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Å: See Angstrom unit.
aK: As used in this volume, aK represents the
activity of the potassium ion, K+. As such, it is equal to the product of the concentration of the ion (СK) and its activity coefficient (γK).
A-band: optically dense band in a striated muscle fiber (see Figs. 15, 16)
absorb: to take up (like a sponge)
α-amino group: an amino group (NH2) when
attached to an α-carbon atom (immediately adjacent to a functional group) Example: the amino group of the amino acid glycine
(NH2CH2COOH) is an α-amino group.
α-helical conformation: the principal secondary structure of most globular proteins. In this conformation each amide group is attached by a H-bond to the third one from it in either direction along the polypeptide chain.
α-helical potential: the empirically determined propensity or potential of a specific type of amino acid residue to engage in an
α-helical structure
α74asp-α75asp: a nearest neighboring pair of aspartic-acid residues located respectively at position 74 and 75 on the a-chains of a hemoglobin molecule
abscissa: the horizontal axis. See ordinate.
absolute temperature: the temperature of the Kelvin scale, which has its zero at -273.16°
C It is a temperature at which a gas would show no pressure, if the general gas law held for all temperatures. It has degree units of the same magnitude as the centigrade scale and represented as
oK.
acetic acid: СН3СООН, a weak acid found in vinegar.
acetylphenoneoxime: an organic chemical having a structure shown in the inset of Fig. 47.
acid dissociation constant: the equilibrium constant for the dissociation of a specific kind of acid. Thus for acetic acid, the acid
dissociation constant (represented as K) is equal to the product of the concentration of the
H+ ion multiplied by the concentration of the acetate ion and divided by the concentration of the unionized acetic acid at the equilibrium condition. K for acetic acid is 1.76 x
10-5. The negative logarithm of K is called pK. The pK of acetic acid is thus 4.76.
acronym: a word formed from the initial letter(s) of successive parts of a compound term.
actin: the major protein component of the thin filaments of striated muscle and of
microfilaments in many cell types.
action potential: the transient local electrical potential variation, which causes an active
locus to be electrically negative to the quiescent region of the nerve or muscle surface. It is the physical basis of the nerve or muscle impulse.
active living state: the state of a living cell or protoplasm when it is "in activity".
active transport: movement of ions or molecules against a concentration and/or electrical
gradient by a mechanism that requires the expenditure of energy
activity: The attributes of ions or molecules as a component in a solution may be weakened due to interaction with other components of the system so that they appear as if they are lower in concentration than they actually are—by a fractional number, f, called the
activity coefficient. The activity of the component is the product of the concentration (C) and the activity coefficient and often
represented by the letter a.
activity coefficient: A factor introduced by G.N. Lewis to correct for other-than-ideal
behavior of substances in solution. An activity coefficient of 0.8 for a sodium ion, for ex-ample, means that in that specific
environment, the sodium ion is or does only 80% of what a sodium ion in an ideal environment is or does.
actomyosin gel: a gel formed from a complex of the two muscle proteins, actin and myosin.
ad infinitum: (Latin) without end.
adenosine diphosphate (ADP): the major hydrolytic product of ATP when acted upon by, for example, an enzyme called ATPase.
adenosine triphosphate (ATP): a critically important nucleotide compound found in virtually all living cells It is the end-product of the living cell's energy metabolism.
ADP: See adenosine diphosphate.
adrenaline: also known as epinephrine It is a hormone produced by the adrenal glands and has wide-spread physiological effects on tissues innervated by the sympathetic nerves.
adsorb: to take up on the surface of a solid or on specific sites of a solid or macromolecule.
adsorbent: the substance that is adsorbed.
adsorption: the occurrence of high concentration of any substance at the surface of a solid or liquid (For more details and history, see Ref. 107,
p.37, n5.) (See also close-contact adsorption and localized adsorption).
adsorption constant: an equilibrium constant for the (close contact) adsorption of a substance on a fixed site and usually given in units of reciprocal moles. Example: the adsorption constant of ATP on the major muscle
protein myosin is 1010 to 1011 M-1.
adsorption isotherm: a line on a chart or an equation describing the relationship between the pressure (concentration) of a gas (solute) and the amount of gas (solute) adsorbed at a constant temperature.
adsorption site: a specific locus on a solid surface or a macromolecule, which has the potential of adsorbing an ion or molecule.
adsorption-desorption route: one of the two major modes of entry or exit of an ion or
molecule into or from a fixed charge-carrying system like the surface of a muscle cell This mode of entry or exit involves the
adsorption of the ion or molecule from one side of a fixed site at the cell surface and its
subsequent emergence on the other side of the cell surface.
"adsorption-staining method": a special technique introduced in 1991 by Ludwig
Edelmann,282 which makes visible and thus identifiable special anionic loci in ultra-thin electron microscopic sections by exposing the thin sections of the frozen tissue to electron-dense ions like
Cs+ in the presence of Li+.
"affinity": attraction often in a highly specific manner.
AgNO3: silver nitrate, water-soluble, colorless crystals.
AIH, AI Hypothesis: acronyms of the association-induction hypothesis.
alanine: one of the common α-amino acids found in most proteins.
alkali-metal ions: members of the group of univalent basic metals belonging to the first group of the periodic table. Highly reactive, they readily give off one electron becoming univalent alkali-metal ions. Examples:
Li+, Na+, K+, Rb+, Cs+.
alkalinity: having properties of an alkali, exhibiting a pH higher than 7.0.
all-or-none: marked by either exhibiting full effect or none at all.
alteration theory: a theory of the origin of what was then measured between the cut end and intact surface of a nerve or muscle and known as
injury potential (or demarcation potential). According to this alteration
theory, the electric potential difference measured as injury potential exists only at the site of injury (or activity). Its chief advocate was Ludimar Hermann (1838-1914), Emil DuBois-Reymond's student.
amino acid: any one of a group of some twenty organic compounds containing an amino group and a carboxyl group. Amino acids make up proteins.
amino-acid sequence: the linear sequential order of arrangement of various amino acid residues in a polypeptide or protein.
amino group: --NH2 or in its ionized form, --NH3+.
ammonium sulfide: (NH4)2S, water-soluble
crystals at below 0° C but decomposing at higher temperatures.
amphiuma: an amphibian inhabiting Southern United States It has a snake-like body and four small limbs.
