PROBLEM 186 223 



Examine carefully in a strong light each of your teeth and 

 answer the following questions, marking the points asked for 

 on a chart of your teeth copied from the preceding diagram. 

 1. With a bracket, label each group of teeth. 2. With a cross, 

 mark all the teeth you have lost or that have not grown. 3. Mark 

 all cavities not filled in your teeth by a spot where the cavity 

 exists. 4. If teeth have been filled, crowned, etc., mark with 

 appropriate title. 



Conclusion. — What is the condition of my teeth ? Should I 

 go to a dentist ? 



Problem, 186 : To demonstrate the function and structure of 

 a simple gland. 



Materials. — • FehUng's solution, test tube, cracker, stained 

 sUde showing longitudinal and cross sections of a gland. 



a. Function 



Method and Observations. — Think of a lemon or a pickle. 

 What happens in your mouth? Collect some of the saliva. 

 What is its appearance? 



Chew up a cracker having no sugar in it. After th(j mass is 

 well mixed with saliva put in the test tube and place the tube in 

 warm water for an hour. Then test with Fehling's solution. 

 What is the result ? 



Conclusion. — 1. With what structures in the human body is a 

 gland connected? 



2. What is one function of the juice poured out by the saUvary 

 glands of the mouth? 



b. Structure 



Observations. — Under the microscope, notice the structure of 

 a gland in both cross and longitudinal sections. With what is the 

 wall lined? What is the shape of the gland? (See textbook.) 

 If work is done by a gland, then it must have food to do this work. 

 Might the material poured out of a gland be manufactured from 

 the food it gets ? 



What structures would of necessity go to a gland to take food 

 there? Look at the diagram in your textbook. 



