RESPIRATION
It is the oxidation of the food material in cells to release energy for various life
processes.
Some organisms use oxygen to breakdown glucose into CO2 and water. Some do not
use oxygen.
Experiment to prove release of CO2 during respiration in human
• Take some freshly prepared lime water in 2 test tubes.
• In one, blow air through lime water. It immediately turns lime water milky.
• In other test tube, pass air using a syringe or pichkari. It takes much time to
turn the lime water milky.
• It shows that the breath-out air contains more CO2 as compared to atmospheric
air.
_______________________________________________________________
Experiment to prove release of CO2 during respiration in Yeast
• Add some yeast to fruit juice or sugar solution. Take this mixture in a test tube
fitted with a one-holed cork.
• Fit the cork with a bent glass tube. Dip its free end into a test tube containing
freshly prepared lime water.
• Air taken out through the tube makes lime water milky. It is due to the
production of CO2 in the mixture of yeast & sugar solution. Here, fermentation
occurs.
In all types of respiration, the first step is the breakdown of glucose (6-carbon)
into pyruvate (3-carbon). It takes place in the cytoplasm.
It is the oxidation of the food material in cells to release energy for various life
processes.
Some organisms use oxygen to breakdown glucose into CO2 and water. Some do not
use oxygen.
Experiment to prove release of CO2 during respiration in human
• Take some freshly prepared lime water in 2 test tubes.
• In one, blow air through lime water. It immediately turns lime water milky.
• In other test tube, pass air using a syringe or pichkari. It takes much time to
turn the lime water milky.
• It shows that the breath-out air contains more CO2 as compared to atmospheric
air.
_______________________________________________________________
Experiment to prove release of CO2 during respiration in Yeast
• Add some yeast to fruit juice or sugar solution. Take this mixture in a test tube
fitted with a one-holed cork.
• Fit the cork with a bent glass tube. Dip its free end into a test tube containing
freshly prepared lime water.
• Air taken out through the tube makes lime water milky. It is due to the
production of CO2 in the mixture of yeast & sugar solution. Here, fermentation
occurs.
In all types of respiration, the first step is the breakdown of glucose (6-carbon)
into pyruvate (3-carbon). It takes place in the cytoplasm.
