Lecture Exam Review: Biology - Lymphatic/Immune System PDF

Things to know/review for Lecture Exam #3 Chapter 22: Lymphatic/Immune Systems List the parts of the lymphatic system. Lymph (fluid portion) Lymphatic vessels Lymphatic nodules Lymph nodes Tonsils Spleen Thymus...

Things to know/review for Lecture Exam #3 Chapter 22: Lymphatic/Immune Systems List the parts of the lymphatic system. Lymph (fluid portion) Lymphatic vessels Lymphatic nodules Lymph nodes Tonsils Spleen Thymus Red Bone Marrow Describe the structure of lymphatic vessels. Lymphatic Capillaries o More PERMEABLE than blood capillaries o Epithelium functions as series of ONE-WAY VALVES o Found in ALL-PARTS of the body EXCEPT … ▪ NERVOUS SYSTEM ▪ BONE MARROW ▪ TISSUES without BLOOD VESSELS(cartilage, cornea, epidermis) Lymphatic vessels o Have valves that ensure one-way flow o Structure like small veins o Route used by pathogens/cancer cells Explain how lymph transported through lymphatic vessels. Capillaries Trunks Thoracic duct Right lymphatic duct: Drains part of body that is not drained by the right Drains right lymphatic duct side of o Head Cisterna chyli o Upper o Enlarged sac in limb abdominal area o Thorax which collects lymph  Junction of Jugular and Subclavian veins Distinguish between lymphatic tissue and a lymphatic organ - primary and secondary (where is it found and what is the function) Lymphatic ORGANS contain Lymphatic TISSUE (lymphocytes, macrophages, dendritic cells, reticular cells, and other cell types) Primary Where immune cells mature and become immunocompetent Red bone marrow thymus Secondary Mature lymphocytes encounter ANTIGENS and are activated Nodes Spleen Nodules (tonsils, Peyer’s patch, appendix) Lymphatic tissue DOES NOT have a Connective tissue capsule; organs are encapsulated Describe the structure and function of lymphatic tissue and a lymphatic organ. Lymphatic Organ o Primary ▪ Thymus bilobed gland in superior mediastinum. Lobes surrounded by capsule with Trabeculae extend into gland dividing it into lobules. Internal framework of epithelial cells ▪ Cortex densely packed and rapidly dividing lymphocytes macrophages and dendritic cells ▪ Medulla fewer lymphocytes but has thymic corpuscles involved in development of regulatory T (Treg ) cells Treg cells o prevent autoimmunity ▪ Thymus secrets thymosin Important in T cell development o Secondary ▪ naïve lymphocyte encounter antigens (pathogen) and are activated ▪ Common structures Reticular fibers o Associated with fixed macrophages germinal centers o Sites of formation of lymphocytes o Cells are rapidly dividing Specialized post-capillary vessels o allow cells from the blood to directly enter these tissues ▪ Organs Lymph nodes o Principal secondary lymphoid organs o Filters lymph and activates immune cells o Prominent clusters: o Round/bean-shaped structures 1 to 25 mm long o responsible for filtering lymph with external fibrous capsule ▪ Large lymphatic capillaries crisscrossing reticular fibers (Macrophages reside on fibers) o Capsules extend inward as trabeculae o Substances removed by phagocytosis or stimulate lymphocytes to proliferate in germinal centers o Two histologically distinct regions of node ▪ Cortex ▪ Medulla o Circulation o Lymph enters afferent lymphatic vessels o Through cortex which has germinal center and then to medulla which has cords of B cells and plasma cells o Exits at hilum via efferent lymphatic vessels o Homeostatic imbalance o Buboes: ▪ Swollen “glands” ▪ Sometimes pus-filled ▪ Bubonic plague o Lymph nodes  ▪ secondary cancer sites ▪ Cancer cells often migrate to lymph nodes Trapped and proliferate ▪ Can move from lymphatic system to circulatory system spreading cancer through body. Spleen o Blood-rich organ about the size of fist o Located lateral on left side of stomach o Largest lymphoid organ o Served by splenic artery and vein, enter/ exit at hilum o Encased by fibrous capsule and has trabecula o Function ▪ Destroys defective RBCs. ▪ Detects and responds to foreign substances. ▪ Limited reservoir for blood. o Blood