Exam 4 Flashcards
A collection of cells and biochemicals that travel in lymphatic vessels
Lymphatic system
The lymphatic system is closely associated with the _________ system
Cardiovascular
What are the three functions of the lymphatic system?
- Transports excess interstitial fluid
- Absorbs lipids from the digestive system
- Defends the body against diseases
The lymphatic system transports excess ___________ away from the interstitial spaces, and returns it to the bloodstream.
Interstitial fluid
The lymphatic system absorbs lipids from the digestive system, and transports them to the __________
Bloodstream
The lymphatic system absorbs lipids from the digestive system, and transports them to the bloodstream; accomplished by lymphatic capillaries called ________
Lacteals
The term “_________” refers to the fact that many cells of the lymphatic system provide both defense against disease and permanent immunity against future infections.
Immune system
Name the (9) lymphatic pathways
- Lymphatic capillaries in tissues at capillary beds >
- Lymphatic vessels >
- Lymph nodes >
- Larger lymphatic vessels >
- Lymphatic trunks >
- Lymphatic collecting ducts >
- Subclavian veins in thorax >
- Superior vena cava >
- Right atrium of heart
The lymphatic capillaries are microscopic, ________ tubes
Closed-ended
Lymphatic capillaries are found wherever there are _________
Capillaries
Lymphatic capillaries are _____- walled
Thin
The walls of lymphatic capillaries are formed from what type of tissue?
Simple squamous epithelium
Once interstitial fluid enters the lymphatic capillaries, the fluid is called what?
Lymph
The lymphatic capillaries merge into ______ vessels
Lymphatic
The walls of lymphatic vessels are similar to veins, but ______
Thinner
Which are thinner? The walls of lymphatic vessels or lymphatic veins?
Lymphatic vessels
What are the three layers of lymphatic vessels?
Inner layer (endothelial lining)
Middle layer (smooth muscle and elastic fibers)
Outer layer (connective tissue)
How many layers are lymphatic vessels composed of?
Three
What type of tissue is the inner layer of a lymphatic vessel made of?
Endothelial lining
What type of tissue is the middle layer of a lymphatic vessel made of?
Smooth muscle and elastic fibers
What type of tissue is the outer layer of a lymphatic vessel made of?
Connective tissue
Lymphatic vessels contain semilunar ______, which allow one-way flow
valves
Lymphatic vessels contain semilunar valves, which allow ______ flow
One-way
Larger lymphatic vessels lead to ________ and then to larger lymphatic trunks
Lymph nodes
Larger lymphatic vessels lead to lymph nodes and then to larger __________
Lymphatic trunks
What are the arrows pointing to in this photo?
Valve in the lymphatic vessel
What drains lymph from the lymphatic vessels?
Lymphatic trunks
Lymphatic trunks are named for the regions they serve: _____, _______, ________, _____________, ________, ________.
Lumbar, intestinal, intercostal, bronchomediastinal, subclavian, and jugular
Lymphatic trunks train into what?
Lymphatic collecting ducts
How many lymphatic collecting ducts are there for the entire lymphatic system?
Two
Which is smaller, the right lymphatic duct or the thoracic duct?
The right lymphatic duct
Where does the right lymphatic duct begin?
The RIGHT thorax
Where does the right lymphatic duct empty?
Right subclavian vein
The right lymphatic duct drains which portion of the body?
The upper left portion
Which is longer and wider, the right lymphatic duct or the thoracic duct?
The thoracic duct
Which lymphatic duct drains everything NOT drained by the other?
Thoracic duct (drains everything NOT drained by the right lymphatic duct; majority of the body)
Which lymphatic duct begins as a sac called cisterna chyli?
Thoracic duct
The thoracic duct begins as a sac called what?
Cisterna chyli
Which lymphatic duct drains into the left subclavian vein?
The thoracic duct
Where does the thoracic duct drain?
The left subclavian vein
Bronchomediastinal trunk
Intercostal trunk
Internal jugular vein
Intestinal trunk
Jugular trunk
Lumbar trunk
Lymphatic vessels
Right brachiocephalic vein
Right lymphatic duct
Subclavian trunk
Thoracic duct
Thoracic duct
Axillary lymph nodes
Cisterna chyli
Left internal jugular vein
Left subclavian vein
Lymph nodes
Lymphatic trunk
Lymphatic vessels
Lymphatics of mammary gland
Right internal jugular vein
Right lymphatic duct
Right lymphatic duct
Right subclavian vein
Thoracic duct
Thoracic duct
List the order of the lymphatic pathway, starting with the lymphatic capillary?
Lymphatic capillary
Afferent lymphatic vessel
Lymph node
Efferent lymphatic vessel
Lymphatic trunk
Collecting duct
Subclavian vein
______ is tissue fluid that has entered a lymphatic capillary
Lymph
Lymph is _______ that has entered a lymphatic capillary
Tissue fluid
During tissue fluid formation, capillary blood pressure filters water and small molecules from what?
Plasma
How is tissue fluid formed?
Capillary blood pressure filters water and small molecules from plasma
Tissue fluid has about the same ______ as blood plasma
Composition
Tissue fluid contains what?
Water, dissolved nutrients, gases, hormones
Tissue fluid does NOT contain what?
Large plasma proteins
Tissue fluid does not contain large plasma proteins, which remain in the blood plasma why?
In order to maintain osmotic pressure necessary to draw fluid back into blood capillaries.
Tissue fluid = _______ - __________
Blood plasma - plasma proteins
Filtration from the plasma normally exceeds _______, leading to the net formation of tissue fluid
Reabsorption
Filtration from plasma normally exceeds reabsorption, leading to the net formation of tissue fluid. This increases the tissue fluid hydrostatic pressure within interstitial spaces, forcing fluid into lymphatic capillaries and forming what?
Lymph
What typically leads to the net formation of tissue fluid?
Filtration from plasma exceeding reabsorption
During lymph formation, Filtration from plasma exceeding reabsorption increases the ________ within interstitial spaces
tissue fluid hydrostatic pressure
During the formation of lymph, when the tissue fluid hydrostatic pressure increases within interstitial spaces, it forces fluid into what, forming lymph?
Lymphatic capillaries
The process of lymph formation prevents accumulation of excess tissue fluid, or ______
Edema
When a woman has axillary lymph nodes removed during breast cancer surgery, lymphatic drainage is obstructed from the upper limb, resulting in _______
Edema
Lymph inside lymphatic vessels has _____ hydrostatic pressure, like venous blood
Low
_________ influences the movement of lymph through the lymphatic vessels
Muscle activity
What are the three types of muscle activity that influences the movement of lymph through the lymphatic vessels?
Contraction of skeletal muscles, respiratory process, smooth muscle in the larger lymphatic vessels
Contraction of _______ muscles compresses lymphatic vessels, moving lymph
Skeletal
_________ process creates low pressure in thorax, and high pressure in abdomen during respiration; sends lymph from abdomen to thorax.
Respiratory
________ in the larger lymphatic vessels contracts to aid in the flow of lymph
Smooth muscle
______ in lymphatic vessels prevent backflow
Valves
Lymphatic flow is highest during what?
Physical exercise
Roles of lymphatic capillaries: Absorption of ______ in the small intestine, and delivery to the bloodstream
Dietary fats
Roles of lymphatic capillaries: Return of ________ filtered by blood capillaries to the bloodstream
Small proteins
Roles of lymphatic capillaries: Collection of excess ________
Interstitial fluid
Roles of lymphatic capillaries: Delivery of _________ to the bloodstream
Excess fluid
Roles of lymphatic capillaries: Delivery of ________ to the lymph nodes
Foreign particles
Roles of lymphatic capillaries: Flap-like valves between cells of lymphatic capillaries allow easy entry of?
Tissue fluid
Arteriole
Blood capillary
Lymphatic capillary
Lymphatic vessel
Tissue cells
Venule
Connective tissue
Epithelial cell
Filaments anchored to connective tissue
Flow of lymph
Movement of tissue fluid
Lymphatic tissue contains several cell types, including _______ and ________
Lymphocytes; macrophages
What does MALT stand for?
Mucosa-associated lymphoid tissue
Unencapsulated lymphatic tissue of the digestive, respiratory, urinary, and reproductive tracts
MALT (mucosa-associated lymphoid tissue)
Compact masses of lymphatic tissue
Lymphatic nodules
Tonsils and appendix are composed of ________
Lymphatic nodules
Aggregates of lymphatic nodules found in ileum (distal part of small intestine)
Peyer’s patches
_____ organs consist of encapsulated lymphatic tissue
Lymphatic
What are the lymphatic organs?
Lymph nodes, thymus, and spleen
Lymph nodes are usually _____-shaped.
Bean
Lymph nodes are usually less than ____ cm long
2.5
Lymph nodes are located along ________
Lymphatic vessels
Lymph nodes filter pathogens from ______
Lymph
Lymph nodes contain _____ to attack viruses, bacteria, and parasitic cells
Lymphocytes
Lymph nodes contain ______ to engulf and destroy foreign substances, damaged cells, and cellular debris
Macrophages
Lymph nodes are found in groups or chains along the paths of the larger _______ throughout the body
Lymphatic vessels
What are the major locations of lymph nodes ?
Cervical region
Axillary region
Supratrochlear region
Inguinal region
Pelvic cavity
Abdominal cavity
thoracic cavity
Lymph nodes are NOT found in which system?
