Lecture 30

Question 1

What is the immune system composed of?

Answer 1

Organs, cells and molecules

Question 2

What is the immune system?

Answer 2

An organised system of organs, cells and molecules that interact together to defend the body against disease

Question 3

What are some examples of diseases affected by the immune response?

Answer 3

Cancer, inflammatory diseases and infectious diseases

Question 4

What are some examples of inflammatory diseases?

Answer 4

Arthritis, allergy/asthma, lupus, diabetes, Crohn’s disease/ inflammatory bowel disease, multiple sclerosis

Question 5

What are some examples of infectious diseases?

Answer 5

HIV/ AIDS, tuberculosis, influenza and malaria

Question 6

What are microbes?

Answer 6

Viruses, bacteria, fungi and protozoa

Question 7

What are the primary organs used for?

Answer 7

Production of white blood cells

Question 8

What are the secondary organs used for?

Answer 8

Sites where immune responses are initiated

Question 9

What are the primary lymphoid organs?

Answer 9

Bone marrow and thymus

Question 10

What is bone marrow the source of?

Answer 10

The source of stem cells that develop into cell of the innate and adaptive immune responses

Question 11

What does the thymus do?

Answer 11

Its a “school” for white blood cells called T cells, developing T cells learn to not react to self

Question 12

What are the secondary lymphoid organs?

Answer 12

Spleen, lymph nodes

Question 13

What do lymph nodes do?

Answer 13

Located along the lymphatic vessels, lymph fluid from blood and tissue if filtered, the site of initiation of immune responses

Question 14

What does the spleen do?

Answer 14

Site of initiation for immune responses against blood-borne pathogens

Question 15

How many layers of defense does the immune system have?

Answer 15

3

Question 16

What is the first layer of defense?

Answer 16

Chemical and physical barriers

Question 17

What is the second layer of defense?

Answer 17

The innate ‘arm’

Question 18

What is the third layer of defense?

Answer 18

Adaptive ‘arm’

Question 19

What are the chemical and physical barriers?

Answer 19

Skin and mucosal surfaces, organisms can get in from cuts, things that cut the skin.

Question 20

What are the two layers of skin?

Answer 20

Epidermis and dermis

Question 21

What is the epidermis made up of?

Answer 21

Dead cells, keratin and phagocytic immune cells

Question 22

What is the dermis made up of?

Answer 22

Thick layer of connective tissue, collagen and blood vessels and phagocytic immune cells.

Question 23

Why is it good to have dead cells on the skin?

Answer 23

Any microbes or organisms get flushed away as dead skin falls off all throughout the day.

Question 24

Where are dendritic cells found? and what do they do?

Answer 24

In the lower level of the epidermis, where they recognise bacteria for a fast responses.

Question 25

What is the chemical defense of the skin?

Answer 25

Antimicrobial peptides e.g pores in microbial cell membranes Lysozyme breaks down bacterial cell walls Sebum: low pH Salt: hypertonic

Question 26

What is the mucous membrane and what is it made up of?

Answer 26

1-2 layers | Epithelium: tightly packed live cells, constantly renewed, mucus-producing goblet cells

Question 27

What systems are the mucosal membrane cells in?

Answer 27

Ocular, respiratory, oral and urogenital/ rectal

Question 28

What is the mucociliary escalator?

Answer 28

Cilia move the mucus up to the pharynx

Question 29

What are other mucosal surface chemical defenses?

Answer 29

``` Stomach has low pH Gall bladder- Bile Intestine- digestive enzymes Mucus Defensins Lysozyme (tears, urine) ```

Question 30

What are the innate defenses?

Answer 30

Surface barriers and internal defenses

Question 31

What does the surface barriers consist of?

Answer 31

Skin and mucous membranes

Question 32

What does the internal defenses consist of?

Answer 32

``` Phagocytes Natural killer cells Inflammation Antimicrobial proteins Fever ```

Question 33

What are some adaptive defenses?

Answer 33

Humoral immunity and cellular immunity

Question 34

What makes up the humoral immunity?

Answer 34

B cells

Question 35

What makes up the cellular immunity?

Answer 35

T cells

Question 36

How fast does the innate immunity respond?

Answer 36

Rapid (hours)

Question 37

How fast does the adaptive immunity respond?

Answer 37

Slow (days to weeks)

Question 38

What is the difference between innate and adaptive immunity?

Answer 38

- Innate immunity is already in place, its rapid, fixed, limited specificities na has no specific memory where as: - Adaptive immunity improves during the response, its very slow, variable, highly specific and has long term specific memory

Question 39

What does it mean by limited specificities in innate immunity?

Answer 39

Detects molecular components shared by many pathogens

Question 40

What does it mean by highly specific in adaptive immunity?

Answer 40

Detects molecular components specific to individual pathogens