flows through 3 different rates o Slow flow is via open circulation o White pulp ▪ mainly immune function ▪ Surrounds central arteriole ▪ Location of B cells & T cells o Red pulp ▪ old blood cell+ bloodborne pathogens destroyed ▪ Reticular fibers ▪ Macrophages engulf RBC o o Slow flow is via open circulation Nodules o denser aggregations. o Numerous in loose connective tissue of digestive (Peyer’s  patches), respiratory, urinary, o Found in areas routinely exposed to environmental pathogens ▪ M.A.L.T (Mucosa- associated lymphoid tissue) Lymphoid tissues associated with mucous membranes Tonsils Peyer’s Patch Appendix ▪ B.A.L.T (Bronchus- associated lymphoid tissue) effective against inhaled pathogens Lymphatic Tissue o MALT ▪ Tonsils Large groups of lymphatic nodules in nasopharynx and oral cavity. Simplest of lymphoid organs Epithelium form tonsillar crypts Major function - Help children’s bodies recognize, destroy pathogens and develop immunity Form a ring around the border between the oral cavity and the pharynx. Groups o Palatine (the “tonsils”), posterior oral cavity - largest, most often infected o Pharyngeal (the “adenoids”), posterior wall of nasopharynx o Lingual, base of tongue ▪ Peyer’s Patch Dome-shaped structures of dense cluster of lymphocytes found underlying the mucosa found in the ileum o functions of Location ▪ Destroy bacteria, preventing intestinal wall breach ▪ Generate “memory” lymphocytes in adaptive immunit ▪ Appendix offshoot of cecum  Function not really known but believe to play role as secondary immune organ Storage for good bacteria and repopulates the digestive system after bouts of diarrhea o BALT ▪ Lymphoid follicular structures with an overlying epithelial layer found along the bifurcations of the bronchi ▪ Less-organized structure than other lymphoid nodules but still are dense cluster of lymphocytes ▪ Effective against inhaled pathogens Define the concepts of specificity and memory as they apply to immunity. Specificity o Related to the adaptive immune system o Recognizes and targets specific antigens Memory o Stronger attack to known antigens on second and subsequent Distinguish between general characteristics of innate immunity and adaptive immunity. Adaptive immunity o Third line of defense o Two main branches ▪ Cellular (cell-mediated) immunity Lymphocytes -T-Cells o Directly o Indirectly Cellular targets ▪ Humoral (antibody- mediated) immunity Antibodies produced by B-cells Bind to target cell Extracellular targets o Specific defensive system ▪ Eliminates almost any pathogen or abnormal cell o Must be primed to initial exposure o Characteristics ▪ Specific: recognizes and targets specific antigens ▪ Memory: stronger attack to “known” antigens on second subsequent exposures o Stimulates ▪ Antigens – large molecules Foreign o Not produced by the body o Introduced from the outside o Bacteria, viruses, other microorganisms that cause disease o Pollen, animal dander, feces of mites, foods, drug cause overreaction of immune system (ALLERGIC REACTION) ▪ Self-antigens: produced by body  Innate immunity o First line of defense+ Second line of defense ▪ Includes physical barriers (ex: skin, mucous membranes) and internal defenses (ex: phagocytosis, natural killer cells o Broad response ▪ Targets wide range of pathogens using generalized mechanisms such as inflammation and phagocytosis o Limited specificity o Uses pattern recognition receptors (ex: toll-like receptors) to detect common pathogen-associated molecular patterns (PAMPS) Difference between innate and adaptive immunity Innate immunity o Rapid and general (non- specific) response Adaptive immunity o Very specific but takes longer to establish Describe the components of innate immunity. Surface barriers (1st Line of Defense) o Physical barriers ▪ Prevent microbes and chemicals from entering the body ▪ Skin, mucous membrane Keratin o Resistant to ▪ Acid/bases ▪ Bacterial enzymes ▪ Toxins ▪ Tears, saliva, urine Lysozyme o Enzyme that destroys bacteria by digesting cell wall ▪ Cilla in respiratory tract ▪ Coughing and