©THEBRIGHT EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
Immunology: Introduction to the Immune
System Exam Study Guide.
2 Types of Immunity - Answers✔Innate and Adaptive
Antigen - Answers✔Any substance that is specifically recognized by lymphocytes or antibodies
First Line of Defense - Answers✔-Innate
-Anatomical: skin, mucuous membrane
-Mechanical: cilia in respiratory tract
-Physiological: lysozymes, low pH
Second Line of Defense - Answers✔-Innate
-Phagocytosis
-Immune surveillance
Third Line of Defense - Answers✔-Adaptive
-Mediated by B and T cells
Specificity - Answers✔Ensures that distinct antigens elicit specific responses
Diversity - Answers✔Enables immune system to respond to a large variety of antigens
Memory - Answers✔Leads to enhanced responses to repeated exposures to the same antigens
Clonal expansion - Answers✔Increases number of antigen-specific lymphocytes from a small
number of naive lymphocytes
Specialization - Answers✔Generates responses that are optimal for defense against different
types of microbes
Contraction and homeostasis - Answers✔Allows immune system to respond to newly
encountered antigens
Nonreactivity to self - Answers✔Prevents injury to the host during responses to foreign antigens
1
, ©THEBRIGHT EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
Clonal selection hypothesis - Answers✔Clones of lymphocytes specific for different antigens
develop before an encounter with these antigens, and each antigen elicits an immune response by
selecting and activating the lymphocytes for a specific clone
Humoral Immunity - Answers✔-Mediated by antibodies, which are produced by B lymphocytes
-part of adaptive immunity
-antibodies circulate through blood to neutralize and eliminate microbes extracellularly
-work to prevent infection inside cell
-B cells and antibodies can recognize different types of molecules
Cell-mediated Immunity - Answers✔-Adaptive
-mediated by T cells to defend against intracellular microbes
-Most T cells recognize only protein antigens
Active Immunity - Answers✔Induced in an individual by infection or vaccination
Passive Immunity - Answers✔Conferred on individual by transfer of antibodies or lymphocytes
from an actively immunized individual
Antigen Presenting Cells (APCs) - Answers✔-dendritic cells
-macrophages
-B cells
-follicular dendritic cells
Effector Cells - Answers✔Elimination of antigens. Main types include:
-T cells
-macrophages
-granulocytes
CD4+ T cells (helper T cells) - Answers✔Help B cells to produce antibodies and help phagocytes
destroy ingested microbe
CD8+ T cells (cytotoxic T lymphocytes, CTLs) - Answers✔Kill cells harboring intracellular
microbes
Regulatory T cells - Answers✔Subset of CD4+ cells that prevent or limit immune responses
B and T cells are born in the ________ - Answers✔Bone marrow
B cells mature in the _______ - Answers✔Bone marrow
2
ALL RIGHTS RESERVED.
Immunology: Introduction to the Immune
System Exam Study Guide.
2 Types of Immunity - Answers✔Innate and Adaptive
Antigen - Answers✔Any substance that is specifically recognized by lymphocytes or antibodies
First Line of Defense - Answers✔-Innate
-Anatomical: skin, mucuous membrane
-Mechanical: cilia in respiratory tract
-Physiological: lysozymes, low pH
Second Line of Defense - Answers✔-Innate
-Phagocytosis
-Immune surveillance
Third Line of Defense - Answers✔-Adaptive
-Mediated by B and T cells
Specificity - Answers✔Ensures that distinct antigens elicit specific responses
Diversity - Answers✔Enables immune system to respond to a large variety of antigens
Memory - Answers✔Leads to enhanced responses to repeated exposures to the same antigens
Clonal expansion - Answers✔Increases number of antigen-specific lymphocytes from a small
number of naive lymphocytes
Specialization - Answers✔Generates responses that are optimal for defense against different
types of microbes
Contraction and homeostasis - Answers✔Allows immune system to respond to newly
encountered antigens
Nonreactivity to self - Answers✔Prevents injury to the host during responses to foreign antigens
1
, ©THEBRIGHT EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
Clonal selection hypothesis - Answers✔Clones of lymphocytes specific for different antigens
develop before an encounter with these antigens, and each antigen elicits an immune response by
selecting and activating the lymphocytes for a specific clone
Humoral Immunity - Answers✔-Mediated by antibodies, which are produced by B lymphocytes
-part of adaptive immunity
-antibodies circulate through blood to neutralize and eliminate microbes extracellularly
-work to prevent infection inside cell
-B cells and antibodies can recognize different types of molecules
Cell-mediated Immunity - Answers✔-Adaptive
-mediated by T cells to defend against intracellular microbes
-Most T cells recognize only protein antigens
Active Immunity - Answers✔Induced in an individual by infection or vaccination
Passive Immunity - Answers✔Conferred on individual by transfer of antibodies or lymphocytes
from an actively immunized individual
Antigen Presenting Cells (APCs) - Answers✔-dendritic cells
-macrophages
-B cells
-follicular dendritic cells
Effector Cells - Answers✔Elimination of antigens. Main types include:
-T cells
-macrophages
-granulocytes
CD4+ T cells (helper T cells) - Answers✔Help B cells to produce antibodies and help phagocytes
destroy ingested microbe
CD8+ T cells (cytotoxic T lymphocytes, CTLs) - Answers✔Kill cells harboring intracellular
microbes
Regulatory T cells - Answers✔Subset of CD4+ cells that prevent or limit immune responses
B and T cells are born in the ________ - Answers✔Bone marrow
B cells mature in the _______ - Answers✔Bone marrow
2
