Claudia stood solemnly in her bedroom as she anxiously thought about the math test she had tomorrow. She is trying to study, but is way too hungry.
Claudia's nerves about her math test stimulates her sympathetic nervous system, which accelerates her heartbeat and makes her sweat.
2 + 2 = 4?
Claudia could not focus on her studying without fulfilling her need for a nice meal. Claudia's hunger caused her to get up and go to the kitchen to look for some food.
Claudia eats the chocolate chip cookies, which supply her with glucose, a major source of energy in her body. She also eats a cheeseburger, the carbohydrates stimulating the neurotransmitter serotonin, which helps calm her anxiety.
By fulfilling her hunger, Claudia helped her body to maintain homeostasis, which is the maintenance of a steady internal state.
Now that Claudia is full, happy, and determined to get a good grade on her math test, she is given the incentive to study for her math test, which she does for the rest of the night.