Lecture 1

Question 1

what is innate immunity?

Answer 1

non-specific

Question 2

what is adaptive immunity?

Answer 2

specific

Question 3

what are the primary lymphoid organs?

Answer 3

thymus, bone marrow

Question 4

what are the secondary lymphoid organs?

Answer 4

where the lymph nodes are activated e.g. lymph nodes, spleen, tonsils, payers patches

Question 5

what are the tertiary lymphoid organs?

Answer 5

abnormal lymph node-like structures in peripheral tissues at sites of chronic inflammation

Question 6

what do T cells start of as?

Answer 6

thymocytes

Question 7

what happens when thymocytes proliferate?

Answer 7

96-99% die in the cortex and the rest move to the medulla

Question 8

what gives receptor diversity in the thymus?

Answer 8

gene rearrangements

Question 9

what are lymph nodes?

Answer 9

a network of phagocytotic and dendritic cells

Question 10

what is the function of the spleen?

Answer 10

filters antigens from the blood

Question 11

what could happen as a result of having no spleen?

Answer 11

sepsis

Question 12

what are the functions of the skin that help protect from infection?

Answer 12

stratum corneum, glandular secretions, sebaceous layer, commensal bacteria

Question 13

what is the stratum corneum?

Answer 13

outer layer of flat cells filled with keratin, acting as a physical barrier to invasion, abrasion and dehydration

Question 14

how do glandular secretions work?

Answer 14

sweat glands produce lysozyme which degrades peptidoglycans

Question 15

how does sebaceous surfaces work?

Answer 15

glands produce sebum containing unsaturated fatty acids

Question 16

how do commensal bacteria work?

Answer 16

suppress virulent bacteria

Question 17

in what areas do mucous membranes work?

Answer 17

tracts, mucus, cilia

Question 18

how do tracts prevent against infection?

Answer 18

lined with mucous membranes to protect against microbes

Question 19

how does mucous prevent against infection?

Answer 19

has mucins which are long branched carbohydrates which are highly viscous and trap foreign bodies

Question 20

how do cilia protect against infection?

Answer 20

in upper respiratory tract and use synchronised sweeping to move microbes

Question 21

what do lactoferrin do?

Answer 21

binds to iron so bacteria cannot use it for growth

Question 22

what are commensals?

Answer 22

non-pathogenic bacteria

Question 23

how do commensals fight pathogens?

Answer 23

prevent attachment, compete for nutrients, release antibacterial substances such as colicins

Question 24

what are the types of phagocytotic cell?

Answer 24

granulocytes and macrophages

Question 25

what are neutrophils?

Answer 25

polymorphonuclear cell, most common, first to the site of injury, short lived

Question 26

what does polymorphonuclear mean?

Answer 26

having a nucleus with several lobes

Question 27

what are monocytes?

Answer 27

they travel around the bidy and develop into macrophages

Question 28

what are the two types of macrophages?

Answer 28

wandering and fixed

Question 29

what are wandering macrophages?

Answer 29

travel as monocytes, carry out chemotaxis during inflammation

Question 30

what are fixed macrophages?

Answer 30

in lymph nodes, spleen and most organs and are long lived

Question 31

what are the oxygen independent killing mechanisms?

Answer 31

lysozymes, catonic proteins, defensins, tumour necrosis factor

Question 32

how do lysozymes kill bacteria?

Answer 32

degrade cell wall

Question 33

what do catonic proteins do?

Answer 33

cause the pH to fall

Question 34

what do defensins do?

Answer 34

form pores in the bacterial membrane

Question 35

what does TNF do?

Answer 35

increases inflammation and phagocytosis