Respiration

• Robert Boyel and Robert Hook first of all explained the meaning of respiration.
• Main aim of respiration is to liberate energy in the form of A.T.P.
• Oxidation of food takes place.
• C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + 38 ATP
• It is cetabolic process. It is exothermic process.
• If substrate is protein it is protoplasmic respiration.
• If substrate is carbohydrate or lipid it is floating respiration.
• Respiration is a physico-chemical process.
• In Man mainly Aerobic respiration occur.
• Lavozior explained use of O2  in aerobic respiration.
• In Man, in emergency anaerobic respiration may occur.
• In anaerobic respiration lactic acid and 2 ATP are formed.
• G.S. Cartor explained 2 phases.

1.      External Respiration -

It takes place outside cell.

It includes -

(1) In take of O₂  upto respiratory organ.                            

(2) Transport of O₂  from respiratory organ to cells.

(3) Transport of CO₂  from cells to respiratory organ.              

(4) Give out of CO₂  from lungs.

2.      Internal Respiration or Tissue Respiration or Cellular Respiration -

It includes glycolysis, kreb's cycle and ETS.

Respiratory organ is characterized by -

(1) More surface area                                           

(2) Thin membrane like

(3) Highly vascular                                               

(4) Surface is wet