Chapter 14 - An Introduction to Host Defenses
Skin is protected by the insoluble protein _____.
Keratin
_____ are participants of the specific immune response and are characterized as small, spherical cells with uniformly staining dark, round nuclei.
Lymphocytes
_____ react to foreign substances in the third line of defense.
Lymphocytes
The second most predominating type of leukocyte in circulation are _____.
Lymphocytes.
Organs lined with mucous membranes contain _____ to respond to the constant flux of microbes through these portals of entry.
MALT
A large, phagocytic white blood cell, derived from a monocyte, that leaves the circulation and plays a role in specific immune reactions while residing in tissues is called a(n) _____.
Macrophage
An example of genetic differences in susceptibility to disease is the sickle-cell trait that confers resistance to _____.
Malaria
What activates the lectin complement pathway?
Mannans
A non-motile cell bound to connective tissue along capillaries and contain granules that store (and release) mediators of inflammation and allergy such as histamine is known as a(n) _____ cell.
Mast
_____ are non-motile cells that are bound to connective tissue along capillaries that contain granules that store inflammatory mediators.
Mast cells
What is engulfed by phagocytes?
Microbes, dust, and dead cells
The third line of defense is a powerful system of specific responses to infectious agents called _____ or _____ immunity.
Acquired Adapted
The third line of defense is a powerful system of specific responses to infectious agents called _____ or ______ immunity.
Adaptive Acquired
Enzymatic digestion of bacteria inside of a phagolysosome can occur within 30 _____.
Minutes
When viewing leukocytes under a light microscope, staining with a hematologic stain cells produces some cells with granular structures in the cytoplasm. Leukocytes that do not have visible cytoplasmic granules under these conditions are called _____.
Agranulocytes
White blood cells with an unlobed, rounded nucleus and the absence of tiny inclusions in their cytoplasm are referred to as _____.
Agranulocytes
Acute inflammatory responses last from a few _____ to _____.
Minutes Hours
How lond do most acute inflammatory responses last?
Minutes to hours
Phagocytes have receptors that recognize pathogen-associated _____ _____ (PAMPS) on microbes.
Molecular patterns
A _____ is a large agranulocyte that differentiates into macrophages and dendritic cells.
Monocyte
What cell type makes up 3-7% of circulating leukocytes?
Monocytes
What are some agranulocytic white blood cells?
Monocytes Lymphocytes
Which white blood cells are agranulocytic?
Monocytes Lymphocytes
All organs and tissues contain a network of fibers and macrophages called the _____ system.
Mononuclear phagocyte
The __________ system is a network of fibers and macrophages that permeates the tissues of the body.
Mononuclear phagocyte
In _____ immunity, a type of adaptive immune response, specialized B cells secrete antibodies into the body fluids.
Humoral
What type of immunity mainly involved the action of B cells?
Humoral
What are some phagocytic digestion mechanisms?
Hydrolytic enzymes Cationic proteins Respiratory burst Nitric oxide
Human body temperature is normally maintained by the _____.
Hypothalamus
The _____ controls body temperature, hunger, thirst, fatigue, sleep, and circadian rhythms.
Hypothalamus
_____ is the study of all features of the body's response to, and defense against, infectious microbes, cancer, and allergy
Immunology
_____ is the study of all features of the body's sending and third line of defenses.
Immunology
Interferons are produced and secreted only by virally-_____ cells.
Infected
Trauma, infection, or an immune response can trigger a nonspecific immune response called _____.
Inflammation
_____ is a reaction to any traumatic event in the tissues that restores homeostasis.
Inflammation
The sec on cline of host defenses includes fever, _____, _____, _____, and _____.
Inflammation Phagocytosis Interferon Complement
In addition to responding to eukaryotic pathogens such as fungi and helminths, eosinophils also function in what?
Inflammatory reactions Allergic reactions
When a toll-like receptor binds to a foreign molecule, what is stimulated?
Inflammatory response Activity of lymphocytes
What is the correct order for the stages of complement activation?
Initiation Amplification Polymerization Membrane attack
_____ stimulates cells to produce antiviral proteins.
Interferon
_____ are small protein molecules produced by certain leukocytes and tissue cells in response to viral infection.
Interferons
Name some endogenous pyrogens.
