2.50: Practical: Investigate Breathing in Humans, including the Release of Carbon Dioxide and the Effect of Exercise

INVESTIGATING RELEASE OF CARBON DIOXIDE DURING EXERCISE

s Diagram Showing the Test for Carbon Dioxide

METHOD: Measure a fixed volume of Limewater into a boiling tube Use a straw and blow into the solution of Limewater

RESULT: Limewater turns cloudy when Carbon Dioxide is present Hence, as respiration produces Carbon Dioxide as a waste product, blowing into a solution of Limewater will form a cloudy solution, therefore showing the production of Carbon Dioxide via respiration

INVESTIGATING EFFECT OF EXERCISE ON BREATHING

DURING EXERCISE, TWO TYPES OF RESPIRATION OCCUR: 1. AEROBIC RESPIRATION s 2. ANAEROBIC RESPIRATION s Diagram showing Different Types of Respiration

METHOD: Stationary breathing rate of participants is recorded Specific exercise will be performed by participants at the same intensity for a fixed period of time Breathing rate after exercise is recorded Results are compared

RESULT: During exercise, more energy is needed via respiration to allow muscle contractions to occur to facilitate movement Hence, the rate of breathing will increase to allow more Oxygen transport in blood to respiring cells for movement to occur If energy demand exceeds Oxygen intake, energy may be produced via aerobic respiration, producing Lactic acid as a waste product After exercise, breathing rate continues to increase as extra Oxygen is needed to break down the Lactic acid produced - Oxygen debt