable environment or in K-selected environment. It says: [..] the ...
2
votes
1answer
39 views

What is wrong with this analogy: Individuals are to alleles what governments are to individuals

I'm an amateur when it comes to genetics, I'm hoping to learn something from the corrections. I am taking epigenetics into account (kind of); all 3 entities are susceptible to external physical ...
2
votes
0answers
16 views

What does salt do to styes?

Styes formed in the eyes are cured by dabbing at them with lukewarm water(I saw this being done many a times as a home remedy.) At times, common salt is added to the water before dabbing. My mother ...
2
votes
0answers
18 views

How to remove bad lanes in ImageJ Westernblot analysis

I use ImageJ to do an analysis of a Westernblot Image. If everything goes as wanted the workflow is fine. But if I do something wrong creating a lane there is no undo for a lane and also no way to ...
2
votes
0answers
44 views

How to track and describe the evolution of a gene?

So I have a project student (undergraduate) who has been assigned a project to study the evolution of a gene (and possibly related genes) through species. I am not an evolutionary biologist, and hence ...
2
votes
2answers
55 views
+50

What is the difference between drought resistant non-succulent plants and plants that cannot be allowed to dry out?

What features make one plant able to withstand dry spells better than another with relatively similar structure? For instance, one of my Rudbeckias is wilting from drought at the moment, and an ...
1
vote
2answers
34 views

Recommended sequence clustering algorithm for transcriptome data

I'm working on a project where I'm going to analyze a large amount of transcriptome data. After assembling our RNA-Seq reads into contigs using Trinity, it looks like I'm going to have about 10GB of ...
1
vote
1answer
29 views

Does documentation exist that shows the evolutionary connection between common horses and the okapi?

I'm trying to put together some documentation on the relation between the common (modern) horse and the okapi. I've found a tree that shows that connection but it has no references. I'm hoping that ...
1
vote
1answer
28 views

Anaphase Microtubule Disassembly

Centromeres move toward the poles as the microtubules that connect them shorten. This shortening is due to the removal of tubulin subunits from the kinetochore ends of the microtubules. I'm confused ...
1
vote
0answers
4 views

How to measure trajectory regularity?

I have two animal running trajectories. A regular one with repeated back and forth running between point A and B, like the one on top in the figure. The other one is very irregular, animal paused and ...
1
vote
0answers
11 views

What makes certain obligate anaerobes viable in fermentation starter cultures?

If Propionibacterium are obligate anaerobes (to wit, poisoned by oxygen), what makes 'Dairy' or classical propionibacteria (e.g. P. shermanii, P. jensenii, P. acidicpropionici, et al) viable in ...
1
vote
0answers
42 views

Can two women have a daughter? [duplicate]

In vitro fertilization is a pretty routine procedure in which a female egg is fertilized by sperm outside the body. Recently apparently there has also been something similar in which the genetic ...
0
votes
2answers
37 views

Questions about the Evolution Theory [on hold]

I'm trying to understand more about evolution theory. (I am coming from a mathematical background) What i understand till now is that the "improvement" of the dna is a purely random development and ...
0
votes
2answers
93 views

How do download a list of the gene length of all genes?

I would like to get the gene length information of all the human genes. Is there a quick way to get this information? Thank you!
0
votes
2answers
185 views

Deterministic model of lambda-phage lysis/lysogeny [MATLAB] [on hold]

Project 1 Base: Can someone please help me understand what I need from Project 1 Base code to do questions 1 and 2 from the first image? I'm new to MATLAB so a thorough explanation would be ...
0
votes
1answer
68 views

Why to choose a grammar from a lot of grammars that can describe structure of proteins? [on hold]

Why do we choose a grammar from a lot of grammars that can describe structure of proteins? Usually, there are a lot of (maybe infinite) grammars that can describe one language. Why do we choose a ...
0
votes
0answers
4 views

naturally occuring fatty acids

The double bonds in naturally occurring fatty acids present in our body are in cis configuration while the enzymes for beta oxidation can act on trans double bond.Then what will be the significance of ...
0
votes
0answers
4 views

Books for biology,popular but rigorous?

There are very goods in physics and mathematics (like Feynman lectures for exemple) that give an elementry but but broad view of their,therefore I'd like for help to find help to find a biology book ...
0
votes
0answers
5 views

Based on which criteria should i choose the calibrator sample to calculate delta_delta_Ct

I want to calculate the gene expression of an experiment with the Delta delta Ct method. Two files with results of a real time PCR has given to me. The first one has the results with primers for ...
-2
votes
1answer
36 views

What organism most efficiently coverts a given quantity of mass into heat? [on hold]

Question I am trying to answer: In the popular film The Matrix, heat given off by humans is harvested as an energy source. I wondered, if this were possible, would humans be a good organism to ...
-5
votes
0answers
31 views

Wild Boar: Ways they can harm humans [on hold]

How can a wild boar injure, seriously injure or kill a human being, given that the human is conscious/ awake and fully able? That's all, thanks! EDIT: Understanding that a wild boar's weight could ...

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