The space exploration program has hired you for advice on how to keep astronauts healthy in the space shuttle. How can the program's doctors make sure the astronauts’ bodies work well enough to exercise in space?

• The doctors could make sure that the astronauts’ bodies can make enough energy by getting enough sleep.

• The doctors could make sure the astronauts’ stomachs are getting the molecules they need from food and air.

• The doctors could make sure the astronauts’ cells are getting the molecules they need from food and air.

• The doctors could make sure the astronauts’ cells are getting different types of molecules from food.

Doctors tested a patient and found that his cells contained normal levels of oxygen and glucose molecules, and no starch molecules. Will this patient be able to exercise normally?

• Yes, the glucose and oxygen molecules can react together to release energy for the body to function.

• No, his digestive system is not breaking down food molecules; his cells need starch molecules to react with glucose, which releases energy.

• No, his body systems are working, but he needs to eat different food; in cells, only amino acids can react with oxygen to release energy.

• Yes, as long as his cells have glucose, they don’t need anything else to release energy for the body to function.

Some problems with the digestive system make it very difficult for the body to digest enough food. Why would it be harder to exercise when you have a digestion problem like this?

• You would not be able to sleep, which would make you too tired to exercise.

• Your cells would have molecules from air, but would not get enough molecules from food.

• You would need to breathe in a lot more air because your body would have fewer molecules from food.

• You would not get any of the molecules your cells need to exercise.

The test report above shows the level of molecules in different parts of the patient’s body. How would you expect this patient to do on an exercise test?

• Well; his body is working properly.

• Poorly; his digestive system is not combining glucose molecules together for the cells to use.

• Poorly; his digestive system is not breaking down molecules from food into glucose.

• Poorly; his respiratory system is not breaking down oxygen molecules into glucose.

Two soccer teams, the Bears and the Panthers, played games at the same time in two different locations. The Bears game was played at sea level, where there is a normal amount of oxygen. Before their game, the players on the Bears ate a lunch of mostly starch. The Panthers game was played at very high altitude, where there is less oxygen. The players on the Panthers ate a lunch of starch and protein. Which team probably did better in their game?

• The Bears probably did better because their cells released energy from oxygen reacting with glucose, which was broken down from starch in the digestive system.

• The Panthers probably did better because their cells released energy from breaking down protein in the digestive system, which then combined with oxygen in cells.

• The teams did equally well because their digestive systems just need to break down starch into glucose for cells to release energy.

• The teams did equally well because glucose from starch can react with oxygen or proteins to release energy.

A student thinks that the human body only works properly when cells are getting molecules from food and molecules from air. Is the student correct?

• Yes, the body only works when cells get molecules from food and molecules from air.

• No, the body only works when cells are getting molecules from different types of food.

• No, the body only works when the lungs get molecules from air, and the stomach gets molecules from food.

• No, the body works as long as cells are making all the molecules they need.

Stella’s respiratory system is not working well. Why is this a problem for her ability to exercise?

• Her respiratory system will not be able to break down molecules from air into oxygen.

• Her cells will not work well when they have low levels of oxygen.

• Her digestive system will have to work twice as hard to get the same amount of energy from glucose molecules.

• Her cells will not work because molecules from air will be too large for her body to use.

Doctors tested a patient to find out what molecules were in her cells. Her cells contained normal levels of oxygen molecules, low levels of amino acid molecules, and low levels of glucose molecules. Will this patient be able to exercise normally?

• Yes, as long as her cells have enough oxygen, her body will be able to exercise.

• No, her cells need glucose to react with oxygen to release enough energy to exercise.

• No, her cells need amino acids to react with oxygen to release enough energy to exercise.

• No, her cells need glucose to react with amino acids to release enough energy to exercise.

Asthma is a condition in which it can be very hard for a person to breathe in enough air. Would it also be difficult for someone with asthma to exercise?

• No, as long as the person is getting enough sleep, he will make enough energy to exercise.

• No, as long as the person's cells are getting different types of molecules from food, he can still exercise.

• No, the person's cells may not have everything they need, but his body can still exercise normally.

• Yes, it will be difficult for a person with asthma to exercise because his cells need molecules from air.

Jamal ate a meal of rice before seeing his doctor. Rice is made of mostly starch molecules. Jamal has been feeling tired a lot, so his doctor gave him a test that found that Jamal’s cells contained normal levels of oxygen and low levels of glucose. Does this explain why Jamal has been feeling tired?

• Yes, Jamal’s respiratory system is working, but his digestive system is not turning the oxygen into glucose.

• Yes, Jamal’s respiratory system is working, but his digestive system is not breaking down starch molecules into glucose for his cells.

• Yes, Jamal’s digestive system is working, but his respiratory system has too much oxygen, so his body stopped making energy.

• No, something else must be wrong with Jamal because his cells have all the molecules they need.