Which of the following is a barrier against pathogens provided by the skin?

1. high pH
2. mucus
3. tears
4. desiccation

Although interferons have several effects, they are particularly useful against infections with which type of pathogen?

1. bacteria
2. viruses
3. fungi
4. helminths

Which organelle do phagocytes use to digest engulfed particles?

1. lysosome
2. nucleus
3. endoplasmic reticulum
4. mitochondria

Which innate immune system component uses MHC I molecules directly in its defense strategy?

1. macrophages
2. neutrophils
3. NK cells
4. interferon

Which of the following is both a phagocyte and an antigen-presenting cell?

1. NK cell
2. eosinophil
3. neutrophil
4. macrophage

Which immune cells bind MHC molecules on APCs via CD8 coreceptors on their cell surfaces?

1. T_H cells
2. CTLs
3. mast cells
4. basophils

What “self” pattern is identified by NK cells?

1. altered self
2. missing self
3. normal self
4. non-self

The acquired ability to prevent an unnecessary or destructive immune reaction to a harmless foreign particle, such as a food protein, is called ________.

1. the T_H2 response
2. allergy
3. immune tolerance
4. autoimmunity

Upon reexposure to a pathogen, a memory B cell can differentiate to which cell type?

1. CTL
2. naïve B cell
3. memory T cell
4. plasma cell

Foreign particles circulating in the blood are filtered by the ________.

1. spleen
2. lymph nodes
3. MALT
4. lymph

The structure of an antibody is similar to the extracellular component of which receptor?

1. MHC I
2. MHC II
3. BCR
4. none of the above

The first antibody class to appear in the serum in response to a newly encountered pathogen is ________.

1. IgM
2. IgA
3. IgG
4. IgE

What is the most abundant antibody class detected in the serum upon reexposure to a pathogen or in reaction to a vaccine?

1. IgM
2. IgA
3. IgG
4. IgE

Breastfed infants typically are resistant to disease because of ________.

1. active immunity
2. passive immunity
3. immune tolerance
4. immune memory

Allergy to pollen is classified as:

1. an autoimmune reaction
2. immunodeficiency
3. delayed hypersensitivity
4. immediate hypersensitivity

A potential cause of acquired autoimmunity is ________.

1. tissue hypersensitivity
2. molecular mimicry
3. histamine release
4. radiation exposure

Autoantibodies are probably involved in:

1. reactions to poison ivy
2. pollen allergies
3. systemic lupus erythematosus
4. HIV/AIDS

Which of the following diseases is not due to autoimmunity?

1. rheumatic fever
2. systemic lupus erythematosus
3. diabetes mellitus
4. HIV/AIDS