Activation energy
... The
activation energy in chemistry is the energy needed by a system to initiate a particular process.
activation energy is often used to denote the minimum energy ... electron clouds repel. This requires energy -
activation energy - and comes from the heat of the system, ...
Allostery
... enhance activity are referred to as allosteric
activation , while the opposite is called allosteric ...
1.2 Sequential model
2 Allosteric
activation
3 Allosteric inhibition
4 Related ... affinity in adjacent subunits
Allosteric
activation
...
Allostery
... enhance activity are referred to as allosteric
activation , while the opposite is called allosteric ...
1.2 Sequential model
2 Allosteric
activation
3 Allosteric inhibition
4 Related ... affinity in adjacent subunits
Allosteric
activation
...
Apoptosis
... in maintaining genomic integrity, and massive
activation of PARP-1 can deplete the cell of ... and intrinsic pathways have in common the
activation of central effectors of apoptosis , a group of ... from mitochondria (see below), and the amplified
activation of caspase-8.
Downstream from TNF-R1 and ...
Immune system
... destruction of the pathogen by formation and
activation of the membrane attack complex , and ... After they leave the thymus, T cells require
activation to proliferate and differentiate into "killer" T cells (CTLs).
activation is provided by antigen presenting cells (APCs). A ...
Oncogene
...
1 Protooncogene
1.1
activation
2 Oncogene
2.1 Growth factors
... usually through its protein product. Upon
activation , it (or its product) becomes a tumor inducing agent, an oncogene.
activation
The protooncogene can become an oncogene by a ...
Signal transduction
...
5.1 Ca2+ as a second messenger
5.1.1
activation of Ca2+
5.1.2 Function of Ca2+
5.2 ... triggered by signal transduction include the
activation of a gene , the production of metabolic energy ... remodelling of the cell skeleton .
Gene
activation leads to further effects, since genes are ...
B cell
... antibodies that circulate in blood plasma and lymph ) involves B cell
activation . Cell
activation can be gauged using the ELISPOT technique, which can determine the ...
Dendrite
... convey stimulation passively, without action potentials and without
activation of voltage-gated ion channels . In such dendrites the voltage change ... in most neurons. This backpropagating action potential is mediated by the
activation of voltage-gated ion channels and can interact with synaptic input to ...
Enzyme
... catalyzed substrates. Like any catalyst, enzymes work by lowering the
activation energy of a reaction, thus allowing the reaction to proceed to its steady ... rate by favoring or enabling a different reaction pathway with a lower
activation energy , making it easier for the reaction to occur. The overall rate of ...
Ion channel
...
1 Basic features
2 Biological role
2.1 Diversity and
activation
3 Detailed structure
4 History
5 See also
6 ... for any drug, ion channels are a favorite target.
Diversity and
activation
Voltage-gated channels sense the transmembrane potential and ...
Major histocompatibility complex
... appropriately ignore. A full-force immune response usually requires the
activation of B cells via BCRs and T cells via the Mhc -TCR interaction. This ... of phagocytes or may lead to a full-force antibody immune response due to
activation of B cells.
MHC evolution and allelic diversity
MHC gene families ...
Nervous system
... , such as sea anemones and jellyfish , have a nerve net , in which the
activation of any one neuron triggers a wave of
activation across the entire network. These waves are both afferent and efferent , ...
Antibody
... developed. It can bind to many kinds of pathogens, for example viruses , bacteria , and fungi and protects the body against them by complement
activation (classic pathway), opsonization for phagocytosis and neutralisation (immunology) of their toxins. There are 4 subclasses: IgG1 (66%), IgG2 (23%), ...
Biomechanics
... on the biochemical reaction, where C a 2 + and ATP move the troponin and tropomyosin to allow for the crossbridges to bind to the
activation sites on the actin.
It has been shown that applied loads and deformations can affect the properties of living tissue. There is much research in the ...
Chromatography
... with a small amount of inert binder like calcium sulfate (gypsum) and water, spreading the a thick slurry on the carrier, drying the plate, and
activation of the adsorbent by heating in an oven.
The thickness of the adsorbent layer is typically around 0.1 - 0.25 mm for analytical purposes and around 1 ...
Diabetes mellitus
... or poor timing of either. If blood glucose levels are low enough, the patient may become agitated, sweaty, and have many symptoms of sympathetic
activation of the autonomic nervous system - they may experience feelings similar to dread and immobilized panic. Consciousness can be altered, or even lost, in ...
Hormone
... Hormone actions vary widely, but can include stimulation or inhibition of growth, induction or suppression of apoptosis (programmed cell death),
activation or inhibition of the immune system , regulating metabolism and preparation for a new activity (e.g. fighting, fleeing, mating) or phase of life ....
Insulin
... In a few cases, there is a defect in the release of insulin from the pancreas. Either way, the effect is the same: elevated blood glucose levels.
activation of insulin receptors leads to internal cellular mechanisms which directly affect glucose uptake by regulating the number and operation of protein ...
Memory
... however, argue that the distinction between long- and short-term memories is arbitrary, and is merely a reflection of differing levels of
activation within a single store.
If we are given a random seven-digit number, we may remember it only for a few seconds and then forget (short-term memory). ...
Origin of life
... common ancestor
Zeolites
References
PMID 11882894
(Cited on p. 108).
Huber, C. and Wchterhuser, G., (1998) "Peptides by
activation of amino acids with CO on (Ni,Fe)S surfaces: implications for the origin of life". Science 281 , 670–672. (Cited on p. 108).
Brooks, J. ...
Parthenogenesis
... sperm in order to develop. However, the sperm cell does not contribute any genetic material to the offspring. Since gynogenetic species lack males,
activation of the egg requires mating with males of a cloesly related species. Some salamanders of the genus Ambystoma are gynogenetic and appear to have ...
Transmembrane receptor
... such as the nicotinic acetylcholine receptor , the transmembrane domain forms a protein-lined pore through the membrane, or ion channel . Upon
activation of an extracellular domain by binding of the appropriate ligand, the pore becomes accessible to ions, which then pass through. In other receptors, ...