Central nervous system
Blood vessels
Lymph node
Lymphatic vessels
Muscle
Afferent lymphatic vessel
Artery
Capsule
Efferent lymphatic vessel
Germinal center (B cells)
Hilum
Lymph flow
Lymph flow
Lymphatic nodule
Lymphatic sinus
Subcapsule (macrophages, B cells)
Trabecula
Vein
What are the two primary functions of lymph nodes?
Filter potentially harmful particles from the lymph; and immune surveillance: monitor body fluids via macrophages and lymphocytes
Lymph nodes are responsible for filtering potentially harmful particles from the _____
Lymph
Lymph node are responsible for immune surveillance: monitoring body fluids via ________ and _________
Macrophages; lymphocytes
Along with ______, the lymph nodes are centers for lymphocyte production
Red bone marrow
Along with red bone marrow, the lymph nodes are centers for ________ production
Lymphocyte
________ attack various pathogens in lymph nodes
Lymphocytes
Lymphocytes attack various pathogens in _________
Lymph nodes
________ engulf and digest foreign substances, damaged cells, and debris.
Macrophages
Soft, bilobed gland of the immune system
Thymus
How many lobes does the thymus gland have?
Two (bilobed)
Where is the thymus located?
Mediastinum
The thymus is divided into _______
Lobules
The lobules of the thymus contain ________ derived from progenitor cells in red bone marrow.
Lymphocytes .
The _________ of the thymus contain lymphocytes derived from progenitor cells in red bone marrow.
Lobules
The lobules of the _______ contain lymphocytes derived from progenitor cells in red bone marrow.
Thymus
The lobules of the thymus contain lymphocytes derived from _______ cells in red bone marrow.
Progenitor
The lobules of the thymus contain lymphocytes derived from progenitor cells in _____________
Red bone marrow
Most cells in the thymus are inactive; called __________
Thymocytes
Inactive cells in the thymus
Thymocytes
In the thymus, some cells mature into functional __________ (T cells), which leave the thymus to provide immunity.
T lymphocytes
Hormones produced in thymus; stimulate T cell maturation
Thymosins
What hormones stimulate T cell maturation in the thymus?
Thymosins
What immune system gland is large in infancy and early childhood, shrinks at puberty, and is small in adults?
Thymus gland
In the elderly, lymphatic tissue of the thymus is replaced by what other tissues?
Adipose and other connective tissues
Largest lymphatic organ
Spleen
Where is the spleen located?
Upper left part of the abdominal cavity
Which lymphatic organ resembles a large lymph node?
Spleen
Which lymphatic organ contains venous sinuses filled with blood?
Spleen
The spleen contains venous sinuses filled with what?
Blood
What are the two tissue types of the spleen?
White pulp (lymphocytes) and red pulp (RBCs, lymphocytes, and macrophages)
White pulp contains:
Lymphocytes
Red pulp contains:
RBCs, lymphocytes, and macrophages
The ______ filters blood like lymph nodes filter lymph
Spleen
What organ breaks down worn-out red blood cells?
Spleen
In the spleen, _______ engulf and destroy foreign particles
Macrophages
_______ defend the body against infection in the spleen
Lymphocytes
Where are lymph nodes located?
In groups or chains along the paths of larger lymphatic vessels
What is the function of lymph nodes?
Filter foreign particles and debris from lymph;
house lymphocytes that destroy foreign
particles in lymph; house macrophages that
engulf and destroy foreign particles and cellular
debris carried in lymph
Where is the thymus located, specifically?
In the mediastinum posterior to
the upper portion of the body
of the sternum
What is the function of the thymus?
Houses lymphocytes; differentiates thymocytes
into T lymphocytes
Where is the spleen located?
In the upper left portion of the
abdominal cavity, inferior to the
diaphragm and posterior and
lateral to the stomach
What is the function of the spleen?
Houses macrophages that remove foreign
particles, damaged red blood cells, and cellular
debris from the blood; contains lymphocytes
Lymphatic system defends body against infection by ?
Pathogens
Examples of pathogens?
Disease-causing agents, such as bacteria, viruses, complex
microorganisms like protozoa, and spores of multicellular organisms
like fungi
The presence and multiplication of a ______ in the body, if
unchecked may cause an infection
Pathogen
The presence and multiplication of a pathogen in the body, if
unchecked may cause an _______
Infection
Ability of body to prevent pathogen entry or destroy any
pathogens that enter the body
Immunity
What are the two immune mechanisms?
Innate (nonspecific) defenses, and adaptive (specific) defenses
What are the general immune defenses of the body referred to as?
Innate (nonspecific) defenses
Which immune mechanism protects against many types of pathogens?
Innate (nonspecific) defenses
Which immune mechanism is more specific and precise, targeting specific antigens?
Adaptive (specific) defenses
Which immune mechanism is carried out by lymphocytes that recognize certain foreign molecules?
Adaptive (specific) defenses
True or false: Certain species are resistant to diseases that affect other species
True
Certain species of cells lack what for a particular pathogen?
Receptors, temperature, or chemical environment
Skin and mucous membranes form what type of barrier?
Mechanical
Mechanical barriers prevent the entrance of _______
Pathogens
What kind of barrier is considered the first line of defense?
Mechanical barriers
All nonspecific defenses are part of the ________ of defense
Second line
What are some examples of mechanical barriers?
- A epidermis sloughs off, removes superficial bacteria
- Ciliated epithelium in respiratory tract traps and sweeps away pathogens
- Hair traps pathogens
- Tears, saliva, and urine wash away microorganisms
What produces local redness, swelling, heat, and pain
Inflammation
What is redness due to?
Vasodilation
What results from increased capillary permeability and fluid entry into tissue spaces?
swelling
What causes swelling?
increased capillary permeability and fluid entry
into tissue spaces
_____ is derived from blood arriving from deep areas of body
Heat
____ is due to stimulation of pain receptors
Pain
A process that walls off infection site, and inhibits spread of infection
Inflammation
During inflammation, ______ gather in area, and destroy pathogens by _____
WBCs; phagocytosis
During inflammation, _______ (fluids) that contain fibrinogen and other clotting factors may
form fibrin network
Exudates
During inflammation, Exudates (fluids) that contain fibrinogen and other clotting factors may
form _____ network
Fibrin
During inflammation, Following control of infection, _______ engulf and destroy dead cells
Phagocytes
During inflammation, Following control of infection, phagocytes engulf and destroy ________
Dead cells
During inflammation, Cells that were lost are replaced by ?
Cell division
Blood vessels dilate. Capillary permeability
increases and fluid leaks into tissue
spaces. What is the result?
Tissues become red, swollen, warm, and
painful
White blood cells invade the region. What is the response?
Pus may form as white blood cells,
bacterial cells, and cellular debris
accumulate.
Tissue fluids containing clotting factors
seep into the area. What is the result?
A clot containing threads of fibrin may form
Fibroblasts arrive. What is the result?
A connective tissue sac may form around
the injured tissues
Phagocytes are active. What is the result?
Bacteria, dead cells, and other debris are
removed
At the end of inflammation, Cells divide. What is the result?
Newly formed cells replace injured ones
_____ in body fluids provide a chemical barrier to pathogens
Enzymes
What are some examples of enzymes as chemical barriers?
Pepsin in gastric juice and lysozyme in tears destroy
microorganisms.
______ block viral replication, act against growth of tumors,
stimulate phagocytosis
Interferons
________ are peptides produced by neutrophils and other
granulocytes
Defensins
What is the purpose of defensins as chemical barriers?
they cripple microbes, by making openings in cell membranes or walls.
_____ are proteins that protect against many bacteria, yeast, and
some viruses
Collectins
A group of proteins in plasma and other body fluids
that stimulates inflammation, attracts phagocytes, and enhances
phagocytosis
Complement
Small population of lymphocytes
Natural killer (NK) cells
_____ cells are very different from B-cells and T-cells that provide
adaptive defenses
Natural killer
______ cells defend against viruses and cancer cells by secreting
cytolytic substances called perforins that lyse cell
membrane
Naturla killer
How do natural killer cells defend against viruses and cancer?
by secreting cytolytic substances called perforins that lyse cell
membrane
What types of cells enhance inflammation?
Natural killer (NK) cells
Removes foreign particles from lymph
Phagocytosis
_____ in the blood vessels and the tissues of the
spleen, liver, or bone marrow remove particles from blood
Phagocytes
Most active phagocytic cells are _____ and
_____
Neutrophils; monocytes
Chemicals from damaged tissue attract these phagocytic
cells to the injury; this is called _____
Chemotaxis
Monocytes that leave the blood become ______,
which can be free or fixed in tissues
Macrophages
________________ (reticuloendothelium)
consists of monocytes and macrophages of the body
Mononuclear phagocytic system
Begins when a viral or bacterial infection stimulates
lymphocytes to proliferate, producing cells that secrete a
substance called interleukin-1 (IL-1) which raises
thermoregulatory set point
Fever
A fever Begins when a viral or bacterial infection stimulates
lymphocytes to proliferate, producing cells that secrete a
substance called interleukin-1 (IL-1) which _______________
Raises thermoregulatory set point
IL-1 is also called _____________ (fire maker from
within)
Endogenous pyrogen
Elevated body temperature indirectly inhibits _________; causes liver and spleen to take up iron, making it
unavailable for bacteria and fungi to use in their normal
metabolism
Microbial growth
Elevated body temperature indirectly inhibits microbial
growth; causes liver and spleen to take up _____, making it
unavailable for bacteria and fungi to use in their normal
metabolism
Iron
Elevated body temperature indirectly inhibits microbial
growth; causes liver and spleen to take up iron, making it
unavailable for bacteria and fungi to use in their normal
______
Metabolism
High body temperature also increases ________ activity
Phagocytic
A species is resistant to certain diseases to which other species are
susceptible
Species resistance
Unbroken skin and mucous membranes prevent the entrance of some
infectious agents. What type of barrier is this?