Interleukin-1 TNF
_____ fluid is a plasma-like fluid that moves in and out of tissues, but does not contain red blood cells.
Interstitial
What is the purpose of vasodilation?
It increase blood flow to the injured area
True or False?: Complement action enhances inflammation.
True
True or False?: Interferon activates natural killer cells, T cells, B cells, and phagocytes.
True
True or False?: The membrane attack complex forms with all types of complement activation.
True
True or False?: Interferon is host-specific but not virus-specific.
True. Interferons can work against many types of viruses
The killing of microbes in the phagolysosome by products of oxygen metabolism is referred to as the _____-_____ system.
Oxygen-dependent
Phagocytes migrate to regions of inflammation in response to chemical messengers that have been released by phagocytes at the infection site that have detected specific microbial molecular patterns called _____.
PAMPS
Molecules shared by many microbes that act as "red flags" for white blood cells are known as _____.
PAMPs
The toll-like receptors found on phagocytes react with what structures of pathogenic microbes?
PAMPs
PRRs and TLRs interact with molecules on the surfaces of pathogens known as _____-_____ _____ _____.
Pathogen-associated molecular patterns
In addition to phagocytosis and initiation of inflammation, white blood cells have the capacity to discover foreign substances using surface receptors known as _____.
Pattern recognition receptors
Toll-like receptors are found within the cell membrane of _____.
Phagocytes
The main role of neutrophils is _____.
Phagocytosis
What is the main role of neutrophils?
Phagocytosis
What is the process in which foreign particles or cells are engulfed and then digested by specific immune cells?
Phagocytosis
The binding of PAMPs to TLRs results in stimulation of _____ and _____.
Phagocytosis Inflammation
The phagocyte initially encloses ingested materials in a vacuole called a(n) _____.
Phagosome
A(n) _____ cell is derived from an activated B lymphocyte and produces and secretes antibodies.
Plasma
What contains clotting factors, hormones, nutrients, dissolved gases, and wastes?
Plasma
_____ cells are derived from an activated B lymphocyte and produce and secrete antibodies.
Plasma
_____ is the fluid portion of the blood that carries proteins, nutrients, and clotting factors; and in which blood cells are normally suspended.
Plasma
_____ is the clear fluid from blood that contains clotting proteins, whereas _____ is the clear fluid from clotted blood that does not contain clotting proteins.
Plasma Serum
Formed elements in the blood that are involved in hemostasis and blood clotting are called _____.
Platelets
_____ are formed elements in the blood that are involved in hemostasis and blood clotting.
Platlets
Hematopoiesis occurs in which areas at some stage of life?
Red bone marrow Lymphatic organs Liver Yolk sac
What are the main functions of the inflammatory response?
Repair damaged tissues Destroy microbes and block their further invasion Mobilization and attraction of immune components to the site of infection or trauma
Ciliated epithelium and nasal hair are first-line defense adaptations that guard which body tract?
Respiratory
The _____ system, _____ fluid, _____, and lymphatic system are all body compartments that participate in immune function.
Reticuloendothelial Extracellular Blood
Lymphocytes are mainly involved in which host defense line?
Third line of defense
The function of the _____ gland is the maturation of T cells.
Thymus
What is the function of the phagolysosome?
To digest the ingested particles or cell
_____-_____ receptors are pattern recognition receptors found on macrophages and dendritic cells that recognize common molecules patterns on microbes and stimulate the inflammatory response.
Toll-like
The protein receptors found on macrophages and dendritic cells that recognize molecules on microbes and stimulate the inflammatory response are called _____.
Toll-like receptors
Chemotactic factors are cytokines that do what?
Attract WBCs to the site of inflammation
What are thrombocytes involved in?
Clotting Inflammation Hemostasis
What is contained in blood plasma?
Clotting factors Hormones Nutrients Wastes Dissolved gases
How does the resident biota act as the first line of defense?
Competing for nutrients Blocking access of pathogens Altering pH of environment
The _____ system enhances the ability of antibodies and phagocytic cells to clear pathogens from an organism.
