The Immune System

Question 1

Immunity

Answer 1

the ability to resist injuries and diseases caused by foreign substances; degree of immunity can change

Question 2

Pathogen

Answer 2

any disease causing organism; primary types include: bacteria, viruses, fungi, protists, parasites, and harmful chemicals or toxins

Question 3

What are the two basic types of immune defenses?

Answer 3

Nonspecific defenses and specific defenses

Question 4

Nonspecific defenses

Answer 4

all-around defense mechanisms that do not distinguish one type of threat from another; prevent the pathogen from contacting the body; prevent the pathogen from entering body tissues; limit the spread of the pathogen if it does enter the tissues; assists the specific immune response

Question 5

Examples of nonspecific defenses

Answer 5

physical barriers (skin, mucus membranes, cilia, hair, gastric juices, tears, urine, saliva); phagocytes (neutrophils, eosinophils, monocytes); immunological surveillance (cancer cells, cells that are infected with viruses); Interferons; Complement (a group of blood plasma proteins that act to support the action of antibodies); inflammatory response (restricts the spread of pathogens, mobilizes and concentrates the defenses, inhibits movement to promote healing); fever (inhibits pathogen growth and survival, increases metabolic rate, which increases the speed of the immune system response)

Question 6

Specific defenses

Answer 6

very specialized mechanisms that are designed to focus on particular threats; adaptable and capable of becoming very powerful; focuses on very specific pathogens; response is heavily dependent on the activities of lymphocytes; creates a state of “immunity” that provides better protection if future exposures to the same pathogen occur; the system has a memory

Question 7

Steps of specific immune response

Answer 7

the body is exposed to a particular antigen for the first time; antigen is attacked by the primary weapons of the specific response (lymphocytes and antibodies); successful clone attacks the antigen and stimulates the mass production of more lymphocytes of the same clone type; memory cells are produced by the successful clone; the antigen is gone and body returns to normal; the body is exposed to same antigen and reacts much quicker

Question 8

Natural Killer Cells

Answer 8

seek out abnormal cells and destroy them

Question 9

Interferons

Answer 9

chemical messengers that are released locally; goal is to interfere with normal viral replication

Question 10

Antigen

Answer 10

a pathogen that triggers the specific immune response

Question 11

Lymphocytes

Answer 11

these cells are the cornerstone of the entire specific response; some lymphocytes engulf the antigen directly, other lymphocytes make antibodies

Question 12

Antibodies

Answer 12

proteins made by certain lymphocytes that directly attack antigens

Question 13

Antibodies

Answer 13

proteins made by certain lymphocytes that directly attack antigens

Question 14

T Cells

Answer 14

lymphocytes that attack antigens directly, by phagocytes

Question 15

B Cells

Answer 15

lymphocytes that make antibodies

Question 16

Memory Cells

Answer 16

lymphocytes that are stored in reserve for future protection

Question 17

Helper T Cells

Answer 17

lymphocytes that stimulate and control the response of both T Cells and B cells

Question 18

Great Flu Pandemic of 1918 (The Spanish Flu)

Answer 18

killed at least 25 million people, flu virus, pandemic is long over

Question 19

The Bird Flu

Answer 19

H5N1, transfers from poultry to humans

Question 20

The Bubonic Plague (Black Death)

Answer 20

bacterial infection, carried my small mammals, very deadly

Question 21

Malaria

Answer 21

500 million people worldwide may be infected, 1 million people die each year, parasitic disease, no successful vaccine

Question 22

Smallpox

Answer 22

viral disease, 3.5 million Native Americans died, has been eradicated worldwide

Question 23

Viral Hepatitis

Answer 23

viral disease, affects the liver, transfers from blood to blood contact or fecal/oral contact, vaccines only exist for Hep A and B