CBSE Class 10 Answered

1) Anaerobic respiration: Here the first step is the break-down of glucose into a three-carbon molecule called pyruvate. This process takes place in the cytoplasm. Further, the pyruvate may be converted into ethanol and carbon dioxide. This process takes place in yeast.

2) Aerobic respiration : During aerobic respiration, first glucose is broken down into pyruvate and then  the three-carbon pyruvate molecule is broken down to give three molecules of carbon dioxide and water.