Questions looking for clarifications or definitions of biological terminology.
Questions tagged [definitions]
85 questions
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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 and Humans, for example, share over 99% of their…
frеdsbend
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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 is that the relation "is the same species as" should…
user4810
16
votes
2 answers
Is blood regarded as an organ?
It consist approximately 7 percent of body weight.
By definition organ is composed of multiple tissues. Blood is a fluid, a circulating tissue.
Therefore can we call this fluid system a liquid organ?
kenorb
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Are 'homeothermic' and 'endothermic' synonymous?
I got this question from the comments below this answer. So, do homeothermic and poikilothermic have the same meaning as endothermic and ectothermic, respectively?
A user also suggested that the terms such as poikilothermic and homeothermic have…
user237650
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What is the definition of "Natural Selection"?
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype.
Natural selection, a process that results in the adaptation of an organism to its environment by means of selectively reproducing…
Zuhair Al-Johar
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11
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3 answers
What is the definition of a mutation?
There are two alleles that determine the sensitivity of a person to Coumadin (a medicine for blood thinners used to treat a stroke etc). Sometimes you encounter the terminology that one has a mutation on both alleles (father's and mother's side).…
Marijn
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Can domestic breeding be considered evolution?
Domestic breeding of animals (and plants) by humans seems to match some of the definitions of evolution I have been able to find:
"a process that results in heritable changes in a population spread over many generations." (the TalkOrigins…
Danny Eisenga
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8
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1 answer
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 reviewed work) definition of a…
DVK
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What is the definition of a stringent/relaxed plasmid?
I have found a publication which proposes some definitions, including a definition for strict and relaxed replication. The definitions are:
Relaxed control of plasmid replication. Relaxed control should be used in reference to plasmid replication…
Superbest
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What does "Mutational Variance" mean?
Background
The concept of mutational variance can be found in many articles including this one for example. The mutational variance of a trait number $i$ can be found in the M-matrix in position $m_{ii}$ (in the diagonal). Elements of the…
Remi.b
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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 polyps in one species. But when we refer to the…
stochastic13
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How different are these terms: Phylloclade, Phyllode, Cladophyll and Cladode?
We started with Plant Morphology in class (specifically, the morphology of angiosperms).
My teacher's provided us with the following terms and their definitions.
Phylloclade
A modified stem that is flattened or cylindrical and capable of…
paracetamol
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6
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What is Environmental Robustness? Is it different from plasticity?
Hansen (2006) in his review uses the concept of environmental robustness independently of the other concepts of robustness (at pages 139 and 140) without defining it.
How is the term environmental robustness usually defined?
The concept of…
Remi.b
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Are spiders part of the study of entomology?
The definition of entomology says it is the science of studying insects.
I know spiders are not insects but does entomology include studying spiders as well?
Otherwise is there any name to the science of studying spiders (class Arachnida)?
рüффп
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Problem with an analogy (Cell Membrane)
I'm studying biology for the first time seriously. I've been reading OpenStax College's material.
In the section of "The Cell Membrane", I have the following problem:
Choose the answer that best completes the following analogy: Diffusion is to…
Ana Galois
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