Active transport
...
In counter-transport two species of
ion or other solute are pumped in opposite directions ... rapid recovery. This shows that a single type of
ion can be transported by several enzymes, which need ... it imports into the cell.
See also
ion channel
...
Chromatography
... (TLC)
5 Gas-liquid chromatography
6
ion exchange chromatography
7 Immobilized metal
ion affinity chromatography
8 High performance ... poor for thermally labile molecules.
ion exchange chromatography ...
Ion gradient
... An
ion gradient is a concentration gradient of ions ... across membranes. Ionophores are important for
ion gradients. The chemiosmotic potential is used ... use them as energy. Several different types of
ion gradients exists in biological systems, the most ...
Electrophysiology
... obviously of value in the study of voltage-gated
ion channels , but also aids in characterizing ... currents in which the activity of many
ion channels is occurring at the same time. However ... to measure the current flowing through a single
ion channel and study its behavior. There are ...
Ion channel
...
ion channels are present in the membranes that ... 6 External links
Basic features
An
ion channel is an integral membrane protein or more ... bees, sea snails and others) work by plugging
ion channel pores. ...
Neurotransmitter
... synapse, the rapid depolarization causes calcium
ion channels to open. Calcium then stimulates the ... receptors. Ionotropic receptors are ligand-gated
ion channels that open or close through neurotransmitter binding. Metabotropic receptor effects on
ion channels are carried by second messenger ...
Signal transduction
... transduction of transmembrane receptors that are
ion channels
3.1.4 Signal transduction of ... proteins in the membrane and open their
ion channels .
Responses
Responses triggered ... AMP (cAMP) and cyclic GMP (cGMP), calcium
ion , phophoinositide derivatives, such as ...
Synapse
... through voltage-dependent, calcium-selective
ion channels , at which point the vesicles fuse with ... molecules and respond by opening nearby
ion channels in the post-synaptic cell membrane, ... or inhibitory depends on what type(s) of
ion channel conduct the post-synaptic current, which ...
Amine
... nitrogen atom has a lone electron pair available which can accept a H +
ion to bond to the nitrogen forming a positive substituted ammonium ion. The ... be formed along with a negative halide ion.
These sort of paired
ion compounds are called quaternary ammonium salts . The X shown in the ...
Dendrite
... without action potentials and without activation of voltage-gated
ion channels . In such dendrites the voltage change that results from ... action potential is mediated by the activation of voltage-gated
ion channels and can interact with synaptic input to alter the synaptic ...
Kidney
... Homeostatic function of the kidney
The kidney regulates the pH, mineral
ion concentration and water composition of the blood.
By exchanging ... in a homeostatic process involving aldosterone which increases sodium
ion absorption in the convoluted tubule.
Any rise or drop in blood osmotic ...
Adenosine triphosphate
... the cell. Also, the hydrolysis yields free inorganic phosphate and adenosine diphosphate , which can be broken down further to another phosphate
ion and adenosine monophosphate . ATP can also be broken down to adenosine monophosphate directly, with the formation of pyrophosphate . This last ...
Alcohol
... upon oxidation, while secondary alcohols give ketones . Tertiary alcohols resist oxidation. Traditionally strong oxidants such as dichromate
ion or potassium permanganate are used, under acidic conditions, for example:
3 CH 3 -CH(-OH)-CH 3 + K 2 Cr 2 O 7 + 4 H 2 SO 4 → ...
Andrew Huxley
... the prize that year with John Carew Eccles , who was cited for research on synapses . Hodgkin and Huxley's findings led the pair to hypothesize
ion channels , which were confirmed only decades later.
The experimental measurements on which the pair based their action potential theory represent ...
ATPase
... a class of enzymes that catalyze the decomposition of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and a free phosphate
ion . This dephosphorylation reaction releases energy , which the enzyme (in most cases) harnesses to drive other chemical reactions that would not ...
Diffusion
... Ions
Diffusion of ions depends on the concentration gradient, and the membrane potential. The net flux of ions can be altered by opening or closing
ion channels.
