Exam 4

Question 1

skin and mucosal surfaces

Answer 1

organism must penetrate, adhere, grow
mucus limits direct access to epithelial cells

Question 2

normal flora

Answer 2

young are more susceptible before stable adult flora develops
diet and drugs can alter flora

Question 3

antimicrobial secretions

Answer 3

lysozyme & other enzymes kill bacteria in saliva and tears
defensin proteins insert in microbial membranes
blood proteins sequester nutrients
fatty acids on skin lower pH

Question 4

physical removal

Answer 4

cilia/mucus movement
urine flushing

Question 5

general host defenses

Answer 5

skin and mucosal surfaces, normal flora, antimicrobial secretions, physical removal, stomach acid

Question 6

components of the immune system (2nd and 3rd line of defense)

Answer 6

blood and lymph systems, organs and tissues, blood cells, plasma proteins

Question 7

blood and lymph systems

Answer 7

two interconnected circulatory systems
- blood is closed loop powered by heart
- lymph is a drainage system returning tissue to blood

Question 8

lymph drainage system

Answer 8

• series of connecting vessels starting with microscopic capillaries
• fluid drains from lymph to surrounding tissue
• movement of fluid powered by skeletal muscle pressing on lymph vessel (one way valves keep lymph moving to chest)
• white blood cells move in and out of lymph vessels (extravasation), WBCs collect in lymph nodes, kill bacteria, remove debris, and interact with other cells of the immune system present there

Question 9

primary organs/tissues

Answer 9

where lymphocytes develop: thymus and bone marros

Question 10

secondary organs/tissues

Answer 10

where lymphocytes collect: spleen, lymph nodes, tonsils, adenoids, appendix (MALT GALT SALT)
M cells in skin, tonsils, adenoids, intestines monitor flora

Question 11

blood cells: erythrocytes

Answer 11

red blood cells, not part of immune system (enucleated, carry oxygen)

Question 12

platelets

Answer 12

involved in clotting

Question 13

leukocytes: white blood cells

Answer 13

monocytes, dendritic cells, macrophages, polymorphonuclear leukocytes, mast cells, lymphocytes

Question 14

monocytes, dendritic cells, macrophages

Answer 14

these are phagocytic, antigen presenting cells
-engulfs foreign cells, viruses, proteins
-break these down and display foreign peptides on their surface
-monocytes circulate in blood
-dendritic cells and macrophages attach to different tissues

Question 15

polymorphonuclear leukocytes (PNMs or granulocytes in blood)

Answer 15

neutrophils, eosinophils, basophils

Question 16

PNMs: neutrophils

Answer 16

phagocytic cells, migrate to site of infection (go where they are needed) can use NET (neutrophil extracellular trap) to kill cells

Question 17

PNMs: eosinophils

Answer 17

anti-protozoan secretions

Question 18

PNMs: basophils

Answer 18

inflammation mediator

Question 19

mast cells

Answer 19

mediate inflammation throughout the body, not in blood

Question 20

lymphocytes

Answer 20

mostly in spleen and lymph nodes:
natural killer cells, T cells, B cells

Question 21

lymphocytes: T cells

Answer 21

central to adaptive immunity

Question 22

lymphocytes: B cells

Answer 22

part of adaptive immunity, produce antibodies

Question 23

lymphocytes: natural killer cells

Answer 23

kill infected or cancerous cells

Question 24

proportion of blood

Answer 24

plasma proteins (soluble in fluid portion of blood): 55%
blood cells: 45%

Question 25

plasma proteins

Answer 25

fibrinogen - clotting antibodies complementary iron sequestration and other antibacterial proteins

Question 26

response: infection via a splinter

Answer 26

resident macrophages engulf pathogens and release cytokines. vasoactive factors and cytokines help deliver additional phagocytes. some cytokines initiate healing as pathogens are destroyed.

Question 27

inflammatory response

Answer 27

a non specific response to wounds and infection, signs describes 2000 years ago: redness, heat, pain, swelling

Question 28

detection

Answer 28

triggered by unique signals of invader, bind to toll like receptors (in membrane) or nod-like receptors (in cytoplasm), cause transcription, and release of cytokines

Question 29

clotting

Answer 29

clotting factors released by platelets, attempt to contain (wall off) infection

Question 30

phagocytosis

Answer 30

1. bacterium binds to the surface of a phagocytic cell. antibody or complement can aid binding 2. phagocyte pseudopods extend and engulf the organism 3. invagination of phagocyte membrane traps the organism within a phagosome 4. lysosome fuses and deposits enzymes into the phagosome. enzymes cleave macromolecules and generate reactive oxygen species, destroying the organism

Question 31

phagocyte/macrophage engulfs the microbe

Answer 31

invader is recognized because it does not have self antigen (CD4), some pathogens can avoid because of their capsule. antibodies can increase phagocytosis