Mechanical barriers
A tissue response to injury that helps prevent the spread of infectious agents
into nearby tissues
Inflammation
Enzymes in various body fluids kill pathogens. What type of barrier is this?
Chemical barrier
pH extremes and high salt
concentration also harm pathogens. What type of barrier is this?
Chemical barrier
Interferons induce production of other
proteins that block reproduction of viruses, stimulate phagocytosis, and
enhance the activity of cells such that they resist infection and the growth of
tumors. What type of barrier is this?
Chemical barrier
Defensins damage bacterial cell walls and membranes. What type of barrier is this?
Chemical barrier
Collectins
bind to microbes. What type of barrier is this?
Chemical barrier
Complement stimulates inflammation, attracts phagocytes,
and enhances phagocytosis. What type of barrier is this?
Chemical barrier
Fluids wash away microorganisms before they can firmly
attach to tissues. What type of barrier is this?
Mechanical barrier
Distinct type of lymphocyte that secretes perforins that lyse virus-infected
cells and cancer cells
Natural killer cells
Neutrophils, monocytes, and macrophages engulf and destroy foreign
particles and cells
Phagocytosis
Elevated body temperature indirectly inhibits microbial growth and increases
phagocytic activity
Fever
_______ of defense is resistance to particular pathogens or to
their toxins or metabolic by-products
Third line
the ability to distinguish molecules that are part of the
body (“self”) from “non-self” is a characteristic of what type of defenses?
Adaptive defenses
Non-self molecules that can evoke an immune
response
Antigens
_______ responses are carried out by lymphocytes and
macrophages that can recognize specific antigens
Adaptive
Adaptive responses are carried out by _____ and
_____ that can recognize specific antigens
Lymphocytes; macrophages
Adaptive responses are carried out by lymphocytes and
macrophages that can recognize specific _____
Antigens
What are the two types of adaptive defenses?
Cellular immune response (performed by immune cells)
Humoral immune response (performed by antibodies)
Cellular immune response is performed by _______ cells
Immune
Humoral immune response is performed by _______
Antibodies
What is the first line of defense against pathogens?
Mechanical barriers (skin and mucous membranes)
What is the second line of defense, after a pathogen has entered the body?
Chemical barriers
Natural killer cells
Inflammation
Phagocytosis
Fever
What is the third line of defense against pathogens?
Cellular immune response
Humoral immune response
What enables the cells to
recognize non-self antigens?
Receptors on the surface of lymphocytes
Lymphatic system responds to ____________, but not self antigens
(under normal circumstances)
Non-self antigens
Antigens may be:
Progeins
Polysaccharides
Glycoproteins
Glycolipids
Most effective antigens are ______ and _______ molecules
Large; complex
Small molecules that are not antigenic by themselves, but
when they combine with a large molecule in the body, they can evoke an
immune response
Haptens
Lymphocytes are produced throughout life, starting during ____ development.
Fetal
________ are produced throughout life, starting during fetal development.
Lymphocytes
_______ releases unspecialized lymphocyte precursors into blood.
Red bone marrow
Red bone marrow releases ___________ into blood.
Unspecialized lymphocyte precursors
Red bone marrow releases unspecialized lymphocyte precursors into _____
Blood
Half of all unspecialized lymphocyte precursors settle in the _____, specialize, and are then released (become B cells)
Thymus
Half of all unspecialized lymphocyte precursors settle in the thymus, specialize, and are then released (become ______)
B cells
Other half of cells differentiate in red bone marrow, and are then released
(become _____)
B cells
Unspecialized lymphocyte precursors differentiate in…
Half in the thymus, half in red bone marrow
What are the two main types of lymphocytes
T lymphocytes
B lymphocytes
What does the T in T-cells stand for?
Thymus-derived; lymphocytes
What does the B in B-cells stand for?
B = bursa of fabricius (in chickens); derived from red bone marrow
Which lymphocytes specialize in the thymus?
T lymphocytes
Where do T-lymphocytes specialize?
The thymus
Which cells make up 70 to 80% of circulating lymphocytes after specialization?
T lymphocytes
Which cells make up 20 to 30% of lymphocytes in blood?
B lymphocytes
Which lymphocytes are abundant in lymph nodes, spleen, bone marrow, and intestinal lining?
B lymphocytes
What is the origin of undifferentiated T cells?
Red bone marrow
What is the origin of undifferentiated B cells?
Red bone marrow
Where is the site of differentiation for T cells?
Thymus
Where is the site of differentiation for B cells?
Red bone marrow
What are the primary locations for T cells?
Lymphatic tissues
70 to 80% of the circulating lymphocytes in blood
What are the primary locations for B cells?
Lymphatic tissues
20 to 30% of the circulating lymphocytes in blood
What are the primary functions of T cells?
Provide cellular immune
response in which T
cells interact directly
with the antigens or
antigen-bearing agents,
to destroy them
What are the primary functions of B cells?
Provide humoral immune
response in which B cells
interact indirectly, producing
antibodies that destroy the
antigens or antigen-bearing
agents
A lymphocyte has to be _____ before it can respond to presence of an antigen
Activated
__________ requires that antigenic fragments be attached to antigen-
presenting cell (APC, accessory cell)
T cell activation
T cell activation requires that antigenic fragments be attached to an ___________
Antigen-presenting cell (APC, accessory cell)
APC phagocytizes antigen, digests it, and displays antigenic fragments on its own cell membrane, bound to protein that is part of the _____________ or human leukocyte antigens (HLA)
Major histocompatibility complex (MHC)
When specific T cell encounters an APC displaying antigenic fragments bound to
MHC proteins, it can now recognize antigen as foreign
Foreign
When specific T cell encounters an APC displaying antigenic fragments bound to
MHC proteins, it can now recognize antigen as foreign. T cell is now ______
Activated
T cells can secrete polypeptides called _______, which enhance some cellular
responses to antigens
Cytokines
What are the types of specialized T cells?
Helper T cells
Cytotoxic T cells
Memory T cells
Specialized T cells called _________ Activate other cells; stimulates B cells to produce antibodies
Helper T cells
Specialized T cells called ___________ Attack virally infected or cancerous cells
Cytotoxic T cells
Specialized T cells called __________ provide future immune protection
Memory T cells
What are the four types of cytokines?
Colony-stimulating factors
Interferons
Interleukins
Tumor necrosis factor
Cytokines that Stimulate bone marrow to produce
lymphocytes
Colony-stimulating factors
Cytokines that Block viral replication, stimulate
macrophages to engulf viruses, stimulate
B cells to produce antibodies, attack
cancer cells
Interferons
Cytokines that Control lymphocyte differentiation and
proliferation
Interleukins
cytokine that Stops tumor growth, releases growth
factors, causes fever that accompanies
bacterial infection, stimulates lymphocyte
differentiation
Tumor necrosis factor
B cells can be _______ when an antigen fits the shape of their
receptors, and binds to them
Activated
Further B cell activation requires ________ from T cells
Cytokines
Once proper cytokines are released from Helper T cells, B cells
respond by _________, enlarging clone of identical cells
Proliferating
Some new B cells become ________, which provide
future immunity
Memory B cells
Other new B cells differentiate into _______, which produce
and secrete large globular proteins called antibodies or
immunoglobulins
Plasma cells
Other new B cells differentiate into plasma cells, which produce
and secrete large globular proteins called ______ or ________
Antibodies; immunoglobulins
Since antibodies are carried by the blood (a body fluid) to the
infection site, this type of response is called the humoral immune
response, or the ______________
Antibody-mediated immune response
Antibodies are _____ proteins
Globular
Antibodies Make up the __________ fraction of plasma proteins
Gama globulin
Antibodies are also called
Immunoglobulins
Antibodies are ___-shaped proteins, composed of 4 amino acid chains: 2 heavy
and 2 light chains
Y
Antibodies are y-shaped proteins, composed of 4 amino acid chains: 2 ____
and 2 ____ chains
Heavy; light
Each type of antibody has unique ________ sequence and
conformation, making it specific for its antigen
Amino acid
What are the 5 major types of antibodies or immunoglobulins?
IgG
IgA
IgM
IgD
IgE
Which type of antibody makes up 80% of antibodies; act on bacteria, viruses, toxins
IgG
Which type of antibody makes up 13% of antibodies; found in exocrine gland secretions
IgA
Which type of antibody makes up 6% of antibodies; act on antigens in foods and bacteria
IgM
Which type of antibody makes up <1% of antibodies; found on B cell surfaces, common in infants
IgD
Which type of antibody makes up <1% of antibodies; found in exocrine gland secretions
IgE
Where does IgG occur?
Plasma and tissue fluid
What are the major functions of IgG?
Defends against bacteria, viruses,
and toxins; activates complement
Which immunoglobulin occurs in plasma and tissue fluid?
IgG
Which immunoglobulin Defends against bacteria, viruses,
and toxins; activates complement
IgG
Where does IgA occur?
Exocrine gland secretions
What are the major functions of IgA?
Defends against bacteria and viruses
Which immunoglobulin comes from exocrine gland secretions?
IgA
Which immunoglobulin defends against bacteria and viruses?
IgA
Where does IgM occur?
Plasma
What are the major functions of IgM?
Reacts with antigens on some red
blood cell membranes following
mismatched blood transfusions;
activates complement
Which immunoglobulin occurs in plasma?
