Ch 21 Immune System
The molecules that help to attract phagocytes to foreign cells are called
COMPLEMENT PROTIENS
Active immunity to tetanus, whooping cough, and polio can be artificially acquired when we ____________
receive vaccines
Which portion of the antibody's structure determines the antibody's class?
Constant Region
Inflammatory chemicals predominant producers are Helper T cells and Macrophages and activate many other immune cells
Cytokines
Kills virus-infected cells, cancerous cells, and is involved in graft rejection
Cytotoxic T Cell
The study of immunity and the immune system is called endocrinology T or F
FALSE - The study of immune system is Immunology
The final disposal of cell debris as inflammation subsides is performed by neutrophils T or F
False - Macrophages dispose of cell debris
What does fever accomplish?
Fever inhibits bacteria reproduction and speeds the repair process
Vasodilatation is part of the second line of defense because it results in greater flow of WBCs to the infected site. What chemical causes the vessels to dilate?
HISTAMINE
Which of the following types of immune responses involves the T cells stimulating the B cells to produce the antibodies?
HUMORAL IMMUNITY
Binds with a specific antigen presented by an antigen-presenting cell (APC)
Helper T Cell
Coordinate humoral and cellular immune responses
Helper T Cells =
Which cells stimulate both arms of the immune response?
Helper T Cells, Without helper T cells, there is no immune response.
Some viruses cripples the immune system by interfering with the activity of cells called
Helper T cells
When a virus infects cells, some cells have the ability to release ________ which are chemicals that activate other cells to defend themselves against the virus.
INTERFERONS
What is artificially acquired active immunity?
Induced by a vaccine, a substance that contains the antigen
Small proteins known as _____________ are secreted by virus-infected cells to help defend cells that have not yet been infected.
Interferons
Small proteins that bind with receptors on healthy cells to promote protein synthesis and prevent viruses from binding are called
Interferons
What inhibits viruses from entering and attacking healthy cells?
Interferons
Which type of molecule is produced by virus-infected cells to communicate to noninfected cells the presence of a virus?
Interferons, Interferons turn on genes for antiviral proteins
IgA
Is found in body secretions such as milk, saliva, and sweat
What cells will develop antigen receptors when they mature?
LYMPHOCYTES
IgE
Levels are greatly elevated during severe allergic responses
An example of an APC (antigen presenting cell) is a
MACROPHAGE
When a cell is invaded by a virus, the cell begins to produce foreign protein molecules. In order for the immune system to recognize that something is wrong, the abnormal proteins bind to a ________________________________________ and then display on the surface.
MAJOR HISTOCOMPATIBILITY COMPLEX I MOLECULE
Helper T cells "pick up" foreign antigens from macrophages and deliver these antigens to the B cells. The B cells become activated and begin to manufacture antibodies. Helper T cells get these foreign antigens from ____________________________________
MAJOR HISTOCOMPATIBILITY COMPLEX II PROTEIN
Macrophages will phagocytize a foreign cell. It then incorporates the foreign cell's antigen with the __________________________________ This is the macrophages way of presenting the foreign antigen to other immune cells.
MAJOR HISTOCOMPATIBILITY COMPLEX II PROTEIN.
Which cells are responsible for producing immunity against a disease after the first exposure of the same disease?
MEMORY B CELLS
When a person becomes infected with a pathogen that has a foreign antigen, the T cells and B cells respond. The various lymphocytes will kill the invader and then the patient is said to immune to that pathogen. They are immune to it because the second time they encounter the same pathogen, their ____________
MEMORY B CELLS will respond quickly.
A common APC
Macrophages
The final disposal of cell debris in acute inflammation is done by
Macrophages
Invoke inflammation when IgE cross-links to them
Mast Cells
May exist in the body for years and enable a quick response to subsequent meetings with the same antigen
Memory cell
IgG
Most abundant antibody found in the plasma
A cell with an abnormal or altered major histocompatibility complex is considered to be a __________
NONSELF cell.
The inflammatory response is part of the
NONSPECIFIC DEFENSE
The process by which antibodies bind to specific sites on bacterial exotoxins (toxic chemicals secreted by bacteria) to block their harmful effects is called?
Neutralization
What is the chief way the body responds to antigens?
Neutralization
Diapedesis happens when
Neutrophils squeeze through walls of capillaries into the tissues
Where are the major histocompatibility complex molecules located in reference to the cells?
ON THE OUTER LAYER OF THE CELL MEMBRANE
What is naturally acquired passive immunity?
