PHYSICAL EDUCATION CLASS C OORDINATED BY MRS BLESSING TITILOYE           Week: Nine Class: SS1 Lesson Title: Respiratory system Period: I-II Duration: 80 Minutes Learning Objectives: Students should be able to know:                        i.     Structure and functions of the lungs                      ii.     International and external respiration                    iii.      Mechanism of breathing                    iv.      An aerobic and anaerobic respiration Respiratory System Respiration refers to the union of oxygen with food in the cells (oxidation) resulting in the release of energy, heat, carbon(iv)oxide and water. Respiration covers a wide range of processes include the taking in of oxygen which is inhalation, the sending out of carbon(iv)oxide which is exhalation and the use of the oxygen intake. There are two processes of respiration 1) Breathing or external respiration. 2) Internal respiration or tissue respiration.   External respiration is