IgM
Which immunoglobulin Reacts with antigens on some red
blood cell membranes following
mismatched blood transfusions;
activates complement
IgM
Where does IgD occur?
Surface of most B lymphocytes
What are the major functions of IgD
Activates B cell
Where does IgE occur?
Exocrine gland secretions
What are the major functions of IgE?
Promotes inflammation and allergic responses
What are the three different ways antibodies respond to antigens?
Agglutination
Precipitation
Neutralization
Clumping of antigens, making phagocytosis easier
Agglutination
Make antigens insoluble, making phagocytosis easier
Precipitation
Cover toxic portions of antigens, making them harmless
Neutralization
More effective against antigens than direct attack
Activation of complement
Activation of ______Occurs with certain IgG and IgM antibodies
Complement
What are the four actions of activated complement proteins?
Opsonization
Chemotaxis
Lysis
Neutralization
When activated complement proteins Coat antigen-antibody complexes, it is called
Opsonization
When activated complement proteins attract macrophages and neutrophils, it is called
Chemotaxis
When activated complement proteins rupture cell membranes of pathogens, it is called
Lysis
When activated complement proteins change the structure of viruses so they are harmless, it is called what?
Neutralization
Inflammatory chemicals cause what?
Edema; vasodilation
stimulation of local change and inflammation occur to help prevent the spread of ?
Infection
A direct attack by antibodies produces what type of effect?
Agglutination
Precipitation
Neutralization
What is it called when antigens clump?
Agglutintaion
What is it called when antigens become insoluble?
Precipitation
What is it called when antigens lose toxic properties?
Neutralization
Activation of complement (antibodies combined with antigens) produces what type of effect?
Opsonization
Chemotaxis
Agglutination
Lysis
Neutralization
What is it called when antibodies alter antigen cell membranes so cells are more susceptible to phagocytosis?
Opsonization
What is it called when antibodies attract macrophages and neutrophils into the region?
Chemotaxis
What is it called when antibodies clump antigen-bearing cells?
Agglutination
What is it called when antibodies allow rapid movement of water and ions into the foreign cell, causing osmotic rupture of the foreign cell?
Lysis
What is it called when antibodies alter the molecular structure of viruses, making them harmless?
Neutralization
What are localized changes by antibodies?
Inflammation
A localized change called ________ helps prevent the spread of antigens
Inflammation
__________ makes use of immune system components
to fight disease (the humoral immune response by antibodies
and the cellular immune response by cytokines).
Immunotherapy
Immunotherapy makes use of ____________________
to fight disease (the humoral immune response by antibodies
and the cellular immune response by cytokines).
immune system components
A specific B cell, which produces a single type of antibody (__________),
can be fused with a cancerous cell to produce a cell that produces 1 type of
antibody, and keeps dividing
Monoclonal
Antibodies Used in research, agriculture, pregnancy tests, detecting new or
reoccurring cancers, delivering medications specifically to tumors
Monoclonal antibodies
Why are monoclonal antibodies used in research?
They can be fused with a cancerous cell to produce a cell that produces 1 type of antibody and keeps dividing
______ can now be produced in large quantities, due to recombinant DNA and
monoclonal antibody techniques
Cytokines
Cytokines can now be produced in large quantities, due to recombinant DNA and
____________________
Monoclonal antibody techniques
A type of antibody used to treat leukemia, multiple sclerosis, hepatitis, genital warts,
melanoma, kidney cancer
Cytokines
______ immune response: Produced by first encounter with antigen
Primary
During primary immune response, __ and __ cells specific for the antigen become activated
B; T
During ___________ immune response, B and T cells specific for the antigen become activated
Primary
During ______ immune response, Plasma cells releases IgM, and then IgG antibodies
Primary
During primary immune response, Plasma cells releases ____, and then ____ antibodies
IgM; IgG
During _____ immune response, First antibodies appear in 5 to 10 days, and remain for several weeks
Primary
During primary immune response, First antibodies appear in _____ days, and remain for several weeks
5 to 10
During primary immune response, _____ cells are also produced
Memory B
Response to subsequent exposure to same antigen corresponds to which immune response?
Secondary
Which immune response Produces high concentration of antibodies in 1 to 2 days
Secondary
Which immune response is Accomplished by Memory B cells and Memory T cells
Secondary
After which immune response to
Antibodies remain for months or years
Secondary
After which immune response do memory B cells live for many years
Secondary
What are the two classifications of immunity based on how it is acquired
Naturally or artificially
what type of immunity is Obtained by a natural process, such as getting and recovering from the disease, or given from mother to fetus or infant
Natural
What type of immunity is Obtained by an injection, instead of a natural process
Artificial
What are the two classifications of immunity based on whether it is temporary or permanent
Passive or active immunity
Temporary immunity obtained via antibodies; no antigen exposure; no immune response is evoked in person’s immune system
Passive immunity
Permanent immunity obtained via antigen contact; immune response is evoked, and memory B cells are produced
Active immunity
What is the difference between passive or active immunity?
Passive immunity is acquired from antibodies and not exposure to the antigen. i.e., a vaccine. Active immunity is acquired from exposure to the antigen itself.
What is the mechanism by which naturally acquired active immunity occurs?
Exposure to live pathogens
What is the method by which artificially acquired active immunity occurs?
Exposure to a vaccine containing weakened or dead pathogens or their components
Method by which naturally acquired passive immunity occurs?
Antibodies passed to fetus from pregnant woman with active immunity or to newborn
through colostrum or breast milk from a woman with active immunity
Method by which artificially acquired passive immunity occurs?
Injection of antiserum containing specific antibodies or antitoxin
What is the result of naturally acquired active immunity?
Stimulation of an immune
response with symptoms of a
disease
What is the result of artificially acquired active immunity?
Stimulation of an immune
response without symptoms of
a disease
What is the result of naturally acquired passive immunity?
Short-term immunity for
newborn without stimulating an
immune response
What is the result of artificially acquired passive immunity?
Short-term immunity without
stimulating an immune
response
Exaggerated immune response to non-harmful antigen
Hypersensitivity
With ______, the person is pre-sensitized to a certain antigen
hypersensitivity
Some ______ can affect almost anyone (exaggerated immune response
Hypersensitivities
Some ________ can affect only people with inherited ability to have an exaggerated immune response
hypersensitivities
What are the four types of sensitivities?
- Immediate reaction
- Antibody-dependent cytotoxic reaction
- Immune-complex reaction
- delayed-reaction hypersensitivity
Which type of sensitivity is an allergy?
Type I (immediate-reaction)
During type I (immediate-reaction) sensitivity, a person produces many IgE antibodies against a specific ________
Allergen
What type of hypersensitivity Occurs minutes after contact with allergen; histamine is released
Type 1 (immediate reaction)
What type of hypersensitivity has symptoms that include hives, hay fever, asthma, eczema, gastric disturbances,
and anaphylactic shock (a life-threatening severe form)
Type 1 (immediate reaction)
During which hypersensitivity reaction does the Antigen bind to specific cell; causes phagocytosis, and complement lyses antigen
Type II (antibody-dependent cytotoxic reaction)
Which type of hypersensitivity reaction is a transfusion reaction?
Type II (antibody-dependent cytotoxic reaction)
During which hypersensitivity reaction do Antigen-antibody complexes form and deposit in certain tissues
Type III (immune-complex) reaction
Which hypersensitivity reaction Damages tissue via phagocytosis and complement-binding
Type III (immune-complex reaction)
In which hypersensitivity reaction can Antibody complexes not be cleared from the body
Type III (immune-complex) reaction
What is an example of a type III hypersensitivity?
Rheumatoid arthritis
Which hypersensitivity reaction may affect anyone?
Type IV (delayed reaction)
Which hypersensitivity results from repeated exposure of skin to allergen
Type IV (delayed-reaction)
with which hypersensitivity reaction does the Allergen activate T cells in skin, which release chemicals that cause
eruptions and inflammation
Type IV (delayed-reaction)
Which type of hypersensitivity reaction takes about 48 hours to occur?
Type IV (delayed reaction)
What is the general response of a type I (immediate-reaction) hypersensitivity reaction?
Overproduction of IgE antibodies
What is the general response of a type II (antibody-dependent cytotoxic reaction) hypersensitivity reaction?
Phagocytosis and complement-mediated lysis of antigen
What is the general response of a type III (immune complex reaction) hypersensitivity reaction?
Phagocytosis and lysis cannot clear antigen-antibody complexes
What is the general response of a type IV (delayed-reaction) hypersensitivity reaction?
T cells and macrophages release chemical factors into the skin
What is an example of a type I (immediate) hypersensitivity reaction?
Hay fever
What is an example of type II (antibody-dependent cytotoxic reaction) hypersensitivity reaction?
Mismatched blood transfusion
What is an example of type III (immune complex reaction) hypersensitivity reaction?
Autoimmunity
What is an example of type IV (delayed-reaction) hypersensitivity reaction?
Dermatitis
What are the tissues and organs that can be transplanted?
Bone, cornea, kidney, liver, pancreas, heart, bone marrow, skin, lungs
When the donor’s tissues are recognized as foreign, there is a _________ reaction;
recipient’s immune system will try to destroy foreign tissue
tissue rejection
Damage to recipient’s tissues by molecules in immunologically
active transplanted tissue, such as bone marrow
Graft-versus-host disease
______ reaction resembles the cellular immune response against antigens
Rejection
Important to match ___ antigens between donor and recipient
MHC
the greater the ________
difference, the stronger and faster the rejection reaction will occur
antigenic
___________ drugs are used to prevent rejection
Immunosuppressive
Well-matched transplants may not require life-long immunosuppressive drugs, if ________________ from donor are given along with transplant
Bone marrow stem cells
What are the different types of grafts?
