330 



INDEX 



per mole; nonbonding orbital; neutron; 

 order of diffracted radiation; number of 

 moles 



_/V — a number, used generally as a depend- 

 ent variable; number of radioactive 

 atoms; number of impinging particles 



yV — a reference state for .\ 



Nachmansohn, on biochemistry of nerve 

 conduction, 271 

 on ACE, 276 

 n — 7r transition, electronic transition from 

 nonbonding orbital to a 7r-orbital, il- 

 lustration and energy of, 147 

 molecules which can undergo the, 147 

 mutations resulting from the, 146 

 Nernst equation, 180 



and hydrogen electrode, 181-182 

 in concentration cells, 267 

 method of derivation from thermody- 

 namic principles, 180 



Neutrino, 73, 106 

 Nerve, action potentials of, 262 ff 

 axons, 264 ff 

 change in structure in phenylketonuria, 



159 

 electrolytic conduction of, 265, 306 

 propagation velocity of, 265 

 Nerve impulse, as a transient bioelectric, 

 262, 265 

 digital nature of, 263 

 shape of spike, 265, 306 

 Nerve propagation, concentration changes 

 during, 267 

 experiments on, 266 ff 

 permeability changes during, 271 

 theory of, 269 ff 

 tracers in the study of, 266 

 Neural networks, simulation of properties 



by computers, 304-305 

 Neuron, illustrations of, 264, 291 

 in central nervous system, 274 

 propagation along axon of, 262-265, 269- 

 271 

 Neurosonic surgery and therapy, 72-73 



Dunn-Fry law, time to paralysis vs intens- 

 ity, 64 

 Neutron activation, for analysis, 1 19 



Neutrons: 



in nucleus, 82 



ionization by, 105 



nature and physical properties, 103, 

 106-107 



penetration by, 1 18 

 Newton, law of cooling, 227 



laws of motion, 27 



Nirenburg, Ochoa, et al., on coding in 



nucleic acids, 154 ff 

 Noise, and absolute threshold of hearing, 55 



and control, 296 



from several sources in man's environ- 

 ment, 60 



in the computer, and control, 309 



influence on information, 315 



subjective character of, in man, 299, 31 5 

 Nonpolarizable reversible electrodes, 274 

 Nucleic acids (See DNA and RNA) 



structure of, 149, 150 

 Nucleus of an atom, 73-74, 103-104 



properties and stability, 103 

 Nucleus of a cell, 264 



— zero 



" — degree sign (° C, ° F and ° K: degrees 

 Centigrade, Fahrenheit, and Kelvin, 

 respectively) 

 Ohm's law, 40, 219 



Optics (See Eye, Color vision. Light, etc.) 

 Orbitals, atomic and molecular, 74-75 



electron migration and energy transfer 

 along 7T-, 74, 145-147,271 

 Order, of differential equation, 16 



of reaction, 195-196, 311 

 Organization, and definition of life, 75 



from subatomic to superorganismic, 315 

 Osmosis, as a special case of diffusion, 

 36, 212 

 driving force for, 36 

 in living systems; water balance, 37 

 through red blood cell wall, 142 

 Osmotic pressure, as a thermodynamic 

 property, 36 

 and water balance, 37 

 and restoring pressure in cell walls, 37-38 

 and molecular weight of macromolecules, 



136 

 cell plasma composition and, 38 

 Otoconiae, 99 

 Otology, 57 

 Oxidation-reduction reactions (See Redox 



systems) 

 Oxygen effect in radiation sensitivity and 

 radiology, 244 



p — distance from image to lens; proton 



P — pressure; number of points, or even a 



single point; power or energy flux, 283 

 /' M — power expended as work, 283 

 I\y t — power expended as heat, 283 

 (P — permeability constant 

 Pacemaker of heart, 273 



