Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [definitions]

Questions looking for clarifications or definitions of biological terminology.

1
vote
1answer
32 views

Actual definition of cardiac output

Is cardiac output the amount of blood pumped by both ventricles in 1 minute or only by the left ventricle in 1 minute?
2
votes
1answer
30 views

Is studying chemical and physical properties of chemical substances that make up organisms really a task of molecular biology?

I have read in a high school textbook that (translated into English by myself): "Branch of science that concerns itself with studying chemical and physical properties of substances that make up ...
-1
votes
0answers
31 views

Can sugars/carbohydrates have 2 carbons?

Why can't $\ce{C2H4O2}$ be a carbohydrate monosaccharide?
2
votes
1answer
107 views

What is the difference between a cytokine, a hormone and a protein hormone?

I'm trying to figure out the difference between hormone, cytokine and protein hormone. It's clear to me that all three are biological messengers, but there seems to some ambiguity and overlap between ...
2
votes
0answers
48 views

What function will survive evolution?

I wrote the following phrase in my scientific text: X is ubiquitous in life of Y. On some occasions X might be detrimental, resulting, for example, in so so phenomena. But is it plausible that a ...
1
vote
0answers
22 views

What is a section in botany based upon?

I am a bioinformatician working with plant data. Therefore my formation on plant biology and botany is "ok" but not very strong. When people talk about sections, I know that they talk about a ...
2
votes
1answer
212 views

Introgression vs admixture

What is the difference between genetic introgression and genetic admixture ? Are these terms interchangeable ? Do they apply to different population scopes or something ? The usage seems kind of vague ...
2
votes
1answer
55 views

How do you define a gene list?

So I wrote in a chapter that I will be checking for publications with gene lists in them. I got a comment asking "How would you define a gene list and what criteria did I use". I know that gene lists ...
1
vote
1answer
108 views

Usage of “lineage” over “species”

Remi.b has suggested here: The concept of species is poorly defined and is often misleading. The concept of lineage is much more helpful. IMO, the only usefulness of this poorly defined concept ...
2
votes
1answer
27 views

What do the column labels in this table mean?

This table shows the effect of sound (song and tones) on female birds. However, I'm not sure what the labels (F1 22, P and η2) mean. I've seen the labels on other tables too. (from https://www.ncbi....
1
vote
3answers
133 views

Evolution as a directed graph exploration?

First of all, I am not biologist, nor good in chemistry/physics. Secondly, I am really eager to understand. So I think of a "life" (of a certain whatever being) as a space of somewhat properties. ...
1
vote
1answer
68 views

Why is a cellular structure necessary to satisfy the definition of alive? [duplicate]

I was looking at this image and reading through the Wikipedia page for viruses and it says that to satisfy the definition of "being alive" the organism must have a cellular structure, but it seems to ...
6
votes
3answers
421 views

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 ...
1
vote
2answers
79 views

What are the major differences between good study habits for biology vs mathematics? [closed]

I'm a math prof. But, I've always loved reading about biology (the paleobiology of microbes and some small animals mostly) it's my hobby but I want to learn more maybe take a course. My longer term ...
6
votes
2answers
4k views

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 ...
15
votes
2answers
3k views

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 ...
1
vote
1answer
24 views

What does endochorous dispersers means?

In an article (Guerrero and Tye, 2009) it talks about endochorous dispersers. Guerrero, A. M., and A. Tye. 2009. Darwin's Finches as Seed Predators and Dispersers. The Wilson Journal of Ornithology ...
0
votes
0answers
354 views

What is the definition of a metabolic interaction?

I struggle to find definition of "metabolic interaction" as in "metabolic interaction network", especially in context of metabolism of a single organism (not like a gut bacteria-host interactions). I ...
1
vote
1answer
916 views

Exact definition of 'convergent' and 'divergence' in cell signalling?

From what I understand, we refer to 'signal convergence' as being when two different ligands/stimuli lead to the same (at least in part) responses inside a single cell. This may or may not be due to ...
3
votes
0answers
45 views

Majority rule definition

In this book, they talk about the majority rule. Majority rule, which retain s the edges present in more than 50% of the trees. They used that rule also in ...
5
votes
1answer
174 views

Can an exotic species be also endemic?

While talking about the evolution and conservation of dingoes in Australia, someone asked an interesting question: Can I define the dingo as an endemic species? That question, despite apparently ...
0
votes
2answers
369 views

What is the philosophical definition of life? [closed]

How does philosophy define life? And how does it overlap and contrast with the concepts and nuances of other sciences such as biology, chemistry, physics and mathematics?
4
votes
3answers
5k views

What is a gene transcript, how is it different from an allele?

Within human genetics, My current understanding of a transcript for a particular gene is that it's the exact nucleotide sequence and position of a particular instance of said gene in some individual. ...
6
votes
1answer
285 views

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 ...
4
votes
1answer
366 views

What is “Peripheral Dogma”?