Autografts
Isografts
Allografts
Xenografts
What is an autograft?
A transplant from self
What is an isograft?
a transplant from an identical twin
Which types of grafts would not cause a rejection reaction?
Autografts and isografts
What is an allograft?
A transplant from a person other than an identical twin
What is a xenograft?
A transplant from a different species
Which types of grafts would tend to cause a rejection reaction?
Allografts and xenografts
Who would the donor be for an isograft?
Identical twin
Who would the donor be for an autograft?
Self
Who would the donor be for an allograft?
Same species
Who would be the donor for a xenograft?
Different species
What is an example of an isograft?
Bone marrow transplant from a
healthy twin to a twin who has
leukemia
What is an example of an autograft?
Skin graft from one part of the body to replace burned skin
What is an example of an allograft?
Kidney transplant from a relative or closely matched donor
What is an example of a xenograft?
Heart valves from a pig
An attack by the immune system against own tissues
Autoimmunity
The immune system fails to distinguish “self” from “non-
self,” and the body produces antibodies called
_________
Autoantibodies
In autoimmunity, _________ cells also attack the body’s tissues and organs
Cytotoxic T
Various autoimmune disorders affect different types of _____
Cells
True or false? There are several theories concerning the cause(s) of
autoimmune disorders, but no single cause has been
established
True
What are the different autoimmune disorders?
Glomerulonephritis
Graves’ disease
Type 1 diabetes mellitus
hemolytic anemia
Multiple Sclerosis
Myasthenia gravis
Pernicious anemia
Rheumatic fever
Rheumatoid arthritis
Systemic lupus erythematosus
Ulcerative colitis
Symptoms of glomerulonephritis
Lower back pain
Symptoms of graves’ disease
Restlessness, weight loss, irritability, increased heart rate and blood pressure
Symptoms of type 1 diabetes mellitus
Thirst, hunger, weakness, emaciation
Symptoms of hemolytic anemia
Fatigue and weakness
Symptoms of multiple sclerosis
Weakness, incoordination, speech disturbances, visual complaints
Symptoms of myasthenia gravis
muscle weakness
Symptoms of pernicious anemia
Fatigue and weakness
Symptoms of rheumatic fever
Weakness, shortness of breath
Symptoms of theumatoid arthritis
Joint pain and deformity
Symptoms of systemic lupus erythematosus
Red rash on face, prolonged fever, weakness, kidney damage, joint pain
Symptoms of ulcerative colitis
Lower abdominal pain
People with glomerulonephritis have what type of autoimmune antibodies?
Kidney cell antigens that resemble streptococcal bacteria antigens
People with graves’ disease have what type of autoimmune antibodies?
Thyroid gland antigens near thyroid-stimulating hormone receptor, causing overactivity
People with type 1 diabetes mellitus have antibodies against?
Pancreatic beta cells
People with hemolyic anemia have antibodies against?
Red blood cells
People with multiple sclerosis have antibodies against?
Myelin in peripheral nerves and in the white mattre of the central nervous system
People with Myasthenia gravis have antibodies against?
Receptors for neurotransmitters on skeletal muscle
People with pernicious anemia have antibodies against?
binding site for vitamin B on cells lining stomach
People with Rheumatic fever have antibodies against?
Heart valve cell antigens that resemble streptococcal bacteria antigens
People with Rheumatoid arthritis have antibodies against?
Cells lining joints
People with systemic lupus erythematosus have antibodies against?
Connective tissue
People with ulcerative colitis have antibodies against!
Colon cells
A virus that breaks down the immune system
HIV
What does HIV stand for?
Human Immunodeficiency virus
HIV May stay silent for years, and then progress to _____; then opportunistic infections begin
AIDS
HIV attacks ________ and then _______
Macrophages; helper T cells
When _________ numbers decline, B cells cannot produce antibodies,
due to lack of cytokine activation
Helper T cell
When Helper T cell numbers decline, ______ cannot produce antibodies,
due to lack of cytokine activation
B cells
In HIV, when Helper T cell numbers decline, B cells cannot produce antibodies, due to lack of ____ activation
cytokine
Later, HIV variants affect _________ cells too
Cytotoxic
An AIDS infected person Person dies from loss of immune response against ______, ______
Pathogens, cancers
How is AIDS transmitted?
Sexual contact, contaminated needles, birth or milk from infected mother, receiving infected blood or tissues from donor
Immune system function declines early in life, as the thymus gland
____ (only 25% as powerful as it once was)
Shrinks
Strength of immune response ________ in elderly people
Decreases
As you age, you develop a Higher risk of infection, cancer, diseases like pneumonia as a person
_____
Ages
As you age, T cell numbers decrease very slightly, and B cell numbers do not
change, but ______ level declines in both types of lymphocytes
Activity
As you age, ____ numbers decrease very slightly, and B cell numbers do not
change, but activity level declines in both types of lymphocytes
T cell
As you age, T cell numbers decrease very slightly, and ____ numbers do not
change, but activity level declines in both types of lymphocytes
B cell
As you age, _______ response to antigens becomes slower
Antibody
Which types of antibodies INCREASE as you age?
IgA and IgG
Which types of antibodies DECREASE as you age?
IgM and IgE
As you age, vaccines may require an extra ____
Dose
As you age, More _______ may be produced, increasing chance of
developing an autoimmune disease
Autoantibodies
Elderly may not be candidates for certain medical treatments that
suppresses _______, such as chemotherapy
Immunity
The respiratory system is Specialized to bring ____ into body, and expel _________
Oxygen; carbon dioxide
The _____ consists of passages that filter, moisten, and warm incoming air and transport it into the body, into the lungs, and to the many microscopic air sacs where
gases are exchanged
Respiratory system
The respiratory system produces ____ sounds
vocal
The _____ system helps with a sense of smell
Respiratory
The respiratory system helps regulate _____
Blood pH
Process of exchanging gases between the atmosphere and body cells
Respiration
Refers to the way an organism acquires energy; oxygen required to produce energy
Respiration
What is required to produce energy during respiration?
Oxygen
Respiration consists of what events?
External, internal and cellular respiration.
Ventilation or breathing; allows gas exchange in lungs
External respiration
Gas transport in blood and exchange with body cells
Internal respiration
Process of ATP production in mitochondria, which uses oxygen
to harness energy and gives off carbon dioxide
Cellular respiration
What are the organs of the respiratory system? Upper and lower tract.
Nose
nasal cavity
sinuses
pharynx
larynx
trachea
bronchial tree
lungs
What are the organs of the UPPER respiratory tract
Nose
Nasal cavity
Sinuses
Pharynx
Larynx
What are the organs of the LOWER respiratory tract?
Trachea
Bronchial Tree
Lungs
_______ provide openings for air to enter and leave nasal cavity
Nostrils (external nares)
Nasal openings are protected from particles by internal ______
Hairs
Hollow space behind the nose
Nasal cavity
The nasal cavity Separated into left and right portions by the _______
Nasal septum
_____________ curl in from lateral walls of the nasal cavity
Nasal conchae (turbinate bones)
Conchae separate nasal cavity into passageways called _________
Meatuses
Upper portion of nasal cavity contains ____________ for sense of smell
Olfactory receptors
The nasal cavity is Lined with what kind of tissue?
Mucous membrane (pseudostratified ciliated epithelium)
In the nasal cavity, Goblet cells produce _____, which traps dust and pathogens
Mucus
What type of cells produce mucus?
Goblet cells
In the nasal cavity, ______ sweep mucus toward pharynx (“mucociliary escalator”), where it is swallowed
Cilia
In the nasal cavity, Cilia sweep mucus toward _____ (“mucociliary escalator”), where it is swallowed
Pharynx
What is the action of cilia sweeping mucus towards the pharynx sometimes called?
Mucociliary escalator
Pathogens and particles from the nasal cavity are destroyed in the ______; prevents infection
Stomach
The nasal cavity Functions in conduction of ___; warms, moistens, and filters incoming
Air
______ support the mucus membrane that lines the nasal cavity, and help increase the mucous membrane’s surface area
Nasal conchae
Air-filled spaces in the maxillary, frontal, ethmoid, and
sphenoid bones of the skull
Sinuses
Where are the sinuses of the respiratory system located?
Maxillary, frontal, ethmoid, and sphenoid
Sinuses open into the?
Nasal cavity
The mucous membrane lining is continuous with the lining of the?
Nasal cavity
What helps to reduce the weight of the skull?
Sinuses
What helps to resonate the voice?
Sinuses
Sinusitis, due to infection or allergic reaction, may result in blockage of sinus drainage, causing sinus pressure and headache
Sinusitis
Respiratory system damage from ________ is slow, progressive, and
sometimes deadly
Smoking
Smoking slows and eventually paralyzes ____, and dirt and pathogens
can no longer be removed from the respiratory system
Cilia
______ occurs when cilia no longer function, excess mucus
is produced, and mucus must be coughed up
Smoker’s cough
Once cilia no longer function due to smoking, pathogens can now access respiratory surfaces, causing more
______
Infections
Coughing leads to?
Chronis bronchitis
Bronchial thickening results in difficulty with?
