Allostery
... are connected in such a way that a conformational
change in one subunit is necessarily conferred to all ... not connected in such a way that a conformational
change in one induces a similar
change in the others. Thus all enzyme subunits need not ...
Allostery
... are connected in such a way that a conformational
change in one subunit is necessarily conferred to all ... not connected in such a way that a conformational
change in one induces a similar
change in the others. Thus all enzyme subunits need not ...
ATP synthase
... showTocToggle("show","hide")
1 Binding
change mechanism
2 Physiological role
3 Plant ... See also
7 External links
Binding
change mechanism
In the 1960s through the 1970s, Paul ... ATP synthesis is coupled with a conformational
change in the ATP synthase generated by rotation of the ...
Biology
... descent of life
1.5 Homeostasis: adapting to
change
1.6 Interactions: groups and environments
... domain system ).
Homeostasis: adapting to
change
Main article: Homeostasis
Homeostasis is ... origin and descent of species , as well as their
change over time, i.e. their evolution .
Evolutionary ...
Culture
... of products and activities
2 Cultural
change
3 Cultural studies
4 List of cultures ... it a potentially rapid form of adaptation to
change in physical conditions. Anthropologists view ... although bounded, would change. Cultural
change could be the result of invention and ...
Eugenics
... endeavor, and hoped that if social mores could
change so that people could see the importance of ... claimed that new policies were needed to actively
change the status quo towards a more "eugenic" state, ... founder of 1950s marriage counseling , a career
change which initially grew out of his eugenic interests ...
Evolution
...
Generally, evolution is any process of
change over time. In the context of life science , evolution is a
change in the traits of living organisms over ... evolution has been defined more specifically as a
change in the frequency of alleles in a population ...
Homeostasis
... and social systems are homeostatic. They oppose
change to maintain equilibrium. If the system does not ... feedback
Main article: Feedback
When a
change of variable occurs, there are two main types of ... feedback , the response is to amplify the
change in the variable. This has a de-stabilizing ...
Punctuated equilibrium
... and the perhaps typical lack of substantial
change of species during their existence.
... with Darwinism
The lack of substantial gradual
change of perhaps most species in the geologic record, ... assumed that he insisted that the rate of
change be constant or nearly so. Punctuation appears ...
Signal transduction
... Signal transduction of transmembrane receptors on
change of transmembrane potential
3.2 Nuclear ... and trigger events inside. This takes place via a
change in the shape or conformation of the receptor ... its ligand, and then undergo a structural
change that opens a gap (channel) in the plasma membrane ...
Species
... regions. The dividing line is often a sudden
change in habitat (an ecotone ) like the edge of a ... most naturalists understood that species could
change form over time, and that the history of the ... emphasis was on determining how a species could
change over time. Lamarck suggested that an organism ...
Botany
... past climates and predict future ones, an essential part of climate
change research.
Recording and analysing the timing of plant life cycles is an important part of phenology used in climate
change research.
Lichens , which are sensitive to atmospheric conditions, have ...
Diabetes mellitus
... Patient understanding and participation is vital as blood glucose levels
change continuously, while successfully keeping blood sugar within normal ... the United States alone. The Centers for Disease Control has termed the
change an epidemic . The National Diabetes Information Clearinghouse estimates ...
Enzyme
... As with any catalyst, an enzymatic pathway does not intrinsically
change the reversibility or irreversibility of a reaction. The direction of any ... the two sides of the reaction equation, and if there is very little
change in net free energy between the substrates and the products, the reaction ...
Equilibrium
... proceeds at the same rate as its reverse reaction, resulting in no net
change in the amount of each compound .
Mechanical equilibrium , also known ... , the state of a system in which its internal processes cause no net
change in its macroscopic properties (such as temperature and pressure).
In ...
Genetic drift
... mechanism of evolution that acts in concert with natural selection to
change the characteristics of species over time. It is a stochastic effect ... population. Subsequent to the latter event, the allele frequency can only
change by the introduction of a new allele by a new mutation .
The lifetime of ...
Gradient
... is a
vector field which points in the direction of the greatest rate
of
change of the scalar field, and whose magnitude is the greatest rate of
change.
... is φ( x , y , z ) . We
will assume that the temperature does not
change in time. Then, at
each point in the room, the gradient at that point will ...
Molecular evolution
... 2 Principles of molecular evolution
2.1 Mutations
2.2 Causes of
change in allele frequency
2.3 Molecular study of phylogeny
2.4 The neutral ... ; the modern interpretation of classic evolutionary theory.
Causes of
change in allele frequency
Main article: Population genetics
There are ...
Neutral theory of molecular evolution
... assertion or hypothesis of the neutral theory is that most evolutionary
change is the result of genetic drift acting on neutral alleles . A new allele ... 0-521-23109-4
Richard Lewontin The Genetic Basis of Evolutionary
change Columbia University Press, 1974 ISBN 0-231-03392-3
External links ...
Population genetics
... Population genetics is the study of the distribution of and
change in allele frequencies under the influence of the four evolutionary ...
Richard C. Lewontin. 1974. The Genetic Basis of Evolutionary
change . Columbia University Press. New York.