Complement
The _____ system is a cascade of serum proteins that form a membrane attack complex.
Complement
A(n) _____ is a chemical substance produced by blood cells and tissue cells that regulated development, inflammation, and immunity.
Cytokine
Peptides produced by cells and tissues that damage cell membranes and lyse bacteria and fungi are _____.
Defensins
_____ are antimicrobial peptides produced by various tissues that damage cell membranes of bacteria and fungi.
Defensins
A line of phagocytic, antigen-presenting cells that are named for their long, thin cell processes are known as _____.
Dendritic cells
_____ is the shedding of the outermost layer of epithelial cells.
Dequamation
_____ is a peptide released by skin cells that breaks down bacterial membranes, and causes lysis of bacterial cells.
Dermicidin
The process of _____ refers to the transmigration of white blood cells out of capillaries into deeper tissues.
Diapedesis
The transmigration of white blood cells across capillary walls into deeper tissues is called _____.
Diapedesis
How does lymph fluid differ from blood?
Does not contain red blood cells
Accumulation of exudate that gives rise to local swelling and hardness is known as _____.
Edema
The complement system is a cascade of serum proteins that, when activated, results in what?
Enhancement of inflammation Enhancement of phagocytosis Formation of membrane attack complexes
Immunologic responses to fungal and helminth worm infections, allergy, and inflammatory reactions are carried out by _____.
Eosinophils
_____ are the granulocytes that are mostly involved in immunologic responses to fungal and helminth worm infections, allergy, and inflammatory reactions.
Eosinophils
"_____" is the scientific term for red blood cells.
Erythrocyte
Red blood cells are called _____.
Erythrocytes
_____ are the predominant type of cells circulating in the blood.
Erythrocytes
What are the products of infectious agents?
Exogenous pyrogens
Protein-rich fluid that builds up in the extracellular spaces during inflammation is called _____.
Exudate
During inflammation, a protein-rich fluid called _____ moves from the venues into the extracellular space, resulting in a swelling of tissue called _____.
Exudate Edema
True or False?: Interferons only bind to virally infected host cell receptors.
False
True or False?: Macrophages develop from activated neutrophils.
False
What are the functions of the spleen?
Filtration of pathogen from the blood Remove worn-out RBC from circulation
What are the roles of the lymph nodes?
Filtration of the lymphatic fluid Provision of immune cells
Coughing and sneezing are _____ line defenses that expel air from the respiratory tract.
First
What is correct order of events in phagocytosis?
1. Chemotaxis 2. Engulfment 3. Phagolysosome formation 4. Killing of bacterial cells 5. Release of cellular debris
List the predominance of circulating leukocytes from most to least.
1. Neutrophils 2. Lymphocytes 3. Monocytes 4. Eosinophils 5. Basophils
There are _____ major types of interferon.
3
There are how many different types of complement activation pathways?
3
Surface antigens activate the ______ complement pathway.
Alternative
What occurs as monocytes are transformed into macrophages?
An increase in size Enhancement of lysosomes
Plasma contains globulin proteins, which include _____.
Antibodies
What activates the alternative complement pathway?
Antigens
As part of the nonspecific chemical defense, semen contains a(n) _____ _____ that inhibits bacteria.
Antimicrobial chemical
What cell types can be activated/stimulated by interferon?
B cells Neutrophils Macrophages
Eosinophils target _____, _____, and _____.
Bacteria Helminths Fungi
What is considered to be "nonself"?
Bacteria Viruses Fungi
Along with mast cells, _____ are types of granulocytic leukocytes that mediate immediate allergies by releasing histamine.
Basophil
Which cell type has a pale-staining, constricted nucleus and contains granules with potent chemical mediators such as histamine?
Basophil
_____ are motile granulocytes that function in inflammatory events and allergies by releasing histamine.
Basophils
The digestive juices and _____ of the intestines provide nonspecific chemical defense against most microbes.
Bile
What component of the intestinal contents can be destructive to microbes?
Bile
What are the body compartments that participate in the immune system?
Bloodstream Lymphatic system Extracellular fluid Reticuloendothelial system
The fever response is defined as an abnormally elevated _____ _____.
