Chapter 9: The Immune System And Mechanisms Of Defense

Front 1

pathogens

Back 1

-come from the outside body - account for a large fraction of all human disease and suffering -mutations cause our own cells to become abnormal and may even lead to cancer. luckily our cells recognize abnormal cells and destroy most before they develop

Front 2

our body's immune system and General defense mechanisms

Back 2

1) barriers to entry or ways of expelling or neutralizing pathogens beforehand can do harm . includes: skin, stomach acid, tears, acts of vomiting and defecation
2) nonspecific defense mechanisms: help the body respond to generalized tissue damage and many of the more common or obvious pathogen, including most bacteria and some viruses.
3) specific defense mechanisms: enable the body to recognize and kill specific bacteria and other foreign cells and to neutralize viruses. they employ sophisticated weaponry, and are also the basis of immunity from future disease.

Front 3

bacteria

Back 3

-single celled organisms that don't have a nucleus and all DNA is in one chromosome - their small size is an advantage because they have high surface area which allows them to get raw materials and rid of waste by diffusion.
-although many are harmless and somewhat beneficial, some bacteria are pathogens.
-bacterial infections are treated with antibiotics

Front 4

viruses

Back 4

-small infectious agents, consisting of a small piece of genetic material surrounded by protein coat. they have no organelles of their own.
-when they enter a long cell they take it over and use it to make more viruses.
-they enter by being taken in by cytoplasm by endocytosis, or merging outer coat with cell membrane, and by attaching to the outer surface and injecting genetic material into cell
-antibiotics don't work. either prevent virus from entering living cell or stop host cell from producing viruses once infected

Front 5

prion

Back 5

-misfolded form of normal brain cell protein -triggers other normal proteins nearby to misfold
-once prion enters nerve cell the misfolding process becomes self propagating
-associated with mad cow disease and vCJD
-no cure for prion infection

Front 6

lymphatic system

Back 6

-helps maintain the volume of blood in cardiovascular system
-transports fat and fat-soluble vitamins absorbed from the digestive system to the cardiovascular system
-defends the body against infection
basic components are network of lymph vessels throughout the body, the lymph nodes, the spleen, the thymus gland, and the tonsils and adenoids

Front 7

lymphatic capillaries

Back 7

-Have wide spaces between overlapping cells which allows them to take up substances that are too large to enter a blood capillary
-lymph is a milky substance made up of wbc's proteins fats and occasional virus or bacterium.
-lymph calories merge to form lymphatic vessels. flow is aided by skeletal muscle contractions.
-vessels merge to form two major lymphatic ducts: right lymphatic duct, and thoracic duct. both join subclass veins and return lymph back to cardiovascular system

Front 8

lymph nodes

Back 8

-remove microorganisms, cellular debris, and abnormal cells from lymph before returning it to cardiovascular system
-hundreds cluster in areas of digestive track, neck, arm pits, and groin
inside each node are connective tissue and macrophages and lymphocytes. Lymphatic vessels carry lymph in and out of node and valves within vessel ensure lymph flows in one direction

Front 9

spleen

Back 9

-largest lymphatic organ, soft fist sized mass located in upper left abdominal

-covered with dense connective tissue interspersed with smooth muscle. the inside has two types of tissue red pulp and white pulp.