Expiration
Smoking leads to alveolar walls being destroyed, leading to _______
Emphysema
Once ciliated cells are destroyed from smoking, _______ cells may start dividing, and replacing ciliated cells
Abnormal
_______ develops in 20% of smokers
Lung cancer
____ endangers nonsmokers
ETS (environmental tobacco smoke)
Space posterior to the nasal cavity, oral cavity, and larynx
Pharynx
Passageway for food and air (shared by digestive and respiratory systems)
Pharynx
Which upper respiratory tract organ ____ aids in sound production
Pharynx
What are the three portions of the pharynx?
Nasopharynx
Oropharynx
Laryngopharynx
Superior to soft palate; air passage;
contains openings to auditory tubes
Nasopharynx
Posterior to mouth, inferior to nasopharynx; passageway for food and air
Oropharynx
Inferior to oropharynx; continuous with
larynx and esophagus
Laryngopharynx
An enlargement in the airway superior to trachea, and anterior and
slightly inferior to laryngopharynx
Larynx
Moves air in and out of trachea
Larynx
What are the houses of vocal cords composed of?
a framework of muscles and cartilages bound by elastic tissue
What are the 3 large single cartilages of the vocal cord houses?
Thyroid (adam’s apple)
Cricoid
Epiglottic
What are the 3 pairs of small artilages of the vocal cord houses?
Arytenoid
Corniculate
Cuneiform
Largest vocal cord cartilage, thyroid gland covers lower part
Thyroid (Adam’s apple)
Cartilage below thyroid cartilage
Cricoid
Central portion of flap-like epiglottis
Epiglottic
Regulates vocal cord tension or spech and close larynx for swallowing
Small cartilages
The larynx contains 2 pairs of horizontal ______ composed of muscle and connective tissue
Vocal folds
False vocal cords:
Upper (vestibular) folds
No sound production
Which vocal cords are the upper (vestibular) folds
False vocal cords
Which vocal cords do not produce sounds?
False vocal cords
Which vocal cords help close the airway during swallowing?
False vocal cords
Which vocal cords are the lower folds?
True vocal cords
Which vocal cords produce vocal sounds?
True vocal cords
Which vocal cords create sound as air is forced between them, vibrating them?
True vocal cords
Which vocal cords have an opening between them called the glottis?
True vocal cords
The true vocal cords have an opening between them called the ______
Glottis
Flexible cylindrical tube, 2.5 cm in diameter, 12.5 cm in length
Trachea
Extends downward anterior to the esophagus
Trachea
The trachea is also called the _____
Windpipe
As the trachea enters the thoracic cavity, it splits into left and right _________ at the carina.
Primary bronchi
As the trachea enters the thoracic cavity, it splits into left and right primary bronchi at the ______
Carina
What is the trachea lined with?
Ciliated mucous membrane with goblet cells
Ciliated mucous membrane is also called?
Pseudostratified ciliated columnar epithelium
The wall of the trachea has 20 C-shaped rings of ___________ to prevent collapse of trachea
Hyaline cartilage
A procedure that cuts an opening in the
trachea, to insert a tube for air exchange; done, for example, if an object is lodged in the larynx or trachea
Tracheostomy
The _______ consists of branched airways leading from the trachea to the microscopic air sacs in the lungs
Bronchial tree
The bronchial tree consists of branched airways leading from the _______ to the ____________ in the lungs
Trachea; microscopic air sacs
Starting with the trachea, branching airways resemble an upside-down ____
Tree
Branch from trachea, each leads to
a lung
Right and left main (primary) bronchi
Right and left main (primary) bronchi:
Branch from trachea, each leads to a lung
Branch from main bronchi; 2 on left, 3 on right
Lobar (secondary) bronchi
Lobar (secondary) bronchi:
Branch from main bronchi; 2 on left, 3 on right
Each enters a segment; 8 on left, 10 on right
Segmental (tertiary) bronchi
Segmental (tertiary) bronchi:
Each enters a segment; 8 on left, 10 on right
Each enters a lobule
Intralobular bronchioles
Intralobular bronchioles:
Each enters a lobule
40 to 80 in each lobule
Terminal bronchioles
Terminal bronchioles:
40 to 80 in each lobule
First structures to conduct gas exchange; alveoli
bud from sides of their walls
Respiratory bronchioles:
Respiratory bronchioles:
First structures to conduct gas exchange; alveoli
bud from sides of their walls
Branches of respiratory bronchioles
Alveolar ducts
Outpouchings of alveolar ducts
alveolar sacs
Microscopic air sacs that perform gas exchange; open into sacs
Alveoli
Structure of ________ is similar to trachea, but they contain
cartilaginous plates instead of C-shaped rings
Main bronchi
Structure of main bronchi is similar to trachea, but they contain
________ instead of C-shaped rings
Cartilaginous plates
As bronchi continue to branch, they become _____, and amount of
cartilage decreases
Narrower
As bronchi continue to branch, they become narrower, and amount of
______ decreases
Cartilage
Cartilage disappears in the bronchioles; allows changes in diameter
(________ and __________)
Bronchodilation; bronchoconstriction
_________ becomes more prominent, then begins to diminish from
bronchioles to alveolar ducts, where it disappears
Smooth muscle
Smooth muscle becomes more prominent, then begins to diminish from
bronchioles to _______, where it disappears
Alveolar ducts
As respiratory tubes become thinner, type of ______ changes
Epithelium
What type of epithelium is found in the larger tubes of the respiratory system?
Pseudostratified ciliated columnar epithelium
What type of epithelium is found in the respiratory bronchioles?
Simple cuboidal epithelium
What type of epithelum is found in the alveoli?
Simple squamous epithelium
Why are the alveoli made of simple squamous epithelium?
The alveoli are the sites of gas exchange in the lungs. They use this type of tissue because it is thin and allows gas exchange to take place
Branches of bronchial tree are air passages, _________, but not performing gas exchange
Transporting air
What provides surface area for gas exchange?
Alveoli
Only structure that contain ______ can perform gas exchange
Alveoli
During gas exchange, ____ diffuses through alveolar and
capillary walls to enter the blood
O2
____ diffuses from the blood to alveoli
CO2
Soft, spongy, cone-shaped organs in the thoracic cavity
Lungs
The ____ are separated from each other by heart and mediastinum
Lungs
The right lung has how many lobes?
Three
The left lung has how many lobes?
Two
Region on medial surface of each lung through which
bronchus and large blood vessels enter
Hilum
Double-layered serous membrane surrounding lungs
Pleura
Inner layer of serous membrane; attached
to surface of lung
Pleura
Outer layer of serous membrane; lines
thoracic cavity
Parietal pleura
Potential space between visceral and
parietal pleura
Pleural cavity
A naturally occurring mineral, formerly used in buildings because it resists burning; airborne fibers can lead to scarring of lungs, shortness of breath, lung cancer, mesothelioma (cancer of the
pleura)
Asbestos
An element used in some industrial
applications; in some people, exposure to dust or vapor evokes
immune response that scars lungs and impairs breathing
Berylliosis
Results from long-term exposure to
dust of organic origin; acute form causes fever and breathing
impairment; chronic form changes lungs over time
Extrinsic Allergic Alveolitis
Microfine airborne pollutants can pass through protective mechanisms, and reach alveoli; may worsen asthma, irritate eyes and lungs, increase risk of heart disease and lung cancer
Air pollution
What are some known lung irritants?
Asbestos, berylliosis, extrinsic allergic alveolitis, air pollution
Movement of air from outside
of the body into the bronchial tree and the alveoli
Breathing (or ventilation)
Actions responsible for these air movements are
______ (inhalation), and ______ (exhalation)
Inspiration; expiration
One inspiration + the following expiration = a __________
Respiratory cycle
Force that moves air into the lungs
Atmostpheric pressure
What is the atmospheric pressure at sea level?
760 mm Hg
When respiratory muscles are at rest, atmospheric pressure and
alveolar pressure are ____
Equal
Boyle’s law:
Pressure and volume of gases are inversely proportional.
If pressure inside the alveoli (intra-alveolar pressure) decreases,
_______ pushes air into the airways
Atmospheric pressure
If pressure inside the alveoli (intra-alveolar pressure) decreases,
atmospheric pressure pushes air into the airways. This occurs during normal, resting inspiration (called “_____”), as
the phrenic nerves stimulate the diaphragm to contract downward
Upnea
If pressure inside the alveoli (intra-alveolar pressure) decreases,
atmospheric pressure pushes air into the airways. This occurs during normal, resting inspiration (called “eupnea”), as
the ________ stimulate the diaphragm to contract downward
Phrenic nerves
Volume of thoracic cavity increases, which decreases the
pressure from 760 mm Hg to 758 mm Hg (______)
Boyle’s law
During normal, resting inspiration, the ________ and __________ muscles enlarge the size
of the thoracic cavity
Diaphragm; external intercostal
Lung expansion is aided by surface tension in the ______ cavity
Pleural
_________ reduces surface tension in the alveoli, to help lung
expansion
Surfactant
Maximal (forced, deep) inspiration
Hyperpnea
______ Requires contraction of several other muscles, to enlarge
thoracic cavity even more
Hyperpnea
Which muscles are used during hyperpnea?
Pectoralis minors, sternocleidomastoids, scalenes
During eupnea, _______ of lung tissues and abdominal organs occurs, as
tissues return to their original shape at the end of inspiration
Elastic recoil
During eupnea, _______ develops on the moist surfaces of the alveolar
linings shrinks alveoli
Surface tension
Elastic recoil and surface tension both increase intra-alveolar pressure about 1 mm Hg
above ________________, forcing air out of the lungs
Atmospheric pressure
_____ is a passive breathing process that does NOT involve muscle contraction
Eupnea
Hyperpnea is due to contraction of _________ and abdominal muscles
Internal intercostal
What muscles are involved in hyperpnea?