Occurs during pregnancy, in which certain antibodies are passed from the maternal blood into the fetal blood in the form of IgG or in breast milk after birth.
The process of transferring antibodies from mom to baby is known as
PASSIVE IMMUNITY
Vaccines work to prevent a person from getting a specific virus during the flu season because the vaccine stimulates the
PRODUCTION OF MEMORY B CELLS
Immunity gained from injections of clonal antibodies to fight off a current pathogen invasion
Passive Artificial
Immunity gained from transport of antibodies across the placental membrane or through the mother's milk
Passive Natural
Chemical released by natural killer cells to cause cell lysis
Perforins
Neutrophils are
Phagocytes that will migrate to the site of an infection within a few hours
Cell that produces huge numbers of the same antibody (immunoglobulin)
Plasma Cell
Produce immunoglobulins
Plasma Cells
How do plasma cells assist with humoral immunity?
Plasma cells secrete highly-specific antibodies
Large antigen-antibody complexes can become insoluble and settle out of solution, a reaction called __________
Precipitation
Chemical secreted by white blood cells and macrophages to raise the body's temperature
Pyrogen
Slows or stops B and T cell activity once infection has been conquered
Regulatory T Cell
The body's first line of defense against the invasion of disease-causing microorganisms is
Skin and mucous membranes
Antigen presentation is essential for the activation and clonal selection of
T cells
A secondary response, triggered by memory cells, occurs much more rapidly than a primary response T or F
TRUE
Active artificially acquired immunity is a result of a vaccination. Usually, dead or attenuated pathogens are used T or F
TRUE
An antigen is a nonself substance that can mobilize the adaptive defenses and provoke an immune response T or F
TRUE
Antibodies bind to foreign antigens, which attract macrophages. True or False
TRUE
Complement Proteins usually works with antibodies in the "classical pathway" to open pores in the target cell membrane T or F
TRUE
Cytotoxic T cells cause cell lysis through the insertion of perforins into the target's membrane T or F
TRUE
Humoral Immunity involves antigens binding directly to the B cells causing the production of antibodies True or False
TRUE
IgE antibodies are involved in causing basophils to release histamine True or False
TRUE
Injured cells release chemicals such as histamine and kinins that dilate vessels, attract phagocytes and activate pain receptors T or F
TRUE
Leukotrienes cause dilation of the small blood vessels in an injured area T or F
TRUE
MAJOR HISTOCOMPATIBILITY COMPLEX (MHC) is involved with specific defenses T OR F
TRUE
SKIN would be considered a nonspecific barrier T or F
TRUE
T cells get their name from the fact that they develop in the thymus T or F
TRUE
The constant (C) regions of antibodies: 1) The constant regions are the same or nearly the same on all antibodies. 2) The constant regions form the "stem" of an antibody. 3) The constant regions determine the specific type of antibody class formed. 4) The constant regions determine how an antibody class will carry out its immune role. T or F
TRUE
The innate (nonspecific) defense system and adaptive (specific) defense system make up the immune system T or F
TRUE
The nonspecific defense by which complement proteins attach to sugars or proteins on the surface of foreign cells is called complement fixation. T or F
TRUE
NK cells lyse and kill cancer cells and virus-infected body cells before the adaptive immune system is activated T or F
TRUE - NK cells are unique as they have the ability to recognize stressed cells in the absence of antibodies and MHC, allowing for a much faster immune reaction
Without T lymphocytes there is no adaptive immune response T or F
TRUE - T cells, B cells, and other antigen presenting cells are all major cell types in adaptive immune response
Pyrogens target the hypothalamus and raise the body's temperature above normal T or F
TRUE - These chemicals are carried by the blood to the brain, where they disturb the functioning of the hypothalamus, the part of the brain that regulates body temperature.
Toll-like receptors are found on macrophages T or F
TRUE - Toll-like receptors are a group of single membrane spanning proteins found on the surfaceof sentinel cells such as macrophage and dendritic cells and play a key role in the innate immune response.
