Circulation, Assimilation and Excretion 429 



12. In what way does it help us to know the direction in which blood 

 flows? 



13. Name three points where you can easily feel your pulse. 



14. What are the ductless glands? How do they act? 



15. How does the use of water aid our circulatory system? 



16. Complete the following statements: 



(a) Oxygen is carried in the blood by the . 



(b) Blood vessels carrying blood from the heart are called . 



(c) The blood gives to the air sacs of the lungs and takes 



from them. 



PROJECTS 



1. Obtain and examine carefully the heart of a sheep or cow. Compare 

 it with the human heart as described in the text. 



OUTDOOR OBSERVATION 

 Note change of putse when standing, walking, climbing and running. 



REFERENCES 



The Human Mechanism Hough and Sedgwick 



The Human Body . Martin 