The book, Introduction to Bioinformatics, by Arthur M. Lesk, 3rd edition; Oxford; low-price-edition; in its chapter-1 (introduction), page-no. 6 ; provided a paragraph, entitled "Dogmas: Central and ...
3
votes
1answer
592 views

The meaning of the $\alpha$ helix and $\beta$ sheets in proteins [duplicate]

I asked this question to my Biology teacher and he, in collaboration with a Chemistry teacher, couldn't find the answer. My question is the following: "What does the $\alpha$ and $\beta$ represent in ...
0
votes
0answers
101 views

Are viruses technically organisms, or not? [duplicate]

Are viruses technically organisms or not? A quick Google search query for the term; are viruses organisms?, reveals various conflicting and somewhat inconclusive ...
0
votes
1answer
674 views

What are the characteristics of a living organism? [closed]

It seemed fairly basic at first, and yet I have to ask because even a quick Google search reveals that it doesn't seem to be quite so straight-forward anymore. After more research, I found multiple ...
0
votes
2answers
244 views

Is there a formal definition of `nature` in Biology?

I've been discussing with a friend about Earth Day and at a certain point came out the question What do you call "nature"? He said that he considers "nature" basically all matter, including ...
5
votes
1answer
311 views

Was Darwin aware of the difficulties behind the concept of species?

Introduction The concept of species is a very old concept that suffers from not being a natural category. There exists no single definition that would categorize living beings into groups and that ...
2
votes
1answer
2k views

What does pseudo-irreversible mean?

In this publication (PDF) I encountered the following word: Binding of rupatadine to histamine H1 receptors isolated from the guinea-pig cerebellum and lung was demonstrated by inhibition of 3H-...
12
votes
3answers
937 views

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 ...
1
vote
1answer
142 views

What would be “Sternum-Intermediate” distance?

I've asked this question on the English Language & Usage board, not being entirely sure whether this question is strictly medical, or just English knowledge suffices to answer. Do note I am no ...
5
votes
1answer
2k views

What is a tardigrade “in tun form”?

While reading this article about tardigrades that had been previously frozen, I came across some verbiage I wasn't sure of and couldn't find any real explanation given the context. The article kept ...
3
votes
2answers
245 views

What is the definition for vitamins?

I have found the following definition on Wikipedia: An organic chemical compound (or related set of compounds) is called a vitamin when the organism cannot synthesize the compound in sufficient ...
1
vote
0answers
51 views

“Signal Advance”: Unsure of meaning or contextual use

I am reading through Recombinant DNA; Genes and Genomes - A Short Course - Third Edition by James D. Watson, et. al. and I came across this paragraph in the discussion about discrete factors of ...
3
votes
1answer
250 views

How do we call a region of low carrying capacity?

I am looking for a convenient word to define a region of the landscape where the local carrying capacity (population size) for a given species is low but different from zero. The species is still ...
1
vote
1answer
1k views

Definitions of common and rare disease

Is there an epidimiological way to define rare and common diseases ?
0
votes
1answer
224 views

Can a relationship exist that is mutualistic/parasitic/etc. but not considered symbiotic?

Wikipedia definition of symbiosis: "Symbiosis (from Greek σύν "together" and βίωσις "living")[2] is close and often long-term interaction between two or more different biological species." Wikipedia ...
15
votes
2answers
20k views

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?...
6
votes
2answers
655 views

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 ...
2
votes
2answers
359 views

Definitions of robustness and canalization

The concepts of robustness and canalization are fashionable today in the biology literature. However, I am not sure of their definitions and I am not sure either that all authors actually use the same ...
6
votes
1answer
764 views

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_{...
5
votes
1answer
3k views

Soft and Hard selection

Seems to me that these two sources (M. Whitlock, B. Wallace) use different definitions of soft and hard selection. M. Whitlock: Soft selection occurs when the relative fitness of an individual is ...
6
votes
1answer
13k views

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 ...
0
votes
1answer
3k views

What the difference between an inverted and everted retina?

I'm looking specifically for examples and comparisons, because the definitions of inverted and everted are remarkably similar; e.g. from Dictionary.com/Reference.com: everted verb (used with ...
6
votes
2answers
8k views

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 ...
1
vote
1answer
534 views

What is a sex-biased gene?

How do you define a male-biased gene and a female-biased gene as they are found in the abstract of this article.
2
votes
1answer
375 views

Definition of Sexual Selection?

How do you define Sexual Selection (SS)? (One might want to subdivide SS into intra- and inter- SS to answer) Is SS clearly different from Natural Selection (NS)? Is SS nested within NS or are NS ...
1
vote
1answer
91 views

What does “developmentally programmed” mean?

What does the term "developmentally programmed" mean? I can't seem to find a definition anywhere. What would the alternative (i.e. not developmentally programmed) imply?