A&P II- Exam 3: Connect (Lymphatic and Immunity)

Interferon can cause the degradation of mRNA and prevention of the synthesis of viral proteins.

True

Plasma cells are B cells that produce antibodies.

True

When interferon from one cell attaches to a second cell, _________.

the recipient cell makes enzymes that degrade mRNA and prevent viral protein synthesis

Helper T cells secrete ________ to stimulate the proliferation of B cells.

Cytokines

Which type of immunity is mediated by B cells and the antibodies they secrete?

Humoral

Which of the following is produced by cytotoxic T cells?

Perforin, which makes holes in cell membrane of infected cells

Cytotoxic T cells produce cytotoxins which cause apoptosis of infected cells.

True

Indicate whether the label identifies an adaptive or innate immunity.

The structures and cells of the immune system can be characterized as participating in either adaptive or innate immunity. The structures that provide resistance to a broad grouping of pathogens without producing or requiring any memory are called innate.

Which of the following is true when interferon attaches to a cell?

The virus can enter the cell but can not replicate.

A small organ found along the course of a lymphatic vessel that filters the lymph and functions as an activation site for B and T cells is called a lymph __________.

node

Cytotoxic T cells recognize __________.

viral antigens and class-I MHC

Which cell phagocytizes an antigen and displays fragments of it on its surface?

Antigen-Presenting Cell (APC)

Drag each cell into the appropriate position to identify whether it is associated with antibody-mediated immunity, cell-mediated immunity, or both.

Cell-mediated immunity is useful in combating pathogenic elements inside of self-cells whereas antibody-mediated immunity works to defend against pathogens that exist and are created externally to one's cells. Cell-mediated responses utilize the activation of Cytotoxic T-cells, which are charged with destroying the infected cells. Antibody-mediated responses utilize B-lymphocytes to produce extraordinary quantities of antibodies, which work to render pathogens harmless via four mechanisms: neutralization, precipitation, agglutination, and complement fixation.

Which of the following statements accurately describes the difference between cellular and humoral immunity?

Cellular immunity directly attacks pathogens and infected cells while humoral immunity releases antibodies to do so.

Read each description regarding cellular and humoral immunity. Then, click and drag each into the appropriate category based on the form of immunity to which it applies.

Cellular immunity is a form of specific defense in which T lymphocytes directly attack and destroy diseased or foreign cells, and the immune system remembers the antigens of those invaders to prevent them from causing disease in the future. Humoral immunity is a more indirect method of defense than cellular immunity. Instead of directly attacking invaders, B lymphocytes produce antibodies that bind to antigens and tag them for destruction.

Helper T cells only interact with Class-I major histocompatibility complex (MHC) proteins.

False; When an antigen-presenting cell (APC) encounters and processes an antigen, it typically migrates to the nearest lymph node and displays it to the T cells. Cytotoxic and helper T cells patrol the lymph nodes and other tissues as if looking for trouble. When they encounter a cell displaying an antigen on an MHC protein (MHCP), they initiate an immune response. Helper T cells respond to both MHC I and MHC II proteins.

Interferon is produced by an animal cell that is infected by a bacterium.

False; When certain cells (especially leukocytes) are infected with viruses, they secrete proteins called interferons. These are of little benefit to the cell that secretes them but are like its "dying words" that alert neighboring cells and protect them from becoming infected. They bind to surface receptors on those cells and activate second-messenger systems within. This induces the synthesis of dozens of antiviral proteins that defend a cell by such means as breaking down viral genes or preventing viral replication. Interferons also activate NK cells and macrophages, which destroy infected cells before they can liberate a swarm of newly replicated viruses. Interferons also confer resistance to cancer since the activated NK cells destroy malignant cells.

Drag each label into the appropriate position to identify what type of immunity is classified by each label.

Immunity can be acquired through natural or artificial processes. Natural processes require either mother-to-offspring transference or through illness whereas artificial processes usually require modern medical interventions in the form of inoculation or injections. Passive immunity involves only antibodies that are received from an outside source whereas active immunity refers to the production and subsequent memory formation of immune response.

Which protein inhibits the viral infection of neighboring cells?

Interferon

Which of the following is true regarding interferon?

Interferon is produced by one cell and used to warn nearby cells of the same type.

Match each leukocyte listed with its correct defensive function.

Leukocytes play an important role in both nonspecific defenses and specific immunity. They are integral in both the second and third lines of defense. Each leukocyte has specific functions to aid the immune system.

Which body system maintains fluid balance, absorbs lipids, and protects the body against pathogens?

Lymphatic System

Drag each characteristic on the left into the appropriate position on the right to identify whether it is associated with T cells, B cells, or both.

Lymphocytes are vital in both forms of specific immunity. T cells are the most numerous and include the helper, regulator, and cytotoxic cell lines. B cells can differentiate into plasma cells responsible for the mass production of antibodies when stimulated. Both form memory cells and thus convey long-term immunity following a primary exposure.

Which of the following is true regarding infected cells?

They display peptide fragments of degraded viral proteins on their cell surface.

Which primary lymphoid organ is the site of B cell maturation?

Red Bone Marrow

Helper T cells interact with target cells by recognizing __________.

antigen-MHC protein complexes

Aggregations of lymphocytes in the connective tissues of mucous membranes are called __________.

lymphatic tissues