Antibiotics are chemicals that are harmful to bacteria. True or False
TRUE - you cannot kill a virus with antibiotics, they work on bacteria
Memory cells can circulate for years and respond quickly after any subsequent encounter with the same antigen. T or F
TRUE in Adaptive Immunity - Immunological Memory is used can lead to faster response to recurrent or subsequent infections
Exudate seeps from
the capillaries and contains clotting factors and antibodies
The activity of antigens and antibodies are involved in
Third line of defense - specific resistance
The defense system that recognizes precise foreign antigens is the body's
Third line of defense - specific resistance
The production of antibodies is the body's
Third line of defense - specific resistance
Interferons are substances released by some cells to fight
VIRUSES
The region of the antibody that varies from antibody to antibody is called the ___________________
Variable or V Region
Chemotaxis is described as the movement of cells along
a chemical gradient
Redness, heat, swelling, and pain are the four most common indicators of
acute inflammation
The third line of defense involves the
adaptive response mediated by lymphocytes
Each chain forming an antibody has a variable (V) region at one end and a much larger constant (C) region at the other end. Antibodies responding to different antigens have very different V regions, but their C regions are the same (or nearly so) in all antibodies of a given class. In each arm of the monomer, the V regions of the heavy and light chains combine to form an antigen-binding site shaped to "fit" a specific antigenic determinant. Consequently, each ____________________________________________________
antibody monomer has two antigen-binding regions.
The major role of ______________________ is to engulf antigens and present pieces of them to the cells that will deal with those fragments.
antigen-presenting cells
helper T cells bind to
antigen-presenting cells to begin the process of co-stimulation
Chemotaxis is the process
by which white blood cells are attracted to the site of an injury
Leukocytosis is
chemicals released from injured tissues stimulate rapid proliferation and release of cells
Membrane attack complexes (MAC) form holes in attacked cells causing them to burst; this is a result of
complement fixation
The binding of complement proteins to certain sugar or proteins on a foreign cell's surface is called
complement fixation
The process that begins when a helper T cell binds to a class II MHC protein on a displaying cell is known as
costimulation
Killer T cells, which kill virus-invaded body cells, are also called ___________
cytotoxic T cells.
Allergic contact dermatitis following skin contact with poison ivy would normally lead to
delayed hypersensitivity
The process by which neutrophils are squeezed through the capillary walls during the inflammatory process is called
diapedesis
Edema is caused by
excess blood flow to the injured area; helps to dilute harmful substances and brings in excess oxygen
Troublesome small molecules or incomplete antigens that may mount an attack that is harmful rather than protective are called
haptens
What type of T cell releases cytokines to indirectly rid the body of antigens?
helper T cells
Hyperemia is the
increased blood flow due to vasodilation of blood vessels entering the injured area
Chemotaxis is
inflammatory chemicals that attract neutrophils to the injured areas
IgM
large antibody released by plasma cells in a primary response
Tissue grafts harvested from a different animal species are known as ______________
xenografts
Cytotoxic T cells attack and
lyse cells that are not "self"
five major immunoglobulin/Antibody classes are
1) IgA, 2) IgD, 3) IgG, 4) IgE, 5) IgM
5 autoimmune disease
1) Multiple sclerosis = disease that destroys the myelin sheaths of the brain and spinal cord 2) Graves' disease = thyroid gland becomes hyperactive 3) type I diabetes mellitus = condition in which the pancreas produces little or no insulin 4) rheumatoid arthritis = disease that destroys the linings of joints 5) myasthenia gravis = disease that impairs communication between nerves and skeletal muscles
The inflammatory response is a normal response to tissue damage or the presence of foreign invaders. What is the correct sequence of events leading up to inflammation?
1) cells release histamine 2) vasodilation and permeability occurs 3) phagocytes arrive at the site and begin to engulf the foreign invader
The inflammatory process begins with releases of chemicals, which
1) dilate blood vessels, 2) attract phagocytes to the area, 3) cause capillaries to become leaky and 4) activate pain receptors
4 common vaccines are used for
1) pneumonia, 2) tetanus, 3) measles, 4) polio
What triggers the immune response?
1) pollen grains, 2) bacteria, 3) fungi, 4) virus particles
The four most common indicators of inflammatory response are?
1) redness, 2) heat, 3) swelling, 4) pain
There are molecules on the surface of cells that provide identity for the cells. The body either recognizes these cells as "self" or "nonself." Which of the follow are molecules that are NOT involved in cell identity?
1. Antigens 2' ANTIBODIES 3. major histocompatibility complex
Like all other blood cells, lymphocytes originate in red bone marrow from hematopoietic stem cells. During development, lymphocytes are "educated." The aim of this education is
1. Immunocompetence. Each lymphocyte must become able (competent) to recognize its one specific antigen by binding to it. This ability is called immunocompetence. 2. Self-tolerance. Each lymphocyte must be relatively unresponsive to self-antigens so that it does not attack the body's own cells. This is called self-tolerance.
