Human defence systems

What is the first line of defense against pathogens?

• Stomach acid
• Tears
• Mucus
• Skin

How do ciliated cells in the trachea contribute to the body's defense system?

• Break down pathogens
• Engulf pathogens
• Produce antibodies
• Move pathogens towards the throat

How does skin act as a barrier to prevent infection?

• It traps pathogens in mucus
• It contains cilia
• It forms a scab
• It produces enzymes

What is the role of mucus in the nose in preventing infection?

• Trapping pathogens
• Producing antibodies
• Breaking down pathogens
• Engulfing pathogens

How do phagocytes destroy pathogens?

• Produce antibodies
• Move them towards the throat
• Trap them in mucus
• Engulf and break them down

What do lymphocytes produce to fight against pathogens?

• Enzymes
• Antibodies
• Phagocytes
• Antitoxins

How are antibodies and antitoxins produced by lymphocytes specific to pathogens?

• They are attracted to pathogens
• They are highly specific to the antigen on the pathogen
• They break down pathogens
• They engulf pathogens