Step 1
Imagine you are an oxygen molecule. Your job is to get inside the body and deliver oxygen to a working muscle. Create a word flowchart to identify all the structures you will encounter during your passage from the outside air to the inside of a muscle cell. Include a short description of how you will exchange places with carbon dioxide when you arrive at the cell.

Step 2
Prepare a paragraph explanation for each of these scenarios.
As Binah was leaving the gym, she was red-faced. She commented that she seems to always sweat through her face. Explain to her what’s really happening.
Calculate your own stroke volume and cardio output. Pharmacies often have free blood pressure cuffs for customers to use. Be sure to follow the directions. Explain how you calculated your stroke volume and cardiac output. How are these levels related to cardiorespiratory fitness? Explain.