234 



INDEX 



Mitochondria, 39 

 Model of catalysis, 192 



- of circulation, 218 

 Mol, 19 



Molar concentration of proteins, 143 



- solutions, 19 

 Molecular concentration, 19 

 Molecules, 4 



Motor areas, 129 



- centre, 120 

 Movements, 93 



- of alimentary canal, 78 

 Muscle system, nature of, 95 

 Muscles, 79 



Muscular sense, 119 



- work and loss of structure, 40, 62 

 Mutual aid, 58, 159 



- precipitation of colloids, 179 

 Myograph, 205 



NATURAL selection, 158 

 Nature of muscle system, 95 



- of nerve impulse, 130, 131 

 Negative after-image, 116 



- temperature coefficient of muscle, 

 96 



Nerve, electrical change in, 210 



- impulse, 130 



- structure of, 209 



- unexcited by sound or light, 210 

 Nerve-cell, 121 



Nerve-muscle preparation, 204 

 Nerves, 104 

 Neurone, 121 



- structure of, 216 

 Neutral red, 27 

 Neutrality of blood, 142 



- regulation by kidney, 144 

 Newt's gastric glands, 197 

 Nitrates as plant food, 57 



- formed in soil, 186 

 Nitrogen, source of, 45 



- test for, 181 

 Nitrogen-cycle, 56, 77 

 Nitrogen-fixing organisms, 58 

 Nocuous stimuli, 106 

 Non-polarisable electrodes, 197 

 Nuclear division, 152 

 Nucleus, 3, 39, 42, 121 



OCEAN, composition of, 60 

 Oedema, 140 

 Oesophagus, 71 



Oils, 65 

 Olein, 65 



Olfactory cells, 211 

 Olive oil, 65 

 Optical activity, 48 



- isomers, 48, 49 



- sensitizer, 52 

 Organ of Corti, 108, 109 

 Organic compounds, 41 

 Origin of heart beat, 150 

 Osmometer, 171 

 Osmosis, 17 



Osmotic pressure, 21, 169 

 Ova, 153, 226 

 Ovary, 153 

 Oxidase, 91 



- of potato, 203 

 Oxidation, mechanism of, 89 

 Oxidising enzymes, 76 



Oxygen consumption and work, 100 



- test for, 181 

 Oxy-haemoglobin, 87 



PACE-MAKER of the heart, 225 



Pain, 104, 1 06 



Pancreas, granules in, 196 



Pancreatic juice, 71, 74, 75 



Paralysis, 80 



Parthenogenesis, 153 



Partial pressure, 85 



Penis, 154 



Pentoses, 42 



Pepsin, 75, 193 



Peptide linkage, 47 



Peptones, 75 



Perception of gravity, 117 



Perfusion fluids, 59, 142 



of frog heart, 223 



Peripheral resistance in arterioles, 145 

 Peristaltic contraction, 79 

 Permeability change in secreting cells, 

 82,84 



of blood vessels, 137, 140 



of cell membranes, 9, 10, 16 



- of cells, 1 68 



- of membranes to solids, 10 

 Peroxidase, 91 



nature of, 91 



- of horse-radish, 203 

 Peroxides, 55, 90, 203 

 Phagocytosis, 135 

 Phase, 8 



difference in compound sounds, 1 12 

 Phloroglucin, 212 



