Equilibrium
... For the 2002 science fiction movie see
equilibrium (2002 movie)
equilibrium or balance is any of a number of related ... In general, a system is said to be in a state of
equilibrium if all influences on the system are cancelled by ...
Evolution
... might result in what is known as punctuated
equilibrium , the modern interpretation of classic ... underpinning of the theory of punctuated
equilibrium .
Extinction is the disappearance of species ... debates is over the theory of punctuated
equilibrium , a theory propounded by Niles Eldredge and ...
Hardy-Weinberg principle
... principle ( HWP ) (also Hardy–Weinberg
equilibrium ( HWE ), or Hardy–Weinberg law ) states ... gene locus will become fixed at a particular
equilibrium value. It also specifies that those
equilibrium frequencies can be represented as a simple ...
Punctuated equilibrium
... Punctuated
equilibrium , or punctuated equilibria , is a theory of ... Gould's advocacy of the theory brought punctuated
equilibrium much attention, especially since they phrased it ... evolutionary biologists wryly termed punctuated
equilibrium "evolution by jerks." (It is now sometimes ...
Alcohol
... in pK a to many alcohols, so with sodium hydroxide there is an
equilibrium set up which usually lies to the left:
R-OH + NaOH R-O - Na + ... :
R-OH + R'-COOH R'-COOR + H 2 O
In order to drive the
equilibrium to the right and produce a good yield of ester, water is usually ...
Allostery
... holds that in the absence of any ligand (substrate or otherwise), the
equilibrium favors the T state over the R state. To summarize:
all subunits must exist in the same conformation
equilibrium favors the T state over the R state
The binding of substrate to one ...
Allostery
... holds that in the absence of any ligand (substrate or otherwise), the
equilibrium favors the T state over the R state. To summarize:
all subunits must exist in the same conformation
equilibrium favors the T state over the R state
The binding of substrate to one ...
Apoptosis
... (cell proliferation) in the tissue is balanced by cell death. If this
equilibrium is disturbed, either of two things happen:
The cells are dividing ... Morphology, above) were present in cells that died in order to maintain an
equilibrium between cell proliferation and death in a particular tissue (see ...
Homeostasis
... so as to maintain a stable condition, by means of multiple dynamic
equilibrium adjustments controlled by interrelated regulation mechanisms.
The term ... , internal, structural, and functional, contributes to the maintenance of
equilibrium
They are unpredictable (the resulting effect of a precise action often ...
Molecular evolution
... accumulate over time, which might result in what is known as punctuated
equilibrium ; the modern interpretation of classic evolutionary theory.
Causes of ... of load known as segregational load . Crow and Kimura showed that at
equilibrium conditions, for a given strength of selection ( s ), that there would be ...
Allele frequency
... randomly only in the absence of selection and under other assumptions. When these conditions apply, a population is said to be in Hardy-Weinberg
equilibrium .
The frequencies of all the alleles of a given gene often are graphed together as an allele frequency distribution histogram . Population ...
Biology
... is the property of an open system to regulate its internal environment so as to maintain a stable condition, by means of multiple dynamic
equilibrium adjustments controlled by interrelated regulation mechanisms. All living organisms , whether unicellular or multicellular exhibit ....
Biomechanics
... often modeled using spatial or Eulerian coordinates. Using these postulates and some assumptions regarding the particular problem at hand, a set of
equilibrium equations can be established. The kinematics and constitutive relations are also needed to model a continuum.
Second and fourth order tensors are ...
Carbohydrate
... bridge between the two carbon atoms, forming a heterocyclic ring. Rings with five and six atoms are called furanose and pyranose forms, and exist in
equilibrium with the straight-chain form.
It should be noted that the ring form has one more optically active carbon than the straight-chain form, and so has ...
Chromatography
... do depend on the solvent used, and the type of TLC plate.
Gas-liquid chromatography
Gas-liquid chromatography is based on a partition
equilibrium of analyte between a liquid stationary phase and a mobile gas. It is useful for a wide range of non-polar analytes, but poor for thermally labile ...
Ewens's sampling formula
... The assumptions are (1) the sample size n is small by comparison to the size of the whole population, and (2) the population is in statistical
equilibrium under mutation and genetic drift and the role of selection at the locus in question is negligible, and (3) every mutant allele is novel.
This ...
Extinction
... : Patterns of Life and the Future of Humankind by Richard Leakey ( ISBN 0385468091 ).
Mass extinctions are a key part of the punctuated
equilibrium hypothesis of Stephen Jay Gould and Niles Eldredge . See: Time Frames: The Evolution of Punctuated Equilibria ( ISBN 0691024359 )
Human ...
Glucose
... with the exception of the fifth atom, which links to a 6th carbon atom outside the ring, forming a CH 2 OH group. This ring structure exists in
equilibrium with a more reactive acyclic form, which makes up 0.0026% at pH 7.
Glucose is a ubiquitous fuel in biology . We can speculate on the reasons why ...
Hydrolysis
... for each water molecule produced. As hydrolysis is a reversible reaction, condensation and hydrolysis can take place at the same time the position of
equilibrium determining the amount of each product.
Irreversibility of hydrolysis under physiological conditions
Under physiological conditions (i.e. in ...
Metapopulation
... of occupied patches, dN , is
d N = (1 - N ) c N - e N .
This takes on a sigmoid shape similar to the logistic model . The
equilibrium value of N can be calculated by setting dN to be equal to zero. Solving for N gives either N = 0 or
N = 1 - e / c
This ...
Photon
... states , describing coherent light such as emitted by an ideal laser ) or mixtures (so-called thermal states ), describing light in thermal
equilibrium ( black-body radiation ).
The associated quantum state is the Fock state denoted , meaning n photons in the electromagnetic field mode ...
Potential energy
... by:
where k is the spring constant (a measure of the stiffness of the spring), expressed in N/m, and x is the displacement from the
equilibrium position, expressed in metres (see Main Article: Elastic potential energy ) .
Chemical energy
Chemical energy is a form of potential energy ...
Proprioception
... that is often used interchangeably with proprioception. Some users differentiate the kinesthetic sense from proprioception by excluding the sense of
equilibrium or balance from kinethesia. An inner ear infection, for example, might impact the sense of balance. This would impact the proprioceptive sense, ...
Speciation
... usually remain unchanged over long stretches of time, and that speciation occurs only over relatively brief intervals, a view known as punctuated
equilibrium . It is entirely possible that speciation has occurred by several mechanisms simultaneously over evolutionary history.
...