1.60. Barriers to Pathogens http://www.ck12.org
FIGURE 1.120
This is what the cilia lining the lungs
look like when they are magnified. Their
movements constantly sweep mucus and
pathogens out of the lungs. Do they
remind you of brushes?
Vocabulary
- cilia: Tiny finger-like projections; in the mucous membranes they move in waves and sweep mucus and
trapped pathogens toward body openings. - mucous membrane: Lining of inner body surfaces and body openings that produces mucus.
- mucus: Sticky, moist substance that traps pathogens and debris.
Summary
- Your body’s first line of defense includes the skin and other barriers that keep pathogens out of your body.
- Most body fluids that you release from your body contain chemicals that kill pathogens.
Practice
Use the resource below to answer the questions that follow.
- Introduction To How The Immune System Worksat http://www.youtube.com/watch?v=IWMJIMzsEMg
(3:16)