Unit 5: Immunity

Question 1

active immunity

Answer 1

defenses that arise when a pathogen infects the body and prompts a primary or secondary immune response

Question 2

passive immunity

Answer 2

passed from mother to fetus

• IgG in blood provide guard against pathogens that have never infected newborn
• IgA transferred in breast milk, provide immunity to digestive tract and protect mucous membranes

Question 3

immunization

Answer 3

• active

- antigens introduces into body, inducing primary immune response and immunological memory

Question 4

artificial passive immunization

Answer 4

antibodies from an immune animal are injected into a non-immune animal

Question 5

Allergies

Answer 5

• exaggerated response
  1. IgE antibodies (produced after initial exposure) bind to receptors on mast cells
  2. On second exposure, IgE molecules bind to allergen
  3. Cross linking of IgEs triggers release of histamine and other chemicals leading to allergy symptoms

Question 6

anaphylactic shock

Answer 6

after allergen exposure, widespread release of mast cell contents trigger dilation of peripheral blood vessels
-causes blood pleasure to drop and constriction of bronchides

Question 7

Antigenic Variation

Answer 7

• changes in epitope expression

- an alteration in how a pathogen appears to immune system can allow pathogen to avoid a secondary response

Question 8

Latency

Answer 8

-virus may enter a largely inactive state

Question 9

HIV

Answer 9

• infects helper T cells, loss makes body more prone to serious infection
• mutates at a very high rate
• product DNA is integrated into host cells, can remain latent and go undetected