Answers:
1. c. help the digestive system function properly
2. d. all of the above
3. Cover your nose and mouth when sneezing or coughing, wash your hands often, and clean frequently touched objects.
4. Wet your hands with clean, running water. Lather your hands up with soap. Wash the soap and water between your fingers, on each side of your hands, and under your nails. Then rinse and dry them with a clean towel.
5.The immune system is a defense system of biological structures that protects our body from harmful microbes to prevent disease.
6. a. is an unknown substance that infects the body
7. True
8. c. destroy infections
9. b. an antibody
10. False