L27 - intro to immunology

Question 1

what is the immune system?

Answer 1

• prevents/ limits infection
• complex network of cells, organs, proteins, tissues that defend body from pathogens
• recognise pathogens
• recognises abnormal cells (cancer cells)

Question 2

components of immune system

Answer 2

• organs and cells
• lymph system
• circulatory system

Question 3

2 types of immunity

Answer 3

1. innate: non specific
2. acquired/adaptive: specific

Question 4

what is innate immunity?

Answer 4

• aka natural immunity
• non-specific defence mechanism
• initial response to remove microbes and prevent infection
• fast response (mins to hrs)

Question 5

functions of innate immunity

Question 6

components of innate/ natural immunity

Answer 6

1. physical barriers: mucous lining in nose
2. chemical barriers: stomach acid
3. protective cells: NK cells, WBC that destroy invaders
4. sneezing, coughing, vomiting

Question 7

examples of physical and chemical barriers

Answer 7

1. skin, hair, cilia
2. mucous membrane
3. tears
4. mucus and chemical secretions
5. digestive enzymes in mouth
6. stomach acid
7. blood brain barrier

Question 9

how are macrophages, neutrophils and mast cells involved in innate immunity?

Answer 9

remove pathogens by phagocytosis

Question 10

how are natural killer (NK) cells involved in innate immunity?

Answer 10

eliminate infected or abnormal host cells

Question 11

how are dendritic cells involved in innate immunity?

Answer 11

• direct microbial activity
• secrete chemicals that can recruit and activate other immune cells

Question 12

what causes inflammation?

Answer 12

• physical barrier is breached
• infection

Question 13

what inflammation do?

Answer 13

• eliminates pathogens and promotes tissue repair
• releases signalling molecules (cytokines & chemokines)
• recruits immune cells to site of infection
• causes heat, pain, redness, swelling

Question 14

what is the complement system?

Answer 14

• 30 diff plasma proteins
• made in liver
• but circulates in the blood
• helps destroy pathogens
• immune cell activation
• clearance of immune complexes
• activated through different pathways
• bridge between innate + adaptive immunity

Question 15

what is adaptive/aquired immunity?

Answer 15

• specific
• target defence mechanism
• initiated when innate response fails to clear pathogen
• detects antigens on pathogen
• adapts to recognise and remember specific pathogens
• long lasting protection
• slow response

Question 16

2 types of adaptive immunity

Answer 16

• cellular
• humoral

Question 17

function of the adaptive immune system

Question 18

dendritic cells and cell mediated immunity

Answer 18

dendritic cells present antigen to T cells to trigger a response of antigen (diff types of T cells)

Question 19

what is a cytotoxic T cell in cell mediated immunity?

Answer 19

they directly attack and kill infected/ abnormal cells

Question 20

helper T cells in cell mediated immunity

Answer 20

assist B cells in antibody production and activate other immune cells

Question 21

regulatory T cells in cell mediated immunity

Answer 21

help maintain immune balance and prevent excessive responses