Porth Chapter 13

Question 1

Immune Response

Answer 1

The collective, coordinated response of the cells and molecules of the immune system

Question 2

Innate or nonspecific immunity

Answer 2

the natural resistance with which a person is born ​

Question 3

Adaptive or specific immunity

Answer 3

the second line of defense, responding less rapidly than innate immunity but more effectively​

Question 4

Lymphocytes

Answer 4

Cells that specifically recognize and respond to foreign antigens​

Question 5

Accessory cells

Answer 5

Macrophages and dendritic cells​

Function as antigen-presenting cells by the processing of a complex antigen into epitopes required for the activation of lymphocytes

Question 6

Cytokines

Answer 6

soluble proteins secreted by cells of both the innate and adaptive immunity

Question 7

Chemokines

Answer 7

cytokines that stimulate the migration and activation of immune and inflammatory cells​

Question 8

Colony-stimulating factors

Answer 8

stimulate the growth and differentiation of bone marrow progenitors of immune cells​

Question 9

Innate Immunity

Answer 9

Components ​

Epithelial barriers​

Phagocytic cells ​

Neutrophils and macrophages​

NK cells​

Plasma proteins​

Opsonins, cytokines, and acute-phase proteins ​

Induction of inflammatory response

Question 10

Soluble Mediators of Innate Immunity

Answer 10

Opsonins—facilitation of phagocytosis​

Acute-phase reactants, lectins, complement proteins​

IgG and IgM with adaptive immunity​

Cytokines—TNF, interleukins, interferons, and chemokines​

Acute-phase proteins​

Mannose-binding ligand and C-reactive protein​

Complement system​

Cytolysis, opsonization, chemotaxis, anaphylaxis

Question 11

Innate Recognition Systems

Answer 11

Pattern recognition receptors (PRRs)​

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Pathogen-associated molecular patterns (PAMPs) ​

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Toll-like receptors (TLRs)

Question 12

The Complement System

Answer 12

The complement system is found in the blood and is essential for the activity of antibodies. ​

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Activation of the complement system increases bacterial aggregation, which renders them more susceptible to phagocytosis.

Question 13

Adaptive Immunity

Answer 13

Able to recognize and react to a large number of microbes and nonmicrobial substances ​

Ability to distinguish among different, even closely related, microbes and molecules and to “remember” the pathogen by quickly producing a heightened immune response on subsequent encounters ​

Lymphocytes and their products ​

Antigen identification

Question 14

Humoral Immunity​

Answer 14

Mediated by molecules in the blood​

The principal defense against extracellular microbes and toxins

Question 15

Cell-Mediated Immunity or Cellular Immunity​

Answer 15

Mediated by specific T lymphocytes ​

Defends against intracellular microbes such as viruses​

Question 16

Regulatory Cells

Answer 16

Assist in orchestrating and controlling the immune response

Question 17

Effector Cells

Answer 17

Accomplish the final stages of the immune response with the elimination of the antigen ​

Activated T lymphocytes, mononuclear phagocytes, and other leukocytes function as effector cells in different immune responses.

Question 18

Antigens

Answer 18

substances foreign to the host that can stimulate an immune response. ​

Question 19

Antibodies

Answer 19

recognize antigens​

Receptors on immune cells ​

Secreted proteins​

Question 20

Types of Antigens

Answer 20

Bacteria​

Fungi​

Viruses​

Protozoa​

Parasites​

Nonmicrobial agents

Question 21

Properties of MHC Molecules

Answer 21

HLA Antigens​

Class I: HLA-A, HLA-B, HLA-C​

Class II: HLA-DR, HLA-DP, HLA-DQ​

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Distribution​

Class I: virtually all nucleated cells​

Class II: restricted to immune cells, antigen-presenting cells, B cells, and macrophages
Functions​

Class I: present processed antigen to cytotoxic CD8+ T cells; restrict cytolysis to virus-infected cells, tumor cells, transplanted cells​

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Class II: present processed antigenic fragments to CD4+ T Cells; necessary for effective interaction among immune cells​

Question 22

Antigen Presentation

Answer 22

Macrophages and dendritic cells process and present antigen peptides to CD4+ helper T cells. ​

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Capture antigens and then enable their recognition by T cells​

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Initiation of adaptive immunity

Question 23

B cells

Answer 23

Humoral immunity​

Memory

Question 24

T cells

Answer 24

Cell-mediated immunity​

Memory

Question 25

Identifying Factors of B Lymphocytes

Answer 25

Presence of membrane immunoglobulin that functions as the antigen receptor​ ​ Class II MHC proteins​ ​ Complement receptors​ ​ Specific CD molecules

Question 26

Functions of T Lymphocytes

Answer 26

The activation of other T cells and B cells​ ​ The control of intracellular viral infections​ ​ The rejection of foreign tissue grafts​ ​ Delayed hypersensitivity reactions

Question 27

IgG

Answer 27

displays antiviral, antitoxin, and antibacterial properties, responsible for protection of newborn; activates complement, and binds to macrophages​

Question 28

IgA

Answer 28

predominant Ig in body secretions; protects mucous membranes​ ​

Question 29

IgM

Answer 29

forms natural antibodies; prominent in early immune responses, activates complement​

Question 30

IgD

Answer 30

found on B lymphocytes, needed for maturation of B cells​ ​

Question 31

IgE

Answer 31

binds to mast cells and basophils; involved in parasitic infections, allergic and hypersensitivity reactions​ ​

Question 32

Central lymphoid organs (bone marrow and the thymus)​

Answer 32

Provide the environment for immune cell production and maturation

Question 33

Peripheral lymphoid organs 

Answer 33

Function to trap and process antigen and promote its interaction with mature immune cells

Question 34

Functional Groups of Cytokines

Answer 34

One group of cytokines (e.g., IL-1, IL-6, TNF) mediates inflammation by producing fever and the acute-phase response and by attracting and activating phagocytes (e.g., IL-8, IFN-γ).​ ​ Other cytokines are maturation factors for the hematopoiesis of white or red blood cells (e.g., IL-3, granulocyte–macrophage colony-stimulating factor [GM-CSF]).

Question 35

​​Active Immunity

Answer 35

Specific protection induced following exposure to antigens​

Question 36

Passive Immunity

Answer 36

Specific protection induced through transfer of protective antibodies against an antigen​ Transferred from another source ​ Maternal IgG crosses the placenta and protects the newborn during the first few months of life. ​ IgA in colostrum

Question 37

Development of an Immune Response

Answer 37

Fetal development at 5 to 6 weeks​ ​ Secondary lymphoid organs well developed at birth​ ​ IgA and IgM shortly after birth​ Reach adult levels by 1 year of age

Question 38

The Elderly Immune System

Answer 38

Declining ability to adapt to environmental stresses ​ Decline in immune responsiveness ​ Decrease in the size of the thymus gland ​ Biological clock in T cells ​ Altered responses of the immune cells to antigen stimulation