Adaptive Immunity Quiz

Overview of Adaptive Immunity and its Two Types: Humoral and Cell-Mediated Immunity

• Adaptive immunity has two types: humoral immunity and cell-mediated immunity.
• Humoral immunity is mediated by B lymphocytes and antibodies.
• Antibodies defend against extracellular microbes by preventing them from invading tissue cells and neutralizing toxins. They can also enhance the uptake of extracellular microbes into phagocytes.
• Intracellular microbes are defended against by cell-mediated immunity, which is mediated by T lymphocytes.
• Cell-mediated immunity is especially important to defend against intracellular organisms that can survive and replicate inside cells such as phagocytes.
• T lymphocytes activate phagocytes to destroy microbes that have been ingested and live within intracellular vesicles of these phagocytes.
• Other T lymphocytes kill any type of host cells that harbor infectious microbes in the cytoplasm or nucleus.
• The specificities of B and T lymphocytes differ in important respects. Most T cells recognize only peptide fragments of protein antigens presented on cell surfaces, whereas B cells and antibodies are able to recognize many different types of molecules.
• Immunity may be induced in an individual by infection or vaccination (active immunity) or conferred on an individual by transfer of antibodies or lymphocytes from an actively immunized individual (passive immunity).
• Passive immunity is useful for rapidly conferring immunity even before the individual is able to mount an active response, but it does not induce long-lived resistance to the infection.
• The only physiologic example of passive immunity is seen in newborns, who acquire antibodies during fetal life from their mothers through the placenta and in the neonatal period from breast milk.
• Passive immunity is useful for treating some immunodeficiency diseases with antibodies pooled from multiple donors and for emergency treatment of some viral infections and snakebites using serum from immunized donors.

Overview of Adaptive Immunity and its Two Types: Humoral and Cell-Mediated Immunity

• Adaptive immunity has two types: humoral immunity and cell-mediated immunity.
• Humoral immunity is mediated by B lymphocytes and antibodies.
• Antibodies defend against extracellular microbes by preventing them from invading tissue cells and neutralizing toxins. They can also enhance the uptake of extracellular microbes into phagocytes.
• Intracellular microbes are defended against by cell-mediated immunity, which is mediated by T lymphocytes.
• Cell-mediated immunity is especially important to defend against intracellular organisms that can survive and replicate inside cells such as phagocytes.
• T lymphocytes activate phagocytes to destroy microbes that have been ingested and live within intracellular vesicles of these phagocytes.
• Other T lymphocytes kill any type of host cells that harbor infectious microbes in the cytoplasm or nucleus.
• The specificities of B and T lymphocytes differ in important respects. Most T cells recognize only peptide fragments of protein antigens presented on cell surfaces, whereas B cells and antibodies are able to recognize many different types of molecules.
• Immunity may be induced in an individual by infection or vaccination (active immunity) or conferred on an individual by transfer of antibodies or lymphocytes from an actively immunized individual (passive immunity).
• Passive immunity is useful for rapidly conferring immunity even before the individual is able to mount an active response, but it does not induce long-lived resistance to the infection.
• The only physiologic example of passive immunity is seen in newborns, who acquire antibodies during fetal life from their mothers through the placenta and in the neonatal period from breast milk.
• Passive immunity is useful for treating some immunodeficiency diseases with antibodies pooled from multiple donors and for emergency treatment of some viral infections and snakebites using serum from immunized donors.

Overview of Adaptive Immunity and its Two Types: Humoral and Cell-Mediated Immunity

• Adaptive immunity has two types: humoral immunity and cell-mediated immunity.
• Humoral immunity is mediated by B lymphocytes and antibodies.
• Antibodies defend against extracellular microbes by preventing them from invading tissue cells and neutralizing toxins. They can also enhance the uptake of extracellular microbes into phagocytes.
• Intracellular microbes are defended against by cell-mediated immunity, which is mediated by T lymphocytes.
• Cell-mediated immunity is especially important to defend against intracellular organisms that can survive and replicate inside cells such as phagocytes.
• T lymphocytes activate phagocytes to destroy microbes that have been ingested and live within intracellular vesicles of these phagocytes.
• Other T lymphocytes kill any type of host cells that harbor infectious microbes in the cytoplasm or nucleus.
• The specificities of B and T lymphocytes differ in important respects. Most T cells recognize only peptide fragments of protein antigens presented on cell surfaces, whereas B cells and antibodies are able to recognize many different types of molecules.
• Immunity may be induced in an individual by infection or vaccination (active immunity) or conferred on an individual by transfer of antibodies or lymphocytes from an actively immunized individual (passive immunity).
• Passive immunity is useful for rapidly conferring immunity even before the individual is able to mount an active response, but it does not induce long-lived resistance to the infection.
• The only physiologic example of passive immunity is seen in newborns, who acquire antibodies during fetal life from their mothers through the placenta and in the neonatal period from breast milk.
• Passive immunity is useful for treating some immunodeficiency diseases with antibodies pooled from multiple donors and for emergency treatment of some viral infections and snakebites using serum from immunized donors.