TEST QUESTIONS FOR STUDENTS 829 



lishment of the central nervous system, of the primitive gut, of the 

 notochord, of the mesoblast-segments and ccelom.] 



187. How is it that the milk-glands of a mammalian mother come 

 to be actively ready when they are needed by the offspring ? 



1 88. Give three examples of definitely intelligent behaviour as 

 contrasted with instinctive behaviour. 



189. Give a short account of animal industries, considering them 

 as counterparts of human occupations. 



190. What are the main modes of inheritance ? 



191. In what structural respects does Man differ from the higher 

 apes? 



192. Can you throw any light on the most difficult problem in 

 biology the origin of the distinctively new ? 



193. Give with the help of a diagram a general account of the 

 circulation of the blood in a Mammal. 



194. What chemical compounds are of usual occurrence in animals? 

 [Proteins, carbohydrates, lipins or fatty substances, extractives (like 

 amino-acids, lactic acid, urea), salts, water.] 



195. What are proteins? [Nitrogenous carbon compounds, forming 

 an essential part of the physical basis of life, and often of the less 

 labile bodily framework. A typical chemical composition is CQQ O^ 

 N 16 H 7 S . 3 Ph.? . 3 .] 



196. Why must animals breathe? [Much of living is oxidation. 

 Oxygen must be brought in from outside to keep the fire of life 

 burning. The waste CO 2 , which would poison if it accumulated, 

 must be got rid of.] 



197. What is the origin of the nitrogenous waste that is got rid of 

 in excretion? [(i) From the fine waste of the protein framework, 

 owing to the wear and tear of life, and (2) from nitrogenous waste 

 involved in the utilisation of protein-food. ] 



198. Sum up the "evidence of evolution." [(a) Physiological, 

 e.g., variations, reversions, chemical evidence of blood-relationship. 

 (b} Morphological, e.g., homologies, vestigial organs, connecting links. 

 (<r) Historical, (i) the palaeontological history, and (2) the general 

 recapitulation of phylogeny in ontogeny.] 



199. Mention some of the chemical processes that commonly go on 

 in metabolism. [Oxidations, reductions (e.g., fats from sugars), 

 hydrations, dehydration syntheses (e.g., building up proteins), fer- 

 mentations.] 



200. Give an account of some of the chief modes of animal loco- 

 motion, [(a) Pushing the body along with an appendage or part 

 of the body pressed against a substratum, e.g., an insect walking; 

 (b} hauling the body up to a point of attachment, e.g., leech ; (<:) sculling 

 from behind, e.g., fish; (d) rowing in some form, e.g., ducknv^ 

 swimming with fore-limbs, bird flying. 1 