Diffusion in chemical engineering
Diffusion is the movement of matter due to the movement of the individual molecules (or atoms). ...
Facilitated diffusion
... protein involved is intrinsic, that is, it completely spans the membrane. It also has a binding site for the specific molecule (e.g., glucose ) or
ion to be transported. After binding the molecule, the protein changes shape and carries the molecule across the membrane, where it is released. The ...
Fehling's solution
... copper(II) sulfate pentahydrate
350 grams Rochelle salt (potassium sodium tartrate tetrahydrate) and 100 grams sodium hydroxide
The cupric
ion is complexed with the tartrate ion. Contact with an aldehyde group reduces it to a cuprous ion, which then precipitates as red Cu 2 O ( copper(I) ...
Flagellum
... ) across the bacterial cell membrane due to a concentration gradient set up by the cell's metabolism (in Vibrio species the motor is a sodium
ion pump, rather than a proton pump ). The rotor transports protons across the membrane, and is turned in the process. The rotor by itself can operate ...
Gradient
...
See also
Jacobian
Divergence
Curl
Partial derivation
Vector calculus
Nabla in cylindrical and spherical coordinates
ion gradient
Gradient descent
Level set
...
Hydrolysis
... other contains a carboxylic acid functional group.
The fragment of the parent molecule that was originally a carboxylate gains a hydrogen
ion from the additional water molecule. The fragment that was originally an alkyl group collects the remaining hydroxyl group from the water ...
Lung
... purpose.
Nonrespiratory functions of the lungs
In addition to respiratory functions such as gas exchange and regulation of hydrogen
ion concentration , the lungs also:
influence on the concentration of biologically active substances and drugs used in medicine in arterial blood
...
Microscope
... microscope.
Other types of microscopes
See also microscopy
Atom probe
Atomic force microscope
Electron microscope
Field
ion microscope
Field emission microscope
Phase contrast microscope , see Frits Zernike
Scanning tunneling microscope
Virtual microscope
...
Nicotinamide adenine dinucleotide
... in various organisms as well.
MH 2 + NAD + → NADH + H + + M: + energy, where M is a metabolite.
Two hydrogen ions (a hydride
ion and an H + ion) are transferred from the metabolite. Two electrons are transferred to the positively charged nitrogen, and one hydrogen attaches to ...
Nicotinamide adenine dinucleotide
... in various organisms as well.
MH 2 + NAD + → NADH + H + + M: + energy, where M is a metabolite.
Two hydrogen ions (a hydride
ion and an H + ion) are transferred from the metabolite. Two electrons are transferred to the positively charged nitrogen, and one hydrogen attaches to ...
Nicotinamide adenine dinucleotide
... in various organisms as well.
MH 2 + NAD + → NADH + H + + M: + energy, where M is a metabolite.
Two hydrogen ions (a hydride
ion and an H + ion) are transferred from the metabolite. Two electrons are transferred to the positively charged nitrogen, and one hydrogen attaches to ...
Nephron
... portions of the collecting duct are also permeable to urea , allowing some of it to enter the medulla of the kidney , thus maintaining its high
ion concentration (which is very important for the nephron).
See also
physiology
urology
nephrology
...
Peripheral membrane protein
... binding to integral membrane proteins , or by interactions with the lipid polar head. Therefore the so-called regulatory protein subunits of many
ion channels and transmembrane receptors , for example, may be defined as peripheral membrane proteins. These proteins, in contrast to integral ...
Protein
... proteins. (Certain RNA sequences were shown in the late 20th century to have catalytic properties as well.) Membrane-associated exchangers and
ion channels , which move their substrates from place to place but do not change them; receptors , which do not modify their substrates but may simply ...
Quaternary structure
... and the core is often called the catalytic subunit . Examples of proteins with quaternary structure include hemoglobin , DNA polymerase , and
ion channels . Other assemblies referred to instead as multiprotein complexes also possess quaternary structure. Examples include nucleosomes and ...
Transmembrane receptor
... In certain receptors, 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 ...