External links
History ...
Protein
... channels , which move their substrates from place to place but do not
change them; receptors , which do not modify their substrates but may simply ... represents one of the chief tools of cell and molecular biologists to
change and to probe the workings of cells. Another area of protein research ...
Absorption spectrum
... passing through a sample of cold gas. For any collection of atoms or molecules , there are certain specific amounts of energy required to
change state; for individual atoms, these correspond to an electron moving from one orbit (energy level) to another. An electron can jump to a higher ...
Active site
... by the enzyme. In noncompetitive inhibition , the inhibitor binds to the enzyme at another site, the allosteric site , and this causes a structural
change in the enzyme such that the active site is rendered useless. Uncompetitive inhibition , is similar to noncompetitive inhibition except that the ...
Adaptive radiation
... species that cover the new ecological niches created by the environmental change. An example of adaptive radiation as the result of an environmental
change is the rapid spread and development of mammalian species after the extinction of the dinosaurs.
Archipelagoes . Isolated ecosystems , such ...
Alternative splicing
... in a DNA sequence whose length would only be enough for two proteins in the prokaryote way of coding.
Others have noted that it is unnecessary to
change the DNA of a gene for the evolution of a new protein. Instead, a new way of regulation could lead to the same effect, but leaving the code for the ...
Ames test
... , generally genetic toxicology , to test for mutagenic properties of a chemical compound. A compound is said to be mutagenic if it causes a
change in the DNA (deoxyriboneucleic acid) of a living cell or organism. The test is named after its inventor, Bruce Ames .
General procedure
...
Biodiversity
... Just like a species with high genetic diversity , an ecosystem with high biodiversity may have a greater chance of adapting to environmental
change . In other words, the more species comprising an ecosystem , the more stable the ecosystem is likley to be. The mechanisms underlying these effects ...
Bacterium
... of sexual reproduction, genetic variations can occur within individual cells through recombinant events such as mutation (random genetic
change within a cell's own genetic code).
Similar to more complex organisms, bacteria also have mechanisms for exchanging genetic material. Although not ...
Bioinformatics
... sequence motif .
Computational evolutionary biology
Evolutionary biology is the study of the origin and descent of species, as well as their
change over time. Recent developments in genome sequencing and the ubiquity of fast computers enable researchers to trace evolution of species by tracing ...
Biological tissue
... together. Blood is considered a connective tissue.
Muscle tissue - Muscle cells contain contractile filaments that move past each other and
change the size of the cell.
Nervous tissue - cells forming the brain , spinal cord and peripheral nervous system
Examples of tissue in ...
Bone
... bones of the skull, the ribs, the vertebrae and pelvic bones.
Remodeling is the process of resorption followed by replacement of bone with little
change in shape and occurs throughout a person's life. Its purpose is the release of calcium and the repair of micro-damaged bones (from everyday stress). ...
Crassulacean acid metabolism
... into pits. Some xerophytes shed their leaves during the driest seasons and others can store water such as cacti. CAM plants uptake CO2 at night and
change it into crassulacean acid that can be broken down during the day for sugars. These plants can close their stomata during the day.
These plants ...
Crassulacean acid metabolism
... into pits. Some xerophytes shed their leaves during the driest seasons and others can store water such as cacti. CAM plants uptake CO2 at night and
change it into crassulacean acid that can be broken down during the day for sugars. These plants can close their stomata during the day.
These plants ...
Cancer
... cells are selected to build them. This process is called clonal evolution . A first step in the development of a tumor cell is usually a small
change in the DNA, often a point mutation , which leads, among other things, to a genetic instability of the cell. The instability increases to a point ...
Charles Darwin
... Lyell .
He discovered fossils of gigantic extinct South American Megatheriums and Armadillos in strata which showed no signs of catastrophy or
change in climate, and found later that these were relatives of creatures still living in the area.
Argentinian Rheas , and mockingbirds on ...
Chlorophyll
... hours. (Variegated leaves have green areas that contain chlorophyll and white areas that have none.) When tested with iodine solution , a color
change revealing the presence of starch occurs only in regions of the leaf that were green and therefore contained chlorophyll. This shows that ...
Chromatography
... K is based on this equilibrium, and is defined by the following equation:
K is assumed to be independent of concentration, and can
change if experimental conditions are changed, for example temperature is increased or decreased. As K increases, it takes longer for solutes to ...
Bioinformatics
... sequence motif .
Computational evolutionary biology
Evolutionary biology is the study of the origin and descent of species, as well as their
change over time. Recent developments in genome sequencing and the ubiquity of fast computers enable researchers to trace evolution of species by tracing ...
Denaturation
...
Denaturation in Biochemistry refers to a structural
change in macromolecules caused by extreme conditions.
Denaturation can refer to the intentional adulteration of ethyl alcohol so that it is ...
Dendrite
... convey stimulation passively, without action potentials and without activation of voltage-gated ion channels . In such dendrites the voltage
change that results from stimulation at a synapse may extend both towards and away from the soma. In other dendrites, voltage-gated channels help propagate ...