Typically, you will see the equation for cellular respiration represented in the equation below. CeHrzOo + 6
Oz+
5CO2 + SHzO + EnergY
This equation represents aerobic cellular respiration. Aerobic respiration occurs in the mitochondria of eukaryotic cells and only in the presence of oxygen. Aerobic cellular respiration is a very efficient process which yields up to 38 molecules of ATP for each
molecule of giucose.
Aerobic cellular respiration is not the only form of cellular respiration that occurs in living things. Cellular respiration also occurs if no oxygen is present in a process known as anaerobic respiration. Anaerobic respiration is much less efficient at converting glucose into ATP, yielding only 2 molecules of ATP for each molecule of glucose.
Additionally anaerobic respiration produces lactic acid or ethanol as products.
Today, you will be studying aerobic cellular respiration in soy beans. As a measure of cellular respiration, you will be looking at the oxygen consumption ofthe beans. lf the beans are carrying out aerobic respiration, they will be using oxygen. To measure oxygen consumption, you will be constructing a device called a respirometer. The respirometer will be submerged in water and as the beans use oxygen, water will enter the respirometer. By measuring the volume of water that enters the repirometer, we can determine the amount of oxygen being used by the beans.
You will be using three respirometers today. One will contain germinated soy beans, one will contain ungerminated soy beans with a small amount of gravel, and the last respirometer will contain only gravel. The soy beans that are germinated have been soaked in water which starts their growth process. These beans should