lecture exam 4

Question 1

what is immunology

Answer 1

study of all biological, chemical and physical events surrounding the function of the immune system. the immune system is all over every organ, tissue and fluids.

Question 2

what does innate, natural, nonspecific immunity include?

Answer 2

this is the 1st line of defense and it includes any barrier that blocks invasion at the portal of entry (skin and mucosal membranes), chemicals, cellular and protective cells and fluids.

Question 3

what does the second line of defense include?

Answer 3

phagocytosis, complement, and inflammation

Question 4

what are some physical defenses?

Answer 4

cellular barriers, mechanical defenses and microbiome

Question 5

acquired, adaptive, or specific immunity includes:

Answer 5

this is the 3rd line of defense. it includes exposure to foreign substance and production of protective antibodies and memory cells

Question 6

cellular barriers come in 3 different ways. explain them

Answer 6

skin barrier- great barrier to prevent entry of most microbes; epidermis, dermis, hypodermis; infections occur when skin is compromised

mucous membranes- lines the respiratory, urinary and digestive tracts; layer of epithelial cells connected by tight junctions and covered by a layer of mucus; mucus traps microbes, contain antimicrobial peptides

endothelium- epithelial cells that line the blood vessels and lymphatic vessels; effective; blood-brain barrier protects CNS

Question 7

describe mechanical defenses

Answer 7

goal is to remove pathogens from body before they take up residence in the body; shedding of skin cells, sweat, mucociliary escalator (respiratory tract), going #1 &2, peristalsis (muscle contractions remove sloughed mucus/trapped microbes), sneezing/cough, blinking

Question 8

describe microbiome

Answer 8

resident microbiota compete for space/nutrition in the skin/upper respiratory tract, GI tract, GU tract with invading pathogens

some produce microbial antagonism- prevents pathogens from growing

Question 9

chemical defenses include

Answer 9

chemical and enzymatic mediators, plasma protein mediators, cytokines and inflammation- eliciting mediators

Question 10

what is a chemical defense that is produced by the skin and how does it provide protection against pathogens

Answer 10

oil (sebum)- produced by sebaceous glands

seals off hair follicles and prevents bacteria from invading sweat glands and tissues

Question 11

name the digestive tract’s chemical and enzymatic mediators found in bodily fluid

Answer 11

oral cavity- saliva contains lactoperoxidase
esophagus- mucous contains lysozyme
stomach- HCI causes high acidity
lower digestive tract- pancreatic/intestinal enzymes, bile, paneth cells produce lysozyme

Question 12

chemical and enzymatic mediators
urinary tract-
female rep. sys.-
eyes-
ears-
respiratory tract

Answer 12

urinary tract- urine slightly acidic pH 6

female rep. sys.- lactobacillus produces lactic acid to make pH lower (exogenous mediator)

eyes- tears contain lysozyme (acts of peptidoglycan) and lactoferrin (binds iron)

ears-cerumen traps bacteria and contains fatty acids

respiratory tract- contain lysozyme, lactoferrin, lactoperoxidase

Question 13

proteins that protect the blood against microbes are

Answer 13

complement proteins and cytokines

Question 14

what is the complement system?

Answer 14

*group of plasma protein mediators that connect the innate and adaptive immunity
*30 proteins (c1-c9)
*activated by microbes, antibodies, mannose-binding lectin by 3 ways
* provide the same protective outcomes- opsonization, inflammation, chemotaxis, and cytolysis

Question 15

what is the function of the complement system?

Answer 15

*opsonization- coating of pathogen by a chemical substance: allows phagocytic cell to recognize, engulf, and destroy
*include C3b, antibodies, mannose-binding protein
*inflammation is triggered by C5a which calls chemotaxis, neutrophils and macrophages to the area
*cytolysis-MAC composed of C6,C7,C8 &C9; forms pores in membrane of gram-

Question 16

what is cytokines?

Answer 16

*soluble protein act as communication signals b/w cells
*cause cell proliferation, cell differentiation, inhibition of cell division, apoptosis, and chemotaxis
*bind to target receptor of cell to act as autocrine, paracrine or endocrine fashion
*two most important: interlukins and interferons

Question 17

desrcibe interlukins (boss lady) and interferons (chismosos)

Answer 17

interlukins- modulates almost every function of the immune system

interferons- produced by cells when infected with viruses and alert immune system that there is a virus infection; stimulates nerby cells to prevent virus replication inside them; stimulate immune system to attack virus infected cells

Question 18

describe the chemical mediator: inflammation-eliciting meditator

Answer 18

contribute to inflammation/fever

Question 19

what is histamine

Answer 19

chemical mediators that is released from mast cells and basophils to promote vasodilation, bronchoconstriction, contraction of smooth muscles, increased mucus secretion

Question 20

what is prostaglandis? what does it cause?

