ELEMENTARY PHYSIOLOGY 



QUESTIONS ON LESSON XXIX, 



1. Describe the general form, size, and position of the kidneys. 



2. Describe the structure of the kidney as far as it can be seen without the 



use of a microscope. 



3. Name the vessels of the kidney. Describe the nature of the fluid contained 



in each, and say in which direction it flows. 



4. Compare the blood of the renal artery with that of the renal vein. 



5. In what way do the kidneys purify the blood ? Should the kidneys cease 



to perform their function, is it likely that other organs would do their 

 work ? Give reasons for your answer. 



6. Describe the nature of the urine. How does it get from the kidneys to the 



bladder, and what prevents it from immediately leaving the bladder ? 



7. Describe the chemical composition of the chief ingredients separated from 



the blood by the kidneys. How did these materials get into the 

 blood ? 



8. Describe the structure and use of the bladder. 



9. Describe the manner in which the urine is separated from the blood as it 



circulates in the kidney. 



LESSON XXX. 



THE NERVOUS SYSTEM NERVES. 



ALMOST every movement of the body, whether voluntary or 

 involuntary, is brought about and governed by some portion of 

 the nervous system. If we will to do anything, we do it through 

 the agency of nervous matter, which acts as a medium between 

 the mind and the muscles. Thus the nerves do not produce 

 motion by their own contraction, but by their influence over the 

 muscles in which their fibres terminate. 



The nervous system consists of two distinct parts, called the 

 cerebro-spinal and the sympathetic systems. 



The cerebro-spinal system consists of the brain, the spinal 

 cord, and all the nerves given off from the brain and the cord. 

 All the vertebrate animals possess such a system. The nerve 

 fibres of the cerebro-spinal system are distributed chiefly to the 

 skin, thus giving us the sense of touch ; to the other organs of 

 sense the nose, tongue, ear, and eye ; and also to all the voluntary 

 muscles. 



The sympathetic or ganglionic system consists of a number of 

 ganglia (knots) of nervous matter which give off nerve fibres. The 

 chief portion of this system comprises a double chain of ganglia, si- 

 tuated one half on each side of the vertebral column, and extending 

 from the skull to the pelvis. It also includes various ganglia 

 which supply fibres to certain internal organs. The nerves of the 



