Across
- 2. natural secretions by the skin to reduce friction and contain substances that prevent the growth of pathogens
- 6. white blood cells engulf and destroy foreign invaders through this process
- 8. single celled organism that can cause infection
- 9. mouth secretion, watery fluid that blocks the growth of pathogens
Down
- 1. a thick, slippery fluid that moistens and protects parts of the body
- 3. invasion of harmful, microscopic organisms
- 4. microscopic organisms
- 5. poisons
- 7. foreign substances in the body