Rectus abdominis, external oblique, internal oblique, and transversus abdominis
During hyperpnea, increased abdominal pressure orces _______ into a higher position, which pushes more air out of lungs
Diaphragm
Various volumes of air that can be moved into
or out of lungs
Respiratory volumes
Different ________________ in breathing move different volumes of air
in and out of the lungs
Degrees of effort
Measurement of air volumes
Spirometry
Which respiratory volumes can be measured with a spirometer?
Tidal volume (TV)
Inspiratory reserve volume (IRV)
Expiratory reserve volume (ERV)
Which respiratory volumes cannot be measured with a spirometer?
Residual volume (RV)
__________ can be calculated by combining 2 or more
respiratory volumes
Respiratory capacities
_____ capacity (VC) varies with age, gender, body size
Vital
_______ is used to judge progression of respiratory illnesses,
such as emphysema, pneumonia, bronchial asthma, lung cancer
Spirometry
What is the volume in mL for tidal volume (TV)?
500 mL
What is the volume in mL for inspiratory reserve volume (IRV)?
3,000 mL
What is the volume in mL for expiratory reserve volume (ERV)?
1,100 mL
What is the volume in mL for residual volume (RV)?
1,200 mL
What is the volume in mL for vital capacity?
4,600 mL
What is the volume in mL for inspiratory capacity (IC)?
3,500 mL
What is the volume in mL for functional residual capacity (FRC)?
2,300 mL
What is the volume in mL for total lung capacity?
5,800 mL
Volume of air moved in or out of the lungs during a respiratory cycle
Tidal volume (TV)
Maximum volume of air that can be inhaled at the end of a resting
inspiration
Inspiratory reserve volume (IRV)
Maximum volume of air that can be exhaled at the end of a resting
expiration
Expiratory reserve volume (ERV)
Volume of air that remains in the lungs even after a maximal expiratory
effort
Residual volume (RV)
Maximum volume of air that can be exhaled after taking the deepest
breath possible: VC = T V + I RV + E RV
Vital capacity (VC)
Maximum volume of air that can be inhaled following exhalation of resting
tidal volume: I C = TV + lRV
Inspiratory capacity (IC)
Volume of air that remains in the lungs following exhalation of resting tidal
volume: F RC = ERV + RV
Functional residual capacity (FRC)
Total volume of air that the lungs can hold: T LC = V C + RV
Total lung capacity (TLC)
How do you calculate vital capacity (VC)
VC = Tidal volume + Inspiratory reserve volume + Expiratory reserve volume
How do you calculate inspiratory capacity (IC)?
IC = Tidal volume + inspiratory reserve volume
How do you calculate functional residual capacity (FRC)?
FRC = Expiratory reserve volume + residual volume
How do you calculate total lung capacity?
TLC = Vital capacity + Residual volume
Some air entering respiratory tract during breathing does not reach
functional alveoli; these are called?
Dead spaces
Air in respiratory tract that remains in
conduction structures, and does not reach alveoli
Anatomic dead space
Air in respiratory tract that reaches
nonfunctional alveoli, such as alveoli associated with capillaries
with poor blood flow; this occurs occasionally
Alveolar dead space
Total of anatomical and alveolar
dead space
Physiologic dead space
Volume of new atmospheric air moved into respiratory passages each
minute
Minute ventilation
How do you calculate minute ventilation?
MC = tidal volume (TV) x breathing/respiratory rate (RR)
Since some new air in each breath remains in the ___________, another figure can be calculated, to represent actual amount of
inhaled air that reaches the alveoli each minute
Physiologic dead space
Since some new air in each breath remains in the physiologic dead
space, another figure can be calculated, to represent actual amount of inhaled air that reaches the alveoli each minute. This is called?
Alveolar ventilation rate (AVR)
How do you calculate the alveolar ventilaton rate (AVR)?
AVR = Tidal volume (TV) - physiologic dead space (PDS), then multilied by breathing rate
What is the formula for the alveolar ventilation rate (AVR)?
AVR = RR x (TV - PDS)
the volume of air that reaches the alveoli each minute
Alveolar ventilation rate (AVR)
an important value, since it impacts the concentrations of
O2 and CO2 in the alveoli
Alveolar ventilation rate (AVR)
Air movements other than breathing are called
_______ movements
Nonrespiratory
What types of nonrespiratory movements clear the air passages?
Coughing, sneezing
What types of nonrespiratoyr movements express emotions?
Laughing and crying
Allergic reaction to foreign antigens in airway, such as inhaled pollen
Bronchial asthma
During bronchial asthma, In smaller airways, mucus and secretions from allergic response
accumulate, since not many cells are ______
Ciliated
During bonhial asthma, Allergens and secretions irritate smooth muscle, leading to
______ and ______
bronchoconstriction;wheezing
Progressive, degenerative disease in which alveolar walls are destroyed
Emphysema
With emphysema, Clusters of alveoli merge into larger ones, decreasing surface area for _______
Gas exchange
In patients with emphysema, Alveolar walls lose _____, and _______ diminish
Elasticity; capillaries
People with ________Require a lot of muscular effort to breathe
Emphysema
Emphysema is a type of _____ (chronic obstructive pulmonary disease), along with chronic bronchitis
COPD
Normal breathing is a rhythmic, involuntary act that continues even when a person is _______
Unconscious
Groups of ______ in the brainstem control breathing
Neurons
Neurons in thebrainstem that control breathing Initiate impulses that travel on _____ and _____ nerves, causing
inspiration and expiration
Cranial; spinal
What are the two groups of neurons contained within the medullary respiratory center?
Ventral and dorsal respiratory groups
Which respiratory group sets the basic rhytm of breathing?
Ventral respiratory group
Which respiratory group modifies the activity of the ventral group?
Dorsal respiratory group
Which respiratory group helps set the rhythm of breathing by limiting duration of each inspiration?
Pontine respiratory groups
In any mixture of gases, each gas
contributes a portion of the total pressure
Dalton’s law of partial pressure
The concept that theAmount of pressure each gas contributes to the total pressure
Partial pressure
________ are a method of referring to the relative
amounts of gases in a mixture, instead of using concentrations
Partial pressures
Factors that affect the rate and depth of breathing?
- Partial pressure of O2
- Partial pressure of CO2
- H+ concentration in body fluids
- Degree of stretch of lung tissue
- Emotional state
- Level of physical activity
- Receptors include mechanoreceptors and central and peripheral chemoreceptors
What are the main controlling factors that affect the rate and depth of breathing?
PCO2 and H+ ion concentration
Where are the central chemoreceptors located?
In the ventral part of the medulla oblongata
Central chemoreceptors mainly monitor ___ in thebrain
pH
Peripheral chemoreceptors mainly sense changes in blood ____
Po2
Where are the peripheral chemoreceptors located?
Carotid and aortic bodies
Decreased Po2 causes an increase in breathing rate and tidal volume,
leading to an increase in __________
Alveolar ventilation
Usually does not cause a major response, until Po2 decreases to about
50% of normal value
Periperal chemoreceptors
Reflex which helps regulate depth of breathing
Inflation (Hering-Breuer) reflex
As lung tissues stretch during inspiration, ____ receptors are
stimulated
Stretch
During the inflation reflex, Sensory impulses travel over the ____ nerve to respiratory areas
Vagus
Prevents overinflation of the lungs during forced breathing
Inflation (hering-breuer) reflex
Which breathing receptors are stimulated by the stretching of tissues?
Stretch receptors in visceral pleura, bronchioles, and alveoli
Which breathing receptors are stimulated by low plasma PO2?
Chemoreceptors in carotid and aortic bodies
Which breathing receptors are stimulated by high plasma PCO2?
Chemosensitive areas of the respiratory center
Which breathing receptors are stimulated by high cerebrospinal fluid hydrogen ion concentration?
Chemosensitive areas of the respiratory center
What factor stimulates stretch receptors in visceral pleura, bronchioles, and alveoli?
Stretching of tissues
What factor stimulates chemoreceptors in carotid and aortic bodies?
Low plasma PO2
What factors stimulate chemosensitive areas of the respiratory center?
High plasma PCO2
What factors stimulate chemosensitive areas of the respiratory center?
High cerebrospinal fluid hyrogen ion concentration
The stretching of tissues stimulates stretch receptors in the visceral pleura, bronchioles, and alveoli. What is the response?
Inhibits inspiration
Low plasma PO2 stimulates chemoreceptors in carotid and aortic bodies, what is the response?
Increased alveolar ventilation
High plasma PCO2 stimulates chemosensitive areas of the respiratory center, what is the response?
Increased alveolar ventilation
High cerebrospinal fluid hydrogen ion concentration stimulates chemosensitive areas of the respiratory center. What is the response?
Increases alveolar ventilation
the body reacts to the stretching of tissues by inhibiting inspiration. hat is the effect?
Prevents overinflation of lungs during forceful breathing.
The body reacts to low plasma PO2 by increasing aveolar ventilation. What is the effect?
Increased plasma PO2
The body reacts to high plasma PCO2 by increasing alveolar ventilation. What is the effect?
Decreased plasma PCO2
The body reacts to high cerebrospinal fluid hydroen on concentration by increasing alveolar ventilation. What is the effect?
Decreased plasma PCO2
How does the body prevent overinflation of the lungs duringforceful breathing?
The stretching of tissues stimulates stretch receptors in visceral pleura, bronchioles, and alveoli which inhibits inspiration and prevents overinflation of lungs during forceful breathing.
How does the body increase plasma PO2?
