chapter 13

Question 1

what is the Immune System’s purpose

Answer 1

• recognizes foreign material
• protects the body from anything that is not a part of the body

Question 2

what are the 3 lines of defense

Answer 2

1. external barriers
2. cellular and chemical components
3. to target specific pathogens

Question 3

how is skin a line of defense

Answer 3

• physical barrier
• resident microorganisms
• acidic pH and fatty acid content of sweat

Question 4

how are mucous membranes a line of defence

Answer 4

• cilia and mucus in respiratory system
• acidity of stomach
• fluids such as tears, saliva, and urine

Question 5

how does the spleen form a line of defense

Answer 5

• white pulp has immunological functions:
  phagocytic cells react to antigens in bloodstream
• macrophages in red pulp remove worn, damaged
  blood cells

Question 6

how is the lymphatic system part of a line of defense

Answer 6

responsible for collecting and returning excess
interstitial tissue fluid to cardiovascular system

Question 7

major lymph nodes

Answer 7

⚪ submandibular
⚪ prescapular
⚪ axillary
⚪ inguinal
⚪ popliteal

Question 8

what is Mucosa-Associated Lymphatic Tissue (MALT)

Answer 8

⚫clusters of lymphoid tissue in various areas
throughout the animal’s body
⚫located near mucosal surfaces: CALT, NALT, and GALT
⚫not encapsulated like a lymph node
⚫function:
-identify antigens, mount immune response

Question 9

are tonsils part of
MALT

Answer 9

yes

Question 10

what are peyer’s patches

Answer 10

⚫aggregations of lymphoid in small intestine
⚪ cattle, sheep, pigs, horses, dogs

Question 11

what type of WBC are found in the thymus

Answer 11

T lymphocytes

Question 12

what do T lymphocytes do

Answer 12

⚪ programmed to fight specific antigens
⚪ produced throughout life of the animal

Question 13

is the innate immune system specific

Answer 13

no

Question 14

what types of barriers does the innate immune system have

Answer 14

provides anatomical
and cellular barriers

Question 15

what anatomical barriers are on surface of body

Answer 15

• keratinized epithelial tissue of skin
• mucous membranes
  line respiratory, digestive, urinary, and reproductive systems
• tears, saliva, and nasal discharge production
• acidic environment of the stomach

Question 16

what is the second line of defense

Answer 16

when a pathogen
makes its way past
physical barriers,
the body controls
spread of infection
through acute
inflammation

Question 17

what is a fever

Answer 17

a systemic inflammation response where chemical
mediators are carried throughout the body

Question 18

what cells can do phagocytosis

Answer 18

neutrophils, monocytes, macrophages, dendrite cells

Question 19

what are the 5 steps of phagoocytosis

Answer 19

activation and
chemotaxis
attachment
ingestion
destruction
exocytosis

Question 20

what is compliment cascade

Answer 20

when one complement
protein is activated, it
activates the next
complement protein in the
series final result is
antigen cell lysis, or body cell apoptosis

Question 21

what are the 3 types of cytokines

Answer 21

⚪ interleukins
⚪ interferons
⚪ chemokines

Question 22

what are cytokines

Answer 22

• attract immune cells to specific site
• act as inhibitor molecules
• enhance the immune processes
• play a major role in hematopoiesis

Question 23

interleukin actions

Answer 23

promotes inflammation
affects metabolism
kills cells
affects leukocytes
affects cell growth
affects blood flow
affects metalbolism
affects the brain

Question 24

what are natural killer cells (NK)

Answer 24

• found in blood and lymph
• part of both innate and
  adaptive immune systems
• do not ingest target cell
• bind to cell to induce cellular changes leading
  to apoptosis

Question 25

what are the 2 types of receptors on NK cell membranes

Answer 25

- killer inhibitory receptor (KIR) - killer-activating receptor (KAR)

Question 26

what is Adaptive Acquired Immunity

Answer 26

B lymphocytes and T lymphocytes are programmed to remember and to respond only to specific pathogens

Question 27

B Lymphocytes characteristics

Answer 27

- formed in the bone marrow - programmed to secrete a specific antibody immunoglobulin (Ig) - migrate to lymph nodes and spleen - precursors are the thymocytes - enter bloodstream as T cells

Question 28

what are Memory Cells

Answer 28

- clones of T cells and B cells that have been activated in an immune response - stay in lymph nodes or circulate in blood

Question 29

IgM characteristics

Answer 29

- the largest antibody - temporary - produced when animal is first exposed to an antigen

Question 30

IgG characteristics

Answer 30

- smallest and most common - produced and released by plasma cells bacterial and viral infections - indicative of a chronic infection - can produce passive immunity to fetus

Question 31

IgA characteristics

Answer 31

- protects body surfaces from foreign substances mucosal surfaces (intestinal tract and lungs)

Question 32

IgE characterisitics

Answer 32

- binds to allergens and triggers histamine release from mast cells and basophils - protects against parasitic helminth infections

Question 33

IgD characteristics

Answer 33

activates basophils and mast cells

Question 34

what is cell mediated immunity

Answer 34

- controlled by T cells - does not depend on antibody production - provides immunity against intracellular pathogens - T cells attach directly to antigen markers on surfaces of phagocytes that have already processed the pathogen - cannot recognize antigens on their own - first stimulated by APC cell

Question 35

what Cells Formed from Sensitized T Cells

Answer 35

1. memory cells 2. helper cells (TH ) - help immune system by secreting cytokines 3. cytotoxic T cells (TC) - also known as effector cells, killer cells, killer T cells - attach to antigenic markers on cells and destroy those cells 4. regulatory T cells (TS) - inhibit helper T cell and cytotoxic T cell function - prevent B cells from transforming into plasma cells

Question 36

what is active immunity

Answer 36

the result of an active immune process ⚪ natural immunity ⚪ vaccines: modified live (attenuated), killed virus

Question 37

what is passive immunity

Answer 37

1. receiving antibodies from an external source ⚪maternal antibodies across the placenta via colostrum 2. offers protection ⚪ no activation of immune system 3. protection lost once antibodies disappear from the animal’s system

Question 38

what are Factors in Determining Likelihood of Disease

Answer 38

1 exposure 2 mode of infection/transmission 3 virulence 4 immune system strength 5 resistance ⚪ acquired resistance exposure or vaccination ⚪ species resistance

Question 39

what is Hypersensitivity Reaction

Answer 39

an overreaction of the immune system

Question 40

what is hypersensitivity type 1

Answer 40

- animal is sensitized - antigens bind to IgE antibodies - second exposure to same antigen is severe - fatal without immediate medical intervention

Question 41

what is type 2 hypersensitivity

Answer 41

- occurs when infection is present - immune system is cause of the disease, rather than the cure - cross-reactive antibodies form - body’s own cells are destroyed

Question 42

what is type 3 hypersensitivity

Answer 42

- antibody and antigen form an immune complex - trapped in small blood vessels - activated complement cascade sends chemicals to site - tissue is damaged

Question 43

what is type 4 hypersensitivity

Answer 43

- cell-mediated reactions - systemic inflammatory response syndrome (SIRS)