Immune System Flashcards
The skin is an example of a(n) _____. Physically, the outer layer is highly-crossed-linked keratin and is waterproof, blocking many invaders and their toxins.
Non-specific barrier.
The body has three lines of defense against attack by foreign invaders: ____, ____, and ____.
Non-specific barriers;
Non-specific defenses;
Specific defenses.
Invaders not only have difficulty penetrating the skins structure, they are also repelled or destroyed by the skins ____.
Acid secretions.
Tears, saliva, and other secretions include lysozyme which ____.
Break down bacterial walls.
Mucous membranes and the cells that line then serve as a(n) ____: invaders become trapped in the mucous and are swept out by ____.
Non-specific barrier;
Ciliated cells.
Most microbes living in the food or drink which we ingest are destroyed by ____ before they can cross into the body: this is an ____.
Gastric juices;
Non-specific barrier.
____ are found in many bodily surfaces:; they remove nutrients and other materials that would otherwise be available to pathogenic species.
Symbiotic bacteria.
The second line of defense in the immune system uses ____ to attack a(n) ____ invader.
Chemical and cellular methods;
Unrecognized.
Lymphocytes which mature in the lymph system (as opposed to in the marrow or thymus) are called ____, and are a part of the non-specific defense system.
Natural killer (NK) cells.
____ recognize cells whose surface markers are drastically “non-self” - missing major markers or containing non-human glycoproteins - and kill them. (They [are/are not ?] phagocytic.)
NK cells;
Are not.
Most microbes living in the food or drink which we ingest are destroyed by ____ before they can cross into the body: this is an ____.
Gastric juices;
Non-specific barrier.
____ are found in many bodily surfaces:; they remove nutrients and other materials that would otherwise be available to pathogenic species.
Symbiotic bacteria.
The second line of defense in the immune system uses ____ to attack a(n) ____ invader.
Chemical and cellular methods;
Unrecognized.
Lymphocytes which mature in the lymph system (as opposed to in the marrow or thymus) are called ____, and are a part of the non-specific defense system.
Natural killer (NK) cells.
____ recognize cells whose surface markers are drastically “non-self” - missing major markers or containing non-human glycoproteins - and kill them. (They [are/are not ?] phagocytic.)
NK cells;
Are not.
