A. How is the villus the functional unit of the small intestine? In your answer, include a discussion of its structure and function and the enzymes found there. What is the importance of surface area to the functioning of the villi?
B. What triggers your body to take a breath? Surprisingly, blood oxygen levels are not the most influential factor. Explain what part of the brain stimulates breathing and what aspects of body chemistry are important in controlling the rate and depth of your breathing.