PROBLEM 144 165 



Problem 141 : Adaptations of appendages for locomotion. 



Observations. — Locate the appendages. How many do you 

 find? What differences do you find between the fore and hind 

 legs? What purposes do the hind legs serve? The fore legs? 



Conclusion. — 1. Show exactly how the legs of the frog are 

 fitted for locomotion. 



2. Of what kind of locomotion is the frog capable? 



Problem 142 : Adaptations for sensation. 



Observations. — Touch the frog gently (if possible without its 

 seeing you) . How does it respond ? How is the eye fitted for its 

 work (position, movement, etc.) ? How is the eye protected? 

 Touch it. Back of the eye find the eardrum. Describe it in size 

 and position. 



Conclusion. — What are the uses of each of the sense organs ? 

 Give experimental proof if possible. 



Problem 143 : Adaptations for food getting. 



Method and Observations. — Open the mouth of a freshly killed 

 frog and move the tongue. Compare with figure on page 242, 

 Civic Biology. Feel both jaws to find whether the frog has teeth. 

 Feel the roof of the mouth. 



Conclusion. — Write a paragraph telling how the frog uses its 

 tongue and teeth in catching its prey. 



Problem 144 : Adaptations for breathing. 



Method. — Watch carefully the throat and sides of a frog that 

 has its head out of water. Note the pulsations of the throat. 

 Count the number of movements per minute. 



Note that every so often another more noticeable movement 

 occurs. What happens to the nostril holes when this movement 

 takes place ? Does this latter movement, when the nostril holes 

 are closed, make the mouth cavity larger or smaller ? 



Examine a dissected specimen, or chart showing glottis, 

 trachea, bronchial tube, and lungs. Insert a blowpipe in the 

 glottis and inflate the lungs. Are they elastic? 