Low plasma PO2 stimulates chemoreceptors in carotid and aortic bodies, which increases alveolar ventilation and increases the plasma PO2.
How does the body decrease plasma PCO2?
High plasma PCO2 stimulates chemosensitive areas of the respiratory center, which increases alveolar ventilation and decreases plasma PCO2.
Exercise can greatly increase amount of __ used each minute, and the amount of ___ produced
O2; CO2
During exercise, increased breathing rate would be expected to result
from a decrease in blood ___ and an increase in blood ___
O2; CO2
Although breathing rate does increase during exercise, _____ levels of O2 and CO2 do not change significantly
Blood
During exercise, the breathing rate increases due to: ________ signals respiratory centers to increase breathing rate, when
it signals muscles to contract
Cerebral cortex
During exercise, the breathing rate increases due to: Proprioceptors stimulated by muscular movements stimulate the respiratory
centers to increase breathing rate; called the _______
Joint reflex
Exercise increases demands on both ________ and ________
systems; both systems must keep up with demands
Respiratory; cardiovascular
If shortness of breath occurs during exercise, it is typically due to the cardiovascular
system not moving enough _____ between lungs and body cells
Blood
_____ organs of the respiratory system transport air into and
out of lungs
Tubular
Sites of the vital process of gas exchange between the air
and the blood
Alveoli
Alveoli are sites of the vital process of _________ between the air and the blood
Gas exchange
Microscopic air sacs at ends of alveolar ducts
Alveoli
________ may permit air to pass from one alveolus to
another, providing alternate air pathways
Alveolar pores
_____________ help to clean alveoli
Alveolar macrophages
Most of the wall of an alveolus consists of a layer of ____
cells (type I pneumocytes), _____________ epithelium
Type 1; simple squamous
What type of cells are the walls of alveoli mostly made of?
Type I cells (Type I pneumocytes)
What type of epithelium are most of the wall of an alveolus made of?
Simple squamous epithelium
Part of the wall of an alveolus is made up of what type of cells?
Type II cells; pneumocytes
Part of the wall of an alveolus is made up of type II cells
(type II pneumocytes) that secrete _________
Pulmonary surfactant
Gas exchange between alveolar air and the blood occurs
through the respiratory membrane
Respiratory membrane
What are the three structures of the respiratory membrane?
Alveolar wall
blood capillary wall
fused basement membranes
What type of tissue is the alveolar wall and blood capillary wall of the respiratory membrane made out of?
Simple squamous epithelium
Cell membranes are permeable to _____
Gases
Molecules diffuse from regions of ____ concentration toward regions of
____ concentration
Higher; lower
To determine direction of diffusion of a substance, it is important to know
the ________________
Concentration gradient
In the process of respiration, gases diffuse from areas of _____ partial
pressure to areas of _____ partial pressure
Higher; lower
The respiratory membrane is ___ and gas exchange across it is ___
Thin; rapid
_____ diffusion occurs with greater surface area, shorter
distance, greater gas solubility, and a steeper partial pressure gradient
Increased
______ diffusion occurs due to decreased surface area, harm to
respiratory membrane
Decreased
Driving force for diffusion of O2 and CO2 across the respiratory
membrane is the difference in __________ of the gases
between the alveolus and the capillary
Partial pressures
At high altitude, air is still 21% O2, but Po2 decreases because the
________________ is lower
Atmospheric pressure
In high altitude, Oxygen diffuses more ____ into blood, and ______
saturation declines
Slowly; hemoglobin
In high altitudes, People experience various degrees of ______ sickness
Altitude
Body attempts to obtain more oxygen, by increasing heart and
breathing rate, and increased production of red blood cells and
hemoglobin. This is a result of what?
High altitude
What does HAPE stand for?
High-altitude pulmonary edema
What IS HAPE?
Severe form of altitude sickness
Sudden severe headache, nausea, vomiting, rapid heart and breathing rate,
cyanosis are all symptoms of?
HAPE
What are four disorders that impair gas exchange?
- Pneumonia
- Tuberculosis
- Atelactasis (lung collapse)
- Acute respiratory distress syndrome
Infection of the lungs, in which alveoli swell due to edema
Pneumonia
in ______, Alveoli become abnormally permeable; fluids and WBCs enter alveoli.This decreases available surface area for gas exchange.
Pneumonia
Bacterial lung infection, in which dense connective tissue “tubercles” form around
infection sites, to wall off infection, and stop the spreading
Tuberculosis
In patients with ______, lung tissue is destroyed, and respiratory membrane thickens as tubercles form,
reducing surface area for gas exchange
Tuberculosis
In ______, Blood vessels collapse along with the lung. In case of obstruction, alveoli beyond obstruction collapse. Usually, the functional regions carry on enough gas exchange for cells.
Atelectasis (lung collapse)
Form of atelectasis, in which alveoli collapse. Blood vessels and airways narrow, and O2 delivery is severely impaired.
Acute respiratory distress syndrome
What transports O2 and CO2 between the lungs and the
body cells?
Blood
As ______ enter the blood, they dissolve in the plasma
or chemically combine with other substances
Gases
As ______ enter the blood, they dissolve in the plasma
or chemically combine with other substances
Gases
As ______ enter the blood, they dissolve in the plasma
or chemically combine with other substances
Gases
As ______ enter the blood, they dissolve in the plasma
or chemically combine with other substances
Gases
98% to 99% of O2
diffuses into alveolar capillaries, enters red blood cells, and binds to
_____
Hemoglobin
O2 loosely binds to Fe in heme unit of each of 4 polypeptide chains in hemoglobin,
forming _________ (1 hemoglobin can bind to 4 O2)
Oxyhemoglobin
Chemical bonds between O2 and hemoglobin are relatively ______
Unstable
The other 1% to 2% of O2 dissolves in the _______
Blood plasma
What are the factors which increase the release of O2 from hemoglobin?
- Decrease in PO2
- Increase in PCO2
- Increase in acidity
- Increase in temperature
Released O2 moves from _____ into _____
Blood; tissues
About 75% of the O2 remains bound to hemoglobin in _____ blood, ensuring that respiratory system can adjust CO2 levels and pH as necessary
Venous
______ differences cause oxygen to diffuse from
an alveolus into the blood
Partial pressure
Blood is ______-rich, 100% saturated, in pulmonary
capillaries
Oxygen
Oxygen is transported through the blood, bound to _______
Hemoglobin
Differences in ___ cause O2 to diffuse from the blood into the fluid around the cells
PO2
After dropping off O2 to tissues, hemoglobin is still about 75% saturated in venous blood; this is called _________
blood
Oxygen-poor
As the ____ increases, so does the amount of O2 released from oxyhemoglobin
PCO2
As ____ decreases (as acidity increases),
the amount of O2 released from oxyhemoglobin increases
Blood pH
As blood ______ increases,
amount of oxygen released from oxyhemoglobin increases
Temperature
Cellular metabolism generates ____
CO2
Why does CO2 diffuse into capillaries instead of tissues?
Because tissues have a higher Pco2 than the capillaries
What are the three ways CO2 is transported to the lungs?
Dissolves in plasma (7%)
Carbaminohemoglobin (23%)
As part of a bicarbonate ion (70%)
How is the majority of CO2 transported to the lungs?
As part of bicarbonate ion (70%)
Upon reaching the lungs, bicarbonate ions diffuse back into the ____s, and the reaction runs in reverse.
RBC
CO2 diffuses from blood
into alveoli, from which it is exhaled from the _____
Lungs
As we age, ______ epithelial cells become fewer in number
Ciliated
As we age, cilia become less ____
Active
As we age, mucus ______
Thickens
As we age, swallowing, gagging, and coughing reflexes ____
Slow
As we age, Macrophages in the lungs lose _______
Efficiency
As we age, we develop An increased susceptibility to respiratory _______
Infections
As we age, _________ may require more effort, as costal cartilage stiffens, and
postural changes change shape of thoracic cavity
Breathing
As we age, Connective tissue replaces muscle in bronchioles, hindering ________
Dilation
As we age, Bronchial walls ____ and do not open as much
Thin
As we age, alveolar walls thin, and alveoli merge, decreasing __________ area
Gas exchange
List the correct order for air flow, with the more proximal airway at the top of the list and the most distal airway at the bottom
- Main brnochus
- Lobar bronchus
- Segmental bronchus
- Intralobular bronchiole
- Terminal bronchiole
- Respiratory bronchiole
What is the role of the dorsal respiratory group in the control of respiration?
Stimulateste expiratory muscles
Which respiratory control center influences the rhythm of breathing by limiting inspiration?
Pontine respiratory group
Where does internal respiration occur?
at the capillary networks of the body tissues
The respiratory system provides ______ for aerobic reactions and eliminates ______ at the appropriate rate to maintain the pH of the internal environment.
oxygen; carbon dioxide
List four characteristics of the dorsal respiratory group (DRG).
stimulates the diaphragm
modifies function of ventral respiratory group
located in the medulla oblongata
integrates sensory information about the respiratory system
List two characteristics of the pontine respiratory group.
located in the pons
influences the basic rhythm of breathing by limiting inspiration
The exchange of gases (O2 and CO2) that occurs in the tissues between capillary blood and the tissue fluid is called ______.
internal respiration
We breathe in order to take in ______ and release ______.
oxygen; carbon dioxide
As air passes over the mucous membrane lining the nasal cavity,
________ radiates from the blood and warms the air. Evaporation of
_______ from the mucus membrane moistens the air.
Heat/water
What is the role of the dorsal respiratory group in the control of respiration?
stimulates inspiratory muscles
