Sah 105
Nonspecific Defenses (passive immunity)
TRUE OR FALSE?
_____ 1. The skin is the single most important defense the body has.
_____ 2. Sneezing removes pathogens from your nose.
_____ 3. Sweat, mucus, tears, and saliva are all types of mechanical barriers used to protect you.
_____ 4. The inflammatory response is part of the body’s first line of defense.
_____ 5. Leukocytes are white blood cells that fight infections and get rid of debris.
_____ 6. Barriers that keep out pathogens are the body’s first line of defense.
_____ 7. The second line of defense attacks pathogens that manage to enter the body.
_____ 8. The second line of defense includes mechanical, chemical, and biological barriers.
_____ 9. The first line of defense includes the inflammatory response and phagocytosis.
_____ 10. A nonspecific defense can be tailored to a particular pathogen.
_____ 11. The inflammatory response is triggered by chemicals called histamines and cytokines.
_____ 12. Biological barriers include millions of harmless bacteria live on the human skin.
The First Line of Defense
The body’s first line of defense consists of different types of barriers that keep most pathogens out of the body. Pathogens are disease-causing agents, such as bacteria and viruses. These and other types of pathogens are described in the figure below. Regardless of the type of pathogen, however, the first line of defense is always the same.
Types of pathogens that commonly cause human diseases include bacteria, viruses, fungi, and protozoa.
Which type of pathogen causes the common cold? Which type causes athlete’s foot? (
Mechanical Barriers
Mechanical barriers physically block pathogens from entering the body. The skin is the most important mechanical barrier. In fact, it is the single most important defense the body has. The outer layer of the skin is tough and very difficult for pathogens to penetrate. Mucous membranes provide a mechanical barrier at body openings. They
TRUE OR FALSE?
_____ 1. The skin is the single most important defense the body has.
_____ 2. Sneezing removes pathogens from your nose.
_____ 3. Sweat, mucus, tears, and saliva are all types of mechanical barriers used to protect you.
_____ 4. The inflammatory response is part of the body’s first line of defense.
_____ 5. Leukocytes are white blood cells that fight infections and get rid of debris.
_____ 6. Barriers that keep out pathogens are the body’s first line of defense.
_____ 7. The second line of defense attacks pathogens that manage to enter the body.
_____ 8. The second line of defense includes mechanical, chemical, and biological barriers.
_____ 9. The first line of defense includes the inflammatory response and phagocytosis.
_____ 10. A nonspecific defense can be tailored to a particular pathogen.
_____ 11. The inflammatory response is triggered by chemicals called histamines and cytokines.
_____ 12. Biological barriers include millions of harmless bacteria live on the human skin.
The First Line of Defense
The body’s first line of defense consists of different types of barriers that keep most pathogens out of the body. Pathogens are disease-causing agents, such as bacteria and viruses. These and other types of pathogens are described in the figure below. Regardless of the type of pathogen, however, the first line of defense is always the same.
Types of pathogens that commonly cause human diseases include bacteria, viruses, fungi, and protozoa.
Which type of pathogen causes the common cold? Which type causes athlete’s foot? (
Mechanical Barriers
Mechanical barriers physically block pathogens from entering the body. The skin is the most important mechanical barrier. In fact, it is the single most important defense the body has. The outer layer of the skin is tough and very difficult for pathogens to penetrate. Mucous membranes provide a mechanical barrier at body openings. They