Metabolism Critical Juncture

Two teams of scientists hiked 10 kilometers to different study sites. Before their hike, the Valley team ate a lunch of mostly protein. The Mountain team ate a lunch of a mix of starch and protein, but hiked at high altitude, where there is much less oxygen. Which team probably had an easier time hiking?

• Both teams had an easy time hiking because their digestive systems broke down proteins into amino acids for cells to release energy.

• Neither team had an easy time hiking; the Valley team’s cells needed more glucose from broken-down starch for a reaction, and the Mountain team’s cells needed more oxygen from air.

• The Mountain team had an easier time hiking; their cells released energy from protein reacting with glucose, which was broken down from starch in the digestive system.

• The Valley team had an easier time hiking; their cells released energy from protein breaking down in the digestive system, which then combined with oxygen in cells.

The test report above shows the level of molecules in different parts of the patient's body. What does this test indicate about how her body systems are working?

• Her body systems are working properly.

• Her respiratory system is not breaking down molecules from air.

• Her digestive system is not breaking down molecules from food.

• Her digestive system is not combining molecules together.

Rico, a scuba diver, uses breathing gear to help him breathe air underwater. He always gets enough sleep and eats a good breakfast before a dive. What could happen if his breathing gear broke during a dive and he could not breathe as much air as usual?

• It would be difficult to swim, because his cells cannot work without molecules from air.

• It would not affect him because his cells are getting the different types of molecules they need from food to work properly.

• It would not affect him as long as he slept enough.

• It would not affect him because his body can function normally even if his cells do not have molecules from air.

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

• Yes, his body is working properly enough to exercise.

• 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; only proteins can react with glucose to release energy.

• No, his respiratory system is not working; his cells need oxygen to react with glucose, which releases energy.

8. Raoul ate a meal of oats before seeing his doctor. Oats are made of mostly starch molecules. Raoul feels tired, so his doctor gave him a test and found that Raoul’s cells contained glucose molecules, but they did not contain enough oxygen molecules. Does this explain why Raoul feels tired?

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

• Yes, his digestive system is breaking down starch molecules, but his respiratory system may not be working properly.

• Yes, his respiratory system is working, but his digestive system is not getting energy from combining glucose molecules.

• Yes, his digestive system is working, but his respiratory system is not breaking down oxygen, so his body stopped making energy.

If a person is breathing normally, which of the following could prevent him from using his body to exercise normally?

• not getting enough sunlight, because cells need sunlight to function

• not getting enough sleep, because the body only makes energy for exercise while asleep

• not eating enough food, because cells need molecules from both food and air to work

• nothing, because he would be able to exercise normally as long as his cells are getting molecules from the air

A patient has been eating healthy foods, but his digestive system is not doing what it usually does. Can this patient still exercise normally?

• Yes, as long as he can still breathe, his cells will have all the molecules they need to release energy.

• No, his digestive system is not breaking down oxygen into molecules small enough to get inside his cells.

• No, molecules from food are not combining together to be large enough for his cells to use.

• No, molecules from food are not getting broken down small enough to get inside his cells.

The tables above show information about the body systems of three different patients. Which of these patients’ bodies are NOT working well enough to exercise normally?

• R. Frost only

• V. Mistry only

• R. Frost and A. Kim

• A. Kim and V. Mistry

4. An ocean scientist plans to spend several days underwater in a submarine. Doctors on land will monitor her body to make sure she is healthy during her trip. What is one way doctors will be able to tell whether her body is healthy enough to do all her tasks while she is in the submarine?

• The doctors could see if her cells are getting several different types of food molecules.

• The doctors could see if she is getting plenty of sleep so her body can make enough energy.

• The doctors could see if her lung cells have molecules from air, and her stomach cells have molecules from food.

• The doctors could see if her cells are getting the molecules they need from food and air.

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

• Yes, her cells just need to combine amino acids to release energy.

• No, her cells need to combine glucose into starch molecules to release energy.

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

• Yes, her cells just need oxygen to release energy.