Answer:
Step-by-step explanation:
This question comprises a couple of questions that are interwoven. However, the description below should suffice.
The part of the food she needs to go for the run is bread (starch) while the component of the air she requires is oxygen. This is because starch are polymers that are made of glucose monomers which are known sources of energy for the body. Air contains nitrogen, oxygen, carbon dioxide and rare gases; the oxygen from air here is necessary for many metabolic activities in the body during the race.
Her respiratory and her digestive system work together to provide her with the molecules (mainly oxygen and glucose) that she needs in her cells. The digestion of starch is a multienzyme process that is summarized as follows. The digestion of the starch (bread) begins in the mouth. The bread is acted upon by the enzyme amylase which is present in the saliva. The enzyme breaks down this starch into small glucose chains and then to dextrins and maltose (which is a disaccharide). The disaccharide is then broken down into glucose. Only a small fraction of the starch is broken down to glucose in the mouth. The broken and unbroken food substance is then taken to the stomach where little activity occur because of the acidic condition but the process continues/accelerates in the small intestine until alot of glucose is produced from the food (bread). The oxygen taken in through the respiratory system is then transported through the circulatory system to various parts of the body. The glucose molecules produced by the breakdown of starch is also diffuses into blood stream and taken up by various cells in the body.
The cells in her body convert these glucose to energy (ATP) through the process known as glycolysis (breakdown of glucose). This energy is what is released from her cells and then used to run.