lecture 7 - immune system

Question 1

what is the immune system?

Answer 1

body’s defence against infectious organisms and other invaders.
- bacteria tries to make you ill, your immune system tries to fight it

Question 2

what are the functions of the immune system?

Answer 2

protect, recognise, attack and destroy

Question 3

what is innate (natural) immunity?

Answer 3

Response is non-specific
Exposure leads to immediate maximal response
No immunological memory
Found in nearly all forms of life
Activates the acquired arm of the immune system

Question 4

what is acquired (adaptive) immunity?

Answer 4

Pathogen and antigen specific response
Lag time between exposure and maximal response
Exposure leads to immunological memory
Found only in jawed vertebrates

Question 5

what is the main function of a neutrophil?

Answer 5

phagocytosis

Question 6

what is the main function of a eosinophil?

Answer 6

to destroy parasites

Question 7

what is the main function of a basophil?

Answer 7

inflammation

Question 8

what happens during phagocytosis?

Answer 8

eats the cell - engulfs it - eats anything foreign in the body

Question 9

what is the neutrophil function - the killing process (degranulation)?

Answer 9

respiratory burst - reactive o2 species - hydrochloric acid are released onto antigen
commits self suicide - when it performs its killing machinery it dies

Question 10

what is the difference between a monocyte and a macrophage?

Answer 10

mono - in blood, macro - in tissue

Question 11

why is it important a monocyte knows what it is fighting?

Answer 11

it talks to the acquired arm of the immune system

Question 12

where are most lymphocytes found?

Answer 12

acquired arm of the immune system

Question 13

is the innate immune system the first line of defence?

Answer 13

yes

Question 14

what is an antigen presenting cells role?

Answer 14

display/present the invading antigen to the acquired arm of the immune system to activate it

Question 15

what can lymphocytes be broken down to?

Answer 15

t cells and b cells

Question 16

what is a t cell?

Answer 16

Mature in the thymus
60-70% lymphocytes
Cell-mediated (intracellular) response
Produce memory cells

Question 17

what is a b cell?

Answer 17

Mature in the bone marrow
5-15% lymphocytes
Humoral (extracellular) response
Produce memory cells

Question 18

what is a t helper subset?

Answer 18

orchestrates and co-ordinates the immune response

Question 19

what is a t cytotoxic subset?

Answer 19

bind to and kills antigen specific infected cells

Question 20

what is a t regulatory subset?

Answer 20

help to regulate/switch off the immune response to avoid chronic inflammation

Question 21

is a type one helper intracellular or extracellular?

Answer 21

intracellular

Question 22

is a type two helper intracellular or extracellular?

Answer 22

extracellular

Question 23

why is it important to know whether it is a type one or type 2 helper cell?

Answer 23

it will put all its energy into the cell that will kill it - counterbalance and work against it

Question 24

what is humoral immunity?

Answer 24

t helper cells still part of the initial process
t cell signals to the b cell that its a humoral and that it is extracellular - until a t helper cell to say go ahead and kill it
b cells produces an abundance of plasma cell - secretes antibodies which are specific to that particular antigen
the antibodies are specific to the antigen
cant directly kill an antigen - antibodies bind to the receptor sites and so cant bind to anything else - neutralises it

Question 25

what are factors affecting the immune system?

Answer 25

drugs, alcohol, diet, exercise, early life events, smoking etc

Question 26

what system does the immune system work with?

Answer 26

endocrine