Immunity

Question 1

What are the types of immunity?

Answer 1

Innate or nonspecific

Adaptive or specific

Question 2

Describe the innate immune system

Answer 2

Non-specific defence, present at birth. Has no memory. Provides immediate protection

Question 3

What defences are included in the innate immune system?

Answer 3

Physical - skin, saliva, tears, mucous, etc.
Chemical mediators - histamine, cytokines
White blood cells
Inflammation
Fever

Question 4

Describe the adaptive immune system

Answer 4

Specific, has memory, acquired over lifetime. Employed when innate system is over-worked.

Question 5

What defences are included in the adaptive immune system?

Answer 5

Cell-mediated immunity

Anti-body mediated immunity.

Question 6

Describe cell-mediated immunity

Answer 6

T lymphocytes (helper t cells and cytotoxic t cells)
Activated by a specific antigen
Specific "clones" bind to antigen
Co-stimulation required (helper t cells)
Activated cytotoxic t cells divide

Question 7

Describe antibody-mediated immunity

Answer 7

B cells
Phagocytosis of an extracellular pathogen that matches the specific B cell receptor on that B cell
Requires co-stimulation
B cells divide to form plasma cells that make antibodies and memory cells

Question 8

Define natural active immunity

Answer 8

Antigens are introduced through natural exposure

Question 9

Define artificial active immunity

Answer 9

Antigens are deliberately introduced in a vaccine

Question 10

Define natural passive immunity

Answer 10

Antibodies from the mother are transferred to her child across the placenta or in milk.

Question 11

Define artificial passive immunity

Answer 11

Antibodies produced by another person or an animal are injected.