Lecture 1

Question 2

Which animals possess an adaptive immune system?

Answer 2

Vertebrates. Invertebrates have an innate immune system only.

Question 3

True or False: The innate immune system responds to specific antigens.

Answer 3

FALSE. The innate immune system is non-specific.

Question 4

Natural Killer (NK) cells belong to which system of immunity?

Answer 4

Innate Immune System.

Question 5

Define PAMPs.

Answer 5

Pathogen-associated molecular patterns. Molecules produced by microbes and not by mammalian cells.

Question 6

Define DAMPs.

Answer 6

Damage-associated molecular patterns. Molecules found within mammalian cells that are released when the cell is damaged or dies.

Question 7

Define “tolerance” in terms of immunity.

Answer 7

An adaptive immune cell will not attack other cells of the body, or “self.”

Question 8

Name the five major components of innate immunity.

Answer 8

1. Epithelial barriers (skin and mucus membranes). 2. Phagocytic and sentinel cells. 3. Complement system. 4. Innate defense cytokines. 5. NK cells.

Question 9

True or False: Only the adaptive immune system has memory.

Answer 9

TRUE

Question 10

Name the two major components of the adaptive immune system.

Answer 10

1. Humoral (antibodies). 2. Cell-mediated immunity (CMI).

Question 11

True or false: B cells mature in the Bursa of Fabricius in mammals.

Answer 11

FALSE. B cells mature in the Bursa of Fabricius in avian species. In mammals, they mature in the bone marrow.

Question 12

Which is the largest antibody class?

Answer 12

IgM, which is a pentamer.

Question 13

Where do T lymphocytes mature?

Answer 13

Thymus.

Question 14

True or false: T cells can only recognize peptides presented on MHC molecules.

Answer 14

TRUE. Unlike B cells that can recognize intact antigens, T cells can only recognize peptides (processed proteins) presented on the major histocompatability complex (MHC).

Question 15

True or false: Antibodies can help fight intracellular infections.

Answer 15

FALSE. Antibodies cannot enter cells.

Question 16

Name the two leukocytes that possess phagocytic abilities.

Answer 16

Macrophages and neutrophils.

Question 17

Name the antibody that is in the highest concentration in the serum.

Answer 17

IgG.

Question 18

A healthy animal is exposed to a pathogen and successfully fights the infection. What will be the result of a second exposure to the same pathogen?

Answer 18

Antibodies against the pathogen will produced in higher concentration and much more rapidly due to immunological memory. First exposure is primary response. Second exposure is secondary response.

Question 19

Where is IgA primarily found?

Answer 19

Mucosal surfaces. Present as a dimer.

Question 20

True or false: IgE is important in allergic reactions

Answer 20

TRUE. Also produced during parasitic infections.

Question 21

Define “autoimmune disease.”

Answer 21

When the adaptive immune system has lost the ability to recognize self, leading to damage to the animal’s own tissues.