Answer 20

chemical mediators that promotes inflammation and fever

Question 21

what is Bradykinin and what does it do?

Answer 21

chemical mediator that increases vasodilation and vascular permeability to cause edema

Question 22

what are cellular defenses?

Answer 22

erythrocytes- carry oxygen
thrombocytes- clot formation/platelets
leukocytes- wbc

Question 23

what is hematopoiesis

Answer 23

formation of blood with formed elements

Question 24

neutrophils, eosinophils, basophils, or mast cells are_____

Answer 24

granulocytes

Question 25

B lymphocytes and T lymphocytes, natural killer cells, monocytes are_____

Answer 25

agranulocytes

Question 26

what are neutrophils?

Answer 26

*main role: phagocytosis’ go through walls of blood vessels when “called” for inflammation
*degranulation: defensins and hydrolytic enzymes release toxic molecules to surrounding tissue to kill bacteria
*neutrophil extracellular traps (NETs) form a net to trap pathogens to kill them

Question 27

what are eosinophils?

Answer 27

*role in phagocytosis
*effective against protozoa and helminths
*allergic reactions
*granules contain histamine

Question 28

what are basophils?

Answer 28

*involved in inflammation and allergic reaction
*granules contain histamine
*degranulation is activated by complement

Question 29

what are mast cells?

Answer 29

*functionally similar to basophils
*bound to connective tissue around blood vessels

Question 30

B & T lymphocytes are involved in ____

Answer 30

specific adaptive immune respomse

Question 31

whar are Natural Killer cells?

Answer 31

*type of T cells involved in nonspecific innate defenses
*recognize/destroy any abnormal cells
*destroy by secreting
*perforins which creat a pore in the target cell
*granzymes enter pores/triggers cell to die by apoptosis

Question 32

what are monocytes?

Answer 32

*when they leave the bloodstream, they differentiate into a macrophage/dendritic cell
*macrophages reside in body tissues for long time
*dendritic cells reside in skin and mucous membranes
*major role in phagocytosis

Question 33

what is phagocytosis? what is the function?

Answer 33

*seek, ingest, kill pathogens
*phagocytes circulate bloodstream/ability to leave squeezing out endothelial cells of capillaries called diapedesis (or extravasation)
*initiated by chemotactic factors: Ca5 & other cytokines released by tissue cells and macrophages

Question 34

describe phagocytic recognition

Answer 34

*phagocytes recognize pathogen molecular structures called pathogen-associated molecular patters or PAMPs
*using patterns recognition receptors (PRRs), the phagocytes will bind to the PAMPs
*this triggers the phagocyte to engulf the pathogen

Question 35

what is inflammation?

Answer 35

*triggered by a cascade of chemical mediators and cellular responses that occure when cells are damages/stressed and when pathogens breach teh physical barriers of the innate immune system
*allows recruitment of cellular defenses needed to elimate pathogens, remove damaged and dead cells, initiate repair mechanism

Question 36

steps of acute inflammation

Answer 36

1. vasoconstriction of blood vessels will occur to minimize blood loss
2. vasodilation/increased vascular permeability happens due to release of histamine by mast cells; 5 signs: erythema, edema, pain, hear, altered function. this causes…
3. influx of phagocytes at site of injury, diapedesis, neutrophils arrive first, phagocytes contribute to inflammatory response, complemetn sysrem is activated, pus forms
4. macrophages arrive second to clean up

Question 37

what is fever

Answer 37

*inflammatory respone
*inhbits multiplication of heat sensitive microbes
*prevents nutrition of bacteria by reducing the availability of iron
*enhances the innate immune defenses

Question 38

what regulates the body temperature

Answer 38

hypothalamus

Question 39

primary lymphoid organs

Answer 39

site of lymphocytic origin and maturation
*bone marrow- site of all blood cell formation;site of B-cell maturation
*thymus- high rate of growth & activity until puberty, then begins to skrink; T cell maturation site

Question 40

secondary lymphoid organs and tissues

Answer 40

spleen and lymph nodes
cells distributed throughout body tissues- skin and mucous membranes
*lymph nodes-small, encapsulated, bean-shaped organs along lymphatic channels/large blood vessels of the thoracic/abdominal cavities
*spleen- similar to lymph node, filters circulating blood to remove worn out RBCs and pathogens; miscellaneous: Peyer’s patch, SALT, MALT, BALT, NALT, tonsils