The immune system | Practice Problems, Examples & Solutions

Innate Immunity of Invertebrates

25 Practice Problems

00:18

Biochemistry

What is innate immunity? What is acquired immunity?

Viruses, Cancer, and Immunology

00:46

Biology: Concepts and Investigations

List five types of innate defenses.

The Immune System

00:57

Biology Concepts and Applications

Choose the defining characteristics of innate immunity.
a. self/nonself recognition
b. immediate response
c. set of general defenses
d. antigen memory
e. diverse antigen receptors
f. fixed number of PAMPs
g. tailored for specific antigens

Immunity

Innate Immunity of Vertebrates

36 Practice Problems

01:00

Molecular Biology of the Cell

Because a monoclonal antibody recognizes a specific antigenic site (epitope), it binds only to the specific protein against which it was made.

Analyzing Cells, Molecules, and Systems

00:54

Nester's Microbiology: A Human Perspective

Which of the following statements about viruses is false? They may
a) colonize the skin.
b) enter host cells by endocytosis.
c) enter host cells by fusion of the viral envelope with the cell membrane.
d) induce apoptosis in infected host cells.
e) suppress expression of MHC class I molecules on host cells.

Host-Microbe Interactions

02:41

Nester's Microbiology: A Human Perspective

All of the following cell types are found in a granuloma except
a) neutrophils.
b) macrophages.
c) giant cells.
d) T cells.

The Innate Immune Response

Adaptive Immunity and Pathogen-Specific Recognition

63 Practice Problems

01:41

Molecular Biology of the Cell

T cells whose receptors strongly bind a self-peptide-MHC complex are killed off in peripheral lymphoid organs when they encounter the self peptide on an antigen-presenting dendritic cell.

The Innate and Adaptive Immune Systems

01:13

Molecular Biology of the Cell

Hybridoma technology allows one to generate monoclonal antibodies to virtually any protein. Why is it, then, that genetically tagging proteins with epitopes is such a commonly used technique, especially since an epitope tag has the potential to interfere with the function of the protein?

Analyzing Cells, Molecules, and Systems

01:26

Nester's Microbiology: A Human Perspective

Influenza vaccines must be changed yearly because the amino acid sequence of the viral proteins change gradually over time. Based on this information, which is the most logical conclusion? The influenza virus
a) is enveloped
b) is non-enveloped.
c) has a DNA genome.
d) has an RNA genome.
e) causes a persistent infection

Viruses, Viroids, and Prions

Cytotoxic T Cells

48 Practice Problems

06:47

Molecular Biology of the Cell

Before exposure to a foreign antigen, T cells with receptors specific for the antigen are a tiny fraction of the $\mathrm{T}$ cells-on the order of 1 in $10^{5}$ or 1 in $10^{6}$ T cells. After exposure to the antigen, only a small number of dendritic cells typically display the antigen on their surface. How long does it take for such antigen-presenting dendritic cells to interact with the antigen-specific T cells, which is the key first step in $\mathrm{T}$ cell activation and clonal expansion? The dynamics of the search process were examined by labeling dendritic cells red and T cells green, so that contacts in an intact lymph node could be scored visually using two-photon fluorescence microscopy (Figure $Q 24-3$ A). The frequency of contacts between dendritic cells and T cells from such experiments is given in Figure $24-3 B$. Assuming that 100 dendritic cells present the specific antigen, how long would it take them to scan $10^{5}$ T cells? How long for $10^{6} \mathrm{T}$ cells?

The Innate and Adaptive Immune Systems

01:07

Molecular Biology of the Cell

The chemical carcinogen dimethylbenz[a]anthracene (DMBA) must be an extraordinarily specific mutagen since $90 \%$ of the skin tumors it causes have an A-to-T alteration at exactly the same site in the mutant Ras gene.

Cancer

01:16

Introduction to General, Organic and Biochemistry

What is the difference between a T-cell receptor (TcR) and a TcR complex?

Immunochemistry

Humoral and Cell-Mediated Immune Responses

61 Practice Problems

02:05

Nester's Microbiology: A Human Perspective

If the thymus is removed from a 2-year-old child, you might expect which of the following to occur?
a) increased success of an organ transplant and increased incidence of bacterial infection.
b) increased success of an organ transplant and decreased incidence of bacterial infection.
c) decreased success of an organ transplant and increased incidence of viral infection.
d) decreased incidence of cancer and decreased incidence of viral infection.
e) decreased success of an organ transplant and increased incidence of cancer.

