Questions looking for clarifications or definitions of biological terminology.

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3
votes
1answer
414 views

What is the definition of “dry weight” and “dry cell weight”?

As I understand it, the dry weight of something is its weight minus the weight of its water content. Is this the definition? What about dry cell weight?
1
vote
0answers
43 views

On the definition of gDCW (gram dry cell weight)

I need some clarification on the concept of gram dry cell weight. The unit acronym gDCW stands for gram dry cell weight. My interpretation is that 1 gDCW is equivalent to 1 gram of dry cells, but I ...
1
vote
2answers
68 views

Transitivity of Species Definitions

There are many definitions of "species" which usually take the form Two individuals are of the same species if ... An implied (rarely made explicit) property of any sensible species definition ...
1
vote
1answer
40 views

What is an on-line measurement? What is an off-line measurement?

See it used here: http://en.wikipedia.org/wiki/Fed-batch. In the table giving the different strategies to control growth in a fed-batch culture, one finds, for example: "on-line measurement of ...
5
votes
3answers
1k views

Do apes and humans share 99% of DNA or 99% of genes? What is the difference?

I made an answer on the Scifi.SE that can be read here. It is about how the characters in the story Jurassic Park might have gotten DNA for all the species shown. In my answer, I said this: Apes ...
2
votes
3answers
638 views

Polymorphism in cnidarians?

To me, the phenomenon of polymorphism in cnidarians is particularly troubling. I gather that it essentially refers to existence of various different forms or kinds of individuals, i.e. zooids and ...
2
votes
2answers
289 views

What is a cortical circuit?

I have read about cortical circuits in the context of connectomics (e.g. any example here) and computational neuroscience (e.g. any example here), but a simple Google/Wikipedia does search not show an ...
1
vote
1answer
266 views

What is the difference between abiogenesis and spontaneous generation?

As we all should know, abiogenesis and spontaneous generation are far from identical. For one, spontaneous generation was disproven with Pasteur, and abiogenesis seems to be a solid scientific theory. ...
3
votes
2answers
310 views

What is an organism?

The definition of an organism Wikipedia gives is An organism is any contiguous living system. I understand that these are not organisms according to this definition: A bird and a tree it's ...
6
votes
1answer
59 views

Can an organism obtaining a part of its genome via horizontal gene transfer be called a “hybrid”?

Wikipedia definition of "hybrid" offers many competing definitions. But most seem to be centered on sexual-reproduction gene transfer. Is there an official (in a textbook or widely accepted peer ...
4
votes
1answer
81 views

How would one describe the R-factor in crystallography?

Yes, there is the wikipedia definition, but how would one explain this concept to a non structural biologist?