Amphotericin B: also known as Fungizone, an antifungal antibiotic produced by
Streptomycetes culture.
amyl alcohol: one or a mixture of various saturated aliphatic alcohols containing 5 carbon atoms.
anaerobic: living, be active or occurs in the absence of free oxygen.
Angstrom unit: a unit of length equal to 10-8
centimeter, named after 19th century Swedish physicist, A. J. Ångstrom.
animalcules: antiquated name for tiny animals.
anion: a negatively-charged ion. The name (as well as those of ion, cations and other related subjects) was introduced by philologist, Rev. William Whewell of Trinity College in response to the request of Michael Faraday to designate the charge-bearing particles (in an electrolyte solution) that migrate to the positively-charged electrode or anode.
antiferromagnetic cooperative transition: a cooperative transition, which shows unfavorable or negative near-neighbor interaction energy, i.e.,
-γ/2 << 0, in the terminology used in this volume.
antiferromagnetism: A number of ferromagnetic substances contain two interlocking types of atoms or atom groupings, referred to as sublattices, which tend to magnetize
oppositely. Such substances tend to show a cancellation of the total magnetization. This phenomenon is referred to as
antiferromagnetisim.
antiparallel orientation: orientation of individual polar elements that is opposite to that of parallel orientation.
apparent equilibrium distribution coefficient (ρ-value): After diffusion equilibrium has been reached, the ratio of the concentration of a substance in the water within a living cell or model system over that in the surrounding medium is called the (true)
equilibrium distribution coefficient (or q-value), if the substance present in the cell and in the surrounding medium are all in a free state. In the case where an adsorbed or otherwise non-free form of the substance also coexists with the substance in the cell water in a free state, the (unresolved) equilibrium
distribution coefficient is then referred to as an apparent equilibrium distribution coefficient or p-value. Note that the
ρ-value may be equal to, or larger than the true equilibrium distribution coefficient or q-value but never smaller than the q-value.
arginine: a common α-amino acid found in most proteins It carries an additional positively-charged guanidyl group beyond the
α-amino group (and α-carboxyl group) shared by all α-amino acids. Like lysine, its presence in a protein endows the protein with a positively charged guanidyl side chain.
arginine residue: when an arginine participates in the formation of a polypeptide or protein, it becomes an arginine residue in the polypeptide or protein.
Arrhenius's theory of ionic dissociation: In 1887, S. A. Arrhenius, Swedish physico-chemist (1859-1927) proposed the theory that in a water solution, a substantial portion of acids, salts and bases dissociate
spontaneously into positive and negative ions, which are then free to move around
independently.
association-induction hypothesis: In 1962 G. N. Ling introduced the first physico-chemical theory of life at the molecular and electronic level. In this hypothesis the three major components of the living cells, proteins,
water and ions are largely associated and electronic polarization or induction provides the basic mechanism for the coordination and coherence of functional activities.
atomic weight: the relative weight of the atom on the basis of oxygen as 16 rounded off to the nearest integer. The atomic weight of a pure isotope gives the number of neutrons and protons in the atom's nucleus.
ATP: See adenosine triphosphate.
ATPase: an enzyme, which hydrolyzes ATP into ADP and inorganic phosphate.
aurovertin: an antibiotic, which strongly inhibits mitochondrial oxidative phosphorylation and first introduced by H. Lardy to investigate mitochondrial functions.
autocooperative adsorption: A type of adsorption, in which the adsorption of an ith
adsorbent on one site enhances the affinity of the two nearest-neighboring sites for the ith adsorbent. In other words, a type of
adsorption, which shows positive nearest-neighbor interaction, i.e., -γ/2 <<
0.
autocooperative interaction: interaction in which a primary event favors subsequent events of similar nature.
autocooperative transition: a cooperative transition that is abrupt and "all or none" as a
result of the strongly positive nearest-neighbor-interaction energy in the assembly.
autocooperativity: being, or in possession of the trait exhibited by an assembly showing auto-cooperative attributes in consequence of the possession of strongly positive nearest-neighbor-interaction energy.
autoradiography: the science and technique of localizing a chemical substance, X, in living cells and tissues by introducing into the cell or tissue a radioactively labeled substance X
and after air-drying, freeze-drying or other technique to remove the water in the sample, covering the sample with a thin film of photo emulsion in the dark After due expo-sure and development, the silver granules visualized point to the locations of substance X in the living cell or tissue.
auxiliary cardinal adsorbent: a cardinal adsorbent, which functions as a modifier of the
living state Its action is, as a rule, superposed on that of the principal cardinal adsorbent, ATP, which plays the primary role of
maintaining the living state.
Avogadro number: The number of individual atoms in a gram atom, of ions in a gram ion, or of molecules in a mole is called the
Avogadro number and equal to 2.02 x 1023.
Avogadro's Law: Equal volumes of all gases, under the same conditions of temperature and pressure, contain equal numbers of
molecules.
axon: a nerve fiber, the long process extending from and continuous with the cell body of a nerve.
axoplasm: the gel-like protoplasm making up the bulk of nerve axons.
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