Body temperature
T-lymphocytes directly attacking foreign or abnormal cells is known as _____ immunity.
Cell-mediated
Inborn, nonspecific defenses include _____, _____, and _____ barriers.
Chemical Genetic Physical
Substances known as _____ are released by cells in an injured area that act on endothelial cells and smooth muscle cells.
Chemical mediators Cytokines
_____ factors (chemokines) are cytokines that stimulate the movement of whit blood cells.
Chemotactic
_____ factors (chemokines) are cytokines that stimulate the movement of white blood cells.
Chemotactic
Phagocyte migration to inflammation areas when attracted by stimulants from both parasite and host tissue is an example of _____.
Chemotaxis
The process of _____ refers to the migration of WBCs toward chemical stimuli from an injured area.
Chemotaxis
The process of ______ refers to the migration of WBCs toward chemical stimuli from an injured area.
Chemotaxis
_____ is the migration of WBCs to the site of infection or trauma in response to chemical messages.
Chemotaxis
_____ inflammation can last anywhere from a few days to years as opposed to acute inflammation that lasts for minutes to hours.
Chronic
_____ inflammation can lead to host tissue damage or destruction.
Chronic
In the respiratory tract, _____ on the epithelium convey trapped foreign particles entrapped in mucus towards the pharynx for removal.
Cilia
The _____ complement pathway is activated by antigen-antibody complexes.
Classical
Serous fluid exudate is _____ while pus is opaque due to the presence of cells.
Clear
What associated lymphoid tissue provides immune function against intestinal pathogens and is a significant source of some types of antibodies?
GALT
What type of interferon regulates macrophages and lymphocytes?
Gammma
All interferons bind to surface receptors on target cells and induce changes in _____ expression.
Gene
What are the two groups in which leukocytes are divided into?
Granulocytic Agranulocytic
_____ is the process by which all blood cells are formed in bone marrow.
Hematopoiesis
Specialized macrophages called _____ migrate to certain tissues and remain there for their life span.
Histiocytes
The membrane attack complex creates _____ in the membranes or viral envelopes of pathogen, resulting in their eventual lysis.
Holes
Mannans activate the _____ complement pathway.
Lectin
The primary infection-fighting blood cells are called _____.
Leukocytes
_____ are primary infection-fighting blood cells, also known as white blood cells.
Leukocytes
Pluripotent stem cells can differentiate into what cell types?
Leukocytes Erythrocytes Thrombocytes
Lymph is transported through a system of _____ vessels.
Lymphatic
The _____ system is a system of vessels and organs that serve as sites for the development of immune cells, immune surveillance, and immune reactions.
Lymphatic
The spleen, thymus, lymph nodes, and GALT are all components of the _____ system.
Lymphatic
Hematopoiesis occurs in what areas at some stage of life?
Lymphatic organs Yolk sac Red bone marrow Liver
The circulatory system consists of the organs and tissues of both the _____ and _____.
Lymphatic system Circulatory system proper
Which cells are elevated in viral infections?
Lymphocytes
Which leukocytes are composed of small spherical cells that are involved in the specific immune response?
Lymphocytes
Moist _____ membranes line the eye and the respiratory, digestive, and urinary tracts.
Mucous
The flow of what substances carry microbes away from the respiratory tract?
Mucus Saliva
What adaptation guards the respiratory tract from the largest particles?
Nasal hair
Structures that comprise some of the first line defenses in the respiratory tract are _____ _____ and _____ epithelium.
Nasal hair Ciliated
What cell types are involved in the third line of host defense?
Natural killer cells Lymphocytes
Most aggregations of lymph nodes are found in the _____, _____, and _____ areas.
Neck Groin Armpit
Where are the sites of the major lymph nodes?
Neck, Groin, Armpit
An elevated number of white blood cells, in particular the _____, are a sign of bacterial infection.
Neutrophils
What type of leukocyte spends most of its life in the tissues serving as a major phagocytic cell?
Neutrophils
Which cells are elevated in bacterial infections?
Neutrophils
Which cells are the first phagocytes to act in inflammation?
Neutrophils
Which white blood cells are the primary components of pus?
