Please answer this: I read this background article the other day: The lungs of mammals are unique in having alveoli . These are tiny, sac-like structures. Each alveolus is surrounded by a network of very small blood vessels (see Figure below ). Because there are millions of alveoli in each lung, they greatly increase the surface area for gas exchange between the lungs and bloodstream. Human lungs, for example, contain about 300 million alveoli. They give the lungs a total surface area for gas exchange of up to 90 square meters (968 square feet). That's about as much surface area as one side of a volleyball court! I am facing a new situation today: Two students learned about respiratory systems in animals. Dana learned more about mammalian lungs, while Barry learned more about the lungs of birds. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which student learned less about surface area for gas exchange between the lungs and bloodstream?
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Answer: Barry

Please answer this: I read this background article the other day: The brains of all mammals have a unique layer of nerve cells covering the cerebrum. This layer is called the neocortex (the pink region of the brains in Figure above ). The neocortex plays an important role in many complex brain functions. In some mammals, such as rats, the neocortex is relatively smooth. In other mammals, especially humans, the neocortex has many folds. The folds increase the surface area of the neocortex. The larger this area is, the greater the mental abilities of an animal. I am facing a new situation today: Two colleagues studied at the same university. Nick studied the brains of birds, while Joe studied the brains of mammals. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which colleague studied less about the neocortex?
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Answer: Nick

Please answer this: I read this background article the other day: An allergy is a disease in which the immune system makes an inflammatory response to a harmless antigen . Any antigen that causes an allergy is called an allergen. Allergens may be inhaled or ingested, or they may come into contact with the skin. Two common causes of allergies are shown in Figure below . Inhaling ragweed pollen may cause coughing and sneezing. Skin contact with oils in poison ivy may cause an itchy rash. Other common causes of allergies include dust mites, mold, animal dander, insect stings, latex, and certain food and medications. Symptoms of a common allergy such as pollen can include sneezing, a runny nose, nasal congestion and itchy, watery eyes. I am facing a new situation today: Two groups f people presented allergy symptoms. Group Alpha inhaled some allergens, but they were in a very protected environment, while Group Beta ingested some allergens and was exposed to a wide variety of other allergens. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which group had some people that were exposed to animal dander?
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Answer:
Group Beta