An antigen is any substance capable of
mobilizing our immune system and provoking an immune response.
Memory B Cells is capable of
mounting a rapid attack against the same antigen in secondary immune responses
Immunity gained through injections of dead or attenuated strains of the disease-causing agents
Active Artificial
Immunity gained from being exposed to the pathogen and developing the illness
Active Natural
Margination happens when
neutrophils attach to Cell adhesion molecules (CAM) on the endothelial linings in the injured area
What is artificially acquired passive immunity?
An immediate, but short-term immunization provided by the injection of antibodies, such as gamma globulin, that are not produced by the recipient's cells.
List and describe the cells and chemicals the body uses as its second line of defense.
Answer: 1. Phagocytes, such as neutrophils or macrophages, engulf foreign particles. These cells are in nearly every body organ and confront pathogens that make it through the surface membrane barriers. 2. Natural killer cells, found in blood and lymph, are lymphocytes. They can lyse and kill cancer cells and virus-infected body cells. 3. The inflammatory response is a nonspecific response that occurs when body tissues are injured.
How do Antigen-presenting cells (APCs) work?
Answer: Antigen-presenting cells (APCs) engulf an antigen and present part of it on the membrane in combination with one of the APCs' own glycoproteins. T cells require the presentation of the antigen for activation and clonal selection. Without the presentation of antigens by APCs, the immune process would be severely impaired. T cell clone classes provide for cell-mediated immunity and include helper T cells, cytotoxic T cells, regulatory T cells, and memory cells.
The adaptive (specific) defense system issues an attack specific to
particular foreign substances
Antibodies provided by serum from an immune donor or an animal donor that do not challenge the B cells and thus provide ___________
passive immunity
Harmful or disease-causing microorganisms from which nonspecific defenses protect the body are called _______________
pathogens
What is naturally acquired active immunity?
person is exposed to a live pathogen, develops the disease, and becomes immune as a result of the primary immune response
Macrophages are
phagocytes derived from circulating monocytes
Why is the adaptive immune system described as a specific body defense?
Answer: The adaptive immune system is the specific line of defense which defends us from specific invaders. This system consists of humoral immunity B cells and Cellular immunity T Cells. This system differs from the innate system since it must be exposed to the invader before it can form a response.
Identify the four most common indicators and major symptoms of an acute inflammatory response and explain their origins.
Answer: The four most common indicators of the inflammatory response are redness, heat, swelling, and pain. Redness and heat are a result of dilation of blood vessels that increase blood flow to the injured area. Swelling occurs when increased permeability of the capillaries allows plasma to leak from the bloodstream into the tissue spaces. The excess fluid, or edema, triggers the activation of pain receptors in the area, accounting for the pain associated with an injury.
Why is the innate immune system described as a nonspecific body defense?
Answer: The innate immune system is the system we have when we're born. This system includes the skin and mucous membranes, called 1st line. The inflammatory response and proteins already present in our cells. They are internal defenses and considered 2nd line. This system is the first one to come into contact with a pathogen and thus is always prepared to defend the body. Therefore, we think of the innate system as the nonspecific body defense.
Contrast the primary humoral response with the secondary humoral response.
Answer: The primary humoral response occurs during the first encounter with an antigen. An antigen binds to a specific receptor on a specific B cell. The activated B cells proliferate to form a clone. While most of the B cell clone members become plasma cells that will secrete antibody molecules, B cells that do not become plasma cells will become memory cells. Memory cells exist for years and are capable of responding to the same antigen at a later meeting (immunological memory). Secondary humoral responses are the later immune responses that are faster, more prolonged, and more effective than the primary humoral response because preparations for this attack have already been made.
Humoral immunity is provided by?
Antibodies
Plasma Cells secret what?
Antibodies
Protein secreted by activated B cells in response to an antigen
Antibody
Any substance capable of provoking an immune response is called an
Antigen
Engulfs and presents parts of antigens on the membrane for recognition by T cells bearing receptors for the same antigen
Antigen-presenting cell (APC)
Lymphocytes are the main cells involved in our immune system. There are many types of lymphocytes, each with a specific function. Which ones are involved in producing antibodies?
B CELLS
The displaying of antigens on the surface of helper T cells or APCs will ultimately activate
B CELLS.
Progeny (clone members) of this cell form plasma cells and memory cells
B Cell