824 TEST QUESTIONS FOR STUDENTS 



1 1 8. Explain five of the many ways in which a flying-bird's skeleton 

 is adapted for flight. 



119. What orders of Mammals have at the present day thoroughly 

 wild representatives in Britain? Give two examples of each, and, 

 selecting one from the air, one from the water, and one from under 

 the earth, show how each is specially adapted to its mode of life. 



1 20. What are the peculiarities in the blood of Mammals as compared 

 with that of other Vertebrates ? 



121. In what respects is a Dog's skull adapted to a Carnivore's life ? 

 [(i) Strong occipital and sagittal crests for the insertion of muscles 

 from the neck and from the jaw. (2) Prominent zygomatic arch 

 leaving room for strongly developed muscles in the temporal fossa. 

 As a consequence of this the orbit is confluent with the temporal fossa. 

 (3) The glenoid fossa is deep, sub-cylindrical, with a post-glenoid 

 process, preventing backward slipping. (4) Strong killing canines 

 and specialised back-teeth (carnassials or sectorials) for cutting, and 

 so on.] 



122. What passes from mother to offspring, from offspring to 

 mother, through the placenta characteristic of most mammals ? [From 

 the maternal blood there diffuses into the foetal blood: (i) dissolved 

 nutritive materials, (2) oxygen, (3) water and salts, and (4) hormones. 

 From the foetal blood there diffuses into the maternal blood : (i) nitro- 

 genous waste-products, (2) carbon dioxide, (3) hormones.] 



123. In what ways are British bats adapted to the conditions of 

 their life? [Besides the adaptations directly implied in making the 

 wing, there is the lightness of build suited for aerial locomotion, there 

 is the keel on the sternum for the insertion of pectoral muscles, there 

 is the stiffness of the backbone, there is the great development of 

 tactility which is of obvious advantage in nocturnal animals, there is 

 the uniparous birth, and so on.] 



124. Mention three quite different ways in which British Mammals 

 meet the winter, giving an example of each. [Hibernation, in bats, 

 hedgehog, etc. ; storing, in squirrels, etc. ; turning white, in ermine 

 and mountain hare. ] 



125. What are the salient characters of a Mammal's skull? [A 

 simple mandible working on the squamosal, a complete bony palate, 

 two occipital condyles, the quadrate has become an ear-ossicle, there 

 are usually two sets of teeth in sockets, etc. ] 



126. Contrast the atlas and axis of a Mammal. [The atlas has 

 almost no centrum, deep anterior concavities for the condyles, almost 

 no neural spine, large transverse processes. The axis has a large 

 centrum (including the odontoid process which belongs to the atlas), 

 anterior convexities, a high neural spine, almost no transverse processes. ] 



127. Select one of the British Mammals and show how it is adapted 

 to the conditions of its life. [The burrowing mole has a broad hand 

 with an extra sickle bone, well suited to serve as a shovel ; very strong 

 pectoral girdle and muscles adapted to the hard work of burrowing ; 

 its half-finished eye is protected by the hair ; the absence of a pinna 

 reduces friction ; and so on. ] 



128. Name and define the various regions of the vertebral column 

 of a typical Mammal. . 



