I. Indicate which organ system will be primarily used in the following situation. Write the beginning letter of correct organ system on the blank. M muscular system D digestive system C circulatory system Sekeletal system R respiratory system N nervous system U urinary system I immune system E endocrine 1. Prepare for a 5km run and eat lots of carbohydrates like rice to give you more energy 2. You lift your feet and move your legs as fast as you can. 3. But you have to go to the bathroom because you drank too much water before the run. 4. Your breathing is getting faster and faster. 5. The heart is pumping fast as you sprint for the final 1km. 6. You enjoy attending the zumba activities 16