Immunologic Disorders

03:21

Nester's Microbiology: A Human Perspective

Which of the following statements about antibodies is false?
a) If you removed the Fc portion, antibodies would no longer be capable of opsonization.
b) If you removed the Fc portion, antibodies would no longer be capable of activating the complement system.
c) If you removed an Fab portion, an antibody would no longer be capable of cross-linking antigen.
d) If IgG were a pentamer, it would bind antigens more efficiently
e) If IgE had longer half-life, it would protect newborn infants.

The Adaptive Immune Response

02:46

Microbiology with Diseases by Body System

Which of these HIV proteins binds to CD4 on human cells?
a. integrase
b. protease
c. gp 41
d. gp 120

Immune Disorders

Active and Passive Immunity

30 Practice Problems

00:30

Biochemistry

How is the gp120 protein important to HIV and its ability to confound the immune system?

Viruses, Cancer, and Immunology

07:54

Introduction to General, Organic and Biochemistry

(Chemical Connections $31 \mathrm{C}$ ) Describe the positive and negative effects of the innate immunity system on cancer cells.

Immunochemistry

01:00

Nester's Microbiology: A Human Perspective

Breast feeding provides which of the following to an infant?
a) Artificial active immunity
b) Artificial passive immunity
c) Natural active immunity
d) Natural passive immunity

Applications of Immune Responses

Immune Rejection

20 Practice Problems

03:13

Microbiology with Diseases by Body System

An antiserum is ____.
a. an anti-antibody
b. an inactivated vaccine
c. formed of monoclonal antibodies
d. the liquid portion of blood used for immunization

Immunization and Immune Testing

01:01

Microbiology with Diseases by Body System

The major inflammatory mediator released by degranulating mast cells in type I hypersensitivity is _______.
a. immunoglobulin
b. complement
c. histamine
d. interleukin
e. prostaglandin

Immune Disorders

00:54

Microbiology with Diseases by Body System

MHC class II molecules bind to _____________ and trigger _______________.
a. endogenous antigens; cytotoxic T cells
b. exogenous antigens; cytotoxic T cells
c. antibodies; $B$ cells
d. endogenous antigens; helper T cells
e. exogenous antigens; helper T cells

Adaptive Immunity

Disruptions in Immune Reponses

29 Practice Problems

00:45

Molecular Cell Biology

Because of oxygen and nutrient requirements, cells in a tissue must reside within $100 \mathrm{pm}$ of a blood vessel. Based on this information, explain why many malignant tumors often possess gain-of-function mutations in one of the following genes: $\beta F G F, T G F-\alpha,$ and $V E G F$.

Cancer

00:51

Biology of Humans: Concepts, Applications, and Issues

Which of the following is not a function of the inflammatory response?
a. preventing the injurious agent from spreading to nearby tissue
b. replacing injured tissues with connective tissue
c. disposing of cellular debris and pathogens
d. setting the stage for repair processes

Body Defense Mechanisms

00:19

Biology of Humans: Concepts, Applications, and Issues

Indicate the correct statement:
a. An antibody is specific to one particular antigen.
b. Antibodies are held within the cell that produces them.
c. Antibodies are produced by macrophages.
d. Antibodies can be effective against viruses that are inside the host cell.

Body Defense Mechanisms

Cancer and Immunity

25 Practice Problems

00:26

Biochemistry

What part of the immune system has been linked to progression of cancer?

Viruses, Cancer, and Immunology

04:00

Introduction to General, Organic and Biochemistry

A substance called laetrile is structurally related to carbohydrates. It has been suggested as a treatment for cancer, but it is not available in the United States. Its efficacy is doubtful, and it is inherently dangerous. Here is the structure. What is its relationship to carbohydrates? Do you think that the presence of the cyanide ( $-\mathrm{CN}$ ) group in the structure has a connection to the dangers associated with this compound? Explain.

Carbohydrates

02:16

Biology: Concepts and Investigations

As a treatment for bladder cancer, physicians may place a solution containing bovine tuberculosis bacteria into the patient's bladder. The bacteria bind to the bladder wall. Scientists do not fully understand why this treatment causes the patient's immune system to launch an attack against the cancer cells. Using your knowledge of how cytotoxic T cells are activated, write a prediction for how bovine tuberculosis bacteria might help a patient's immune system fight cancer.

The Immune System