Ch 12

Question 1

1st line of defense is?

Answer 1

Innate, non-specific
- skin
- mucosa

Question 2

2nd line of defense is ?

Answer 2

innate, non-specific
- phagocytes
- inflammation
- fever
- antimicrobial substances

Question 3

3rd line of defense is?

Answer 3

acquired, specific
- specialized lymphocytes (B & T cells)
- antibodies

Question 4

Function of barriers in the first line of defense and what are they?

Answer 4

impede the entry of microbes/foreign agents, living or non-living
-physical
-chemical
-genetic

Question 5

skin functions

Answer 5

• stratum corneum = tough outer layer impervious/waterproof
• epidermis continually sloughing off along with microorganisms
• high salt content
• fatty acids in sweat are antimicrobial

Question 6

normal flora

Answer 6

humane microbiome, block access of pathogens by competing for nutrients

Question 7

area of the body that have pH that discourages pathogens

Answer 7

-Mucus membrane: sticky and antimicrobial block entry of microbes
-Eyes: lacrimation flush eye surface with tears
-Respiratory: cilitated epithelium (ciliary escalator) moves microbes towards pharynx for removal
-Urogenital: voiding flushes urethra

Question 8

why is normal flora important in certain body sites

Answer 8

normal flora blocks access of pathogens to epithelial surfaces and can create unfavorable environment by competing for nutrients and altering pH

Question 9

Immunology

Answer 9

-study of the body’s 2nd/3rd lines of defense
-body’s response to infectious agents
-allergies and cancer

Question 10

job of the immune system

Answer 10

search, recognize, and destroy pathogens

Question 11

Reticulum

Answer 11

network of connective tissue fibers surrounding all organs

Question 12

where do immune cells mature/form

Answer 12

thymus and bone marrow

Question 12

Reticuloendothelial system

Answer 12

provides passageway within/between tissues and organs
-thymus
-lymph nodes
-tonsils
-spleen
-lymphoid tissue of the mucosa of the gut and respiratory tract

Question 12

Secondary organs/nodes

Answer 12

where immune cells meet pathogens in circulation
-tonsils
-adenoids
-spleen
-peyers patch of small intestine and appendix

Question 13

Granulocytes

Answer 13

have granular cytoplasm and irregular lobed nuclei
-neutrophil, basophil and esinophil

Question 13

Leukocytes

Answer 13

white blood cells produced in bone marrow

Question 14

Neutrophil

Answer 14

-50-70% WBC
-avid phagocyte
-release lysozyme upon death, which damages surrounding tissues
-pus is form of infection (composed of dead and dying neutrophils)

Question 14

Eosinophils

Answer 14

1-5% of WBC with red-stained granules (eosin dye)
-increase in circulation during allergic reactions
-increase in percentage during parasitic infections (cytotoxins)

Question 15

Basophils

Answer 15

0-1% of WBC
-blue-stained granules (methylene blue)
-releases histamine (initiating inflammatory response)
-when they migrate into tissue called mast cells

Question 16

Agranulocyte

Answer 16

dont have visible granules in the cytoplasm “rounder nuclei”
-monocyte (2-8%)
-lymphocyte (20-30%)

Question 17

Monocytes

Answer 17

-avid phagocytes
-engulf microorganisms and larger particles of debris
-when they migrate into tissue called macrophages

Question 18

Lymphocytes

Answer 18

-found in blood and lymphoid tissues (lymph nodes, spleen, thymus, and tonsils)
-natural killer cells (destroy virus/abnormal cells)
-B & T lymphocytes involved in acquired immunity

Question 19

Professional phagocytes

Answer 19

neutrophils, monocyte, and macrophages

Question 20

Phagocyte

Answer 20

“eating cells”

Question 21

Phagocytosis

Answer 21

-physical engulfment
-attack/dismantle foreign cells
-can be isolated event or part of orchestrated events of inflammation

Question 22

Events of phagocytosis

Answer 22

Chemotaxis- phagocytes are attracted by and move toward variety of cytokines generated
Recognition- adherence of the antigen to the cell membrane of the phagocytic cells via PAMPS
Ingestion- pseudopod-like appendages ingest (endocytosis) material within phagosome
Phagolysosome Formation- phagosome moves towards cell interior and fuses with lysosomes
Destruction- lysosomes destroy microorganisms via lysozyme and cytotoxic substances
Excretion- digested contents of phagolysosome are eliminated via exocytosis