Neutrophils
_____ are also called polymorphonuclear leukocytes or PMNs.
Neutrophils
_____ make up 55-90% of circulating leukocytes.
Neutrophils
What cell types are activate/stimulated by interferon?
Neutrophils B cells Macrophages
Which leukocytes are a granulocytes?
Neutrophils Basophils Eosinophils
What cell types are the major phagocytic cells of the immune system?
Neutrophils Monocytes Macrophages
Neutrophils are also called _____ neutrophils or PMNs.
Polymorphonuclear
What are some characteristics of B lymphocytes?
Produce antibodies when activated Move freely between lymphoid organs and connective tissue Mature in the bone marrow
Interferons stimulate cells to do what?
Produce antiviral proteins
Once a phagocyte has made contact with foreign substances or damaged material, it extends _____ to engulf the particles into a pocket for internalization.
Pseudopods
_____ is opaque matter formed during inflammation that consists of serum exudate, tissue debris, leukocytes, and microorganisms.
Pus
Pus-forming bacteria are also called _____ organisms.
Pyogenic
_____ is the ability to cause pus.
Pyogenic
A _____ is a circulating chemical substance that resets the hypothalamus to a body higher temperature setting.
Pyrogen
_____ is the ability to cause fever.
Pyrogenic
Circulating substances that can trigger fever are called _____.
Pyrogens
The flow of fluids such as _____ and _____ carriers microbes away from the respiratory tract.
Saliva Mucus
_____ secretions can have an antimicrobial effect.
Sebaceous
The host inflammatory response is a component of the _____ line of defense.
Second
Natural markers of the body that are recognized by the immune system are called _____.
Self
Normal cells of the body, classified as "_____", do not normally trigger an immune response.
Self
It is critical for the immune system to differentiate between _____ and _____.
Self Nonself
The clear fluid that remains after clotting proteins are removed from blood is called _____.
Serum
_____ is the clear fluid from clotted blood often used in immune testing and therapy.
Serum
Lymph moves through lymphatic vessels only through contraction of _____ muscles around lymphatic ducts.
Skeletal
The _____ provides an impervious and waterproof barrier to microbes.
Skin
What host barrier offers protection against microorganisms due to the presence of sebum, which has a high fatty acid content and acidic pH?
Skin
What is the first line of defense?
Skin
_____ is/are an external, confluent protective barrier.
Skin
Some pathogens are capable of infecting only one _____ of host.
Species
The _____ is similar in function to a lymph node except it filters blood instead of lymph.
Spleen
The pluripotent, undifferentiated cells in the bone marrow that give rise to the formed elements are called _____ cells.
Stem
What are the benefits of fever?
Stimulation of host Immune system Stimulation of host hematopoiesis Increased host metabolism Increased levels of phagocytosis Inhibited growth of temperature sensitive microbes
Which body site contains hydrochloric acid that inhibits many microbes?
Stomach
The direct attack of foreign or abnormal cells by _____-lymphocytes is known as cell-mediated immunity.
T
_____-lymphocytes mature in the thymus gland whereas _____-lymphocytes mature in the bone marrow.
T B
Microbes and other unwanted materials are flushed from the surface of the eyes by the flow of _____.
Tears
Where is the hydrolytic enzyme lysozyme found?
Tears Salive Sebum
What is the main important role of the reticuloendothelial system in immune function?
The provision of a passageway within and between tissues
The flow of lymph in lymphatic vessels is _____.
Unidirectional
Where is the spleen located?
Upper left abdomen
Mucosal-associated lymphoid tissue (MALT) responds to microbes entering through which body systems?
Urinary Respiratory Gastrointestinal
The urogenital tract receives partial protection from microbes through the flushing action of _____ flow through the urethra.
Urine
The _____ of monocytes contains stored digestive enzymes.
Vacuoles
_____ is a term for the widening of blood vessels that increases blood flow to an injured area.
Vasodilation
_____ is the main fluid in plasma.
Water
The liquid connective tissue consisting of erythrocytes, leukocytes, and platelets suspended in plasma is called __________.
Whole blood
_____ _____ is a liquid connective tissue consisting of erythrocytes, leukocytes, and platelets suspended in plasma.
Whole blood