sneezing ▪ Protective chemicals that inhibit or destroy microorganisms Sweat Saliva Tears Acid  Mucus Internal defenses (2nd Line of Defense) o Triggered by the surface barriers breached by nicks or cuts o Internal group of cells and molecules activated ONLY if deep tissues are invaded o Phagocytes ▪ Important and effective mechanism of swallowing and destroying pathogens during innate immune response Phagosome joins lysosome Digestive enzymes, effectively killing many pathogens ▪ White blood cells that ingest foreign invaders(pathogen) Neutrophils Macrophages (differentiate from monocytes) ▪Some pathogens not killed with acidified lysosomal enzymes (eg: tuberculosis bacteria) ▪ Helper T cells trigger respiratory Rapid release of free radicals or reactive oxygen species Increasing pH and osmolarity + kills bacteria ▪ Macrophages Develop form monocytes that leave blood -> enter tissue Longer-lived than neutrophils Can ingest larger particles (Can become Dendritic cells) Chief phagocytic cells Free macrophages: wander Fixed macrophages: permanent residents in some organs Go by many names: o Kupffer cells in liver o Histiocytes in connective tissues o Alveolar macrophages in lungs o Microglia in CNS ▪ Neutrophils Attracted via chemotaxis Granules contain mediator proteins (such as histamine) Most abundant WBC but become phagocytic on exposure to infectious material o NK cells ▪ Main function is immunological surveillance or policing blood and lymph ▪ Attack cells that lack “self” cell- surface receptors (MHC1) ▪ Kill by inducing apoptosis (cell death) in cancer cells and virus- infected cells ▪ Attaches to cells via activation receptor (Fas ligand) then sends apoptotic signals ▪ Secrete chemicals Perforin o Forms pores in membranes of infected cells Granzyme o Protein-digesting enzyme o Soluble Mediators ▪ Proteins that play a role in the regulation (control) of an immune  reaction ▪ Can be initiating, perpetuating, or aggravating ▪ Messengers Cytokine: molecule that allows cells to communicate with each other over short distances Chemokine: similar to cytokine but function to attract WBC (chemotaxis) from longer distances towards the source (ie injured tissue) ▪ Most important antimicrobial proteins Interferons o Induced proteins o Travel to adjacent cells and gives notice of viral infection Complement proteins o Bind to membrane of the pathogen labeling it for phagocytosis (opsonization) o Act as chemokine to attract phagocytes o Form damaging pores in membrane of pathogen o Inflammation ▪ Sign that innate response has been triggered ▪ Triggered by body tissues injured or infection ▪ Benefits Prevents spread of damaging agents Disposes of cell debris and pathogens Alerts adaptive immune system Sets the stage for repair ▪ Acute Short term inflammatory response Can become chronic ▪ Chronic Ongoing inflammation Caused by foreign bodies Persistent pathogens and auto immune disease ▪ Stages of inflammation o Tissue injury ▪ Inflammatory chemical release ▪ Chemicals released Histamine Leukotrienes Prostaglandins Causing o Vasodilation o leaky capillaries o attract leukocytes to area o Vasodilation and increased permeability ▪ Blood flow to area increases ▪ Fluid containing clotting factors and antibodies flood area (edema) ▪ Fluid sweeps foreign material into lymphatic vessels ▪ Clotting factors form fibrin mesh, begins repair  ▪ Pressure on nerve endings = pain o Phagocyte mobilization ▪ Leukotrienes attract NEUTROPHILS ▪ Neutrophils flood area first ▪ macrophages follow ▪ phagocyte and pathogen subsequently die ▪ accumulated is visible as pus ▪ Complement proteins activated if pathogen involved ▪ Adaptive immunity elements arrive ▪ o Fever ▪ Abnormally high body temperature ▪ Systemic response ▪ Leukocytes and macrophages secrete pyrogens ▪ Pyrogens: Hypothalamus raises temperature Liver and spleen sequester iron/zinc Increases metabolic rate increases rate of repair Describe how chemical mediators are involved with immunity. Cytokines o Act as signaling proteins released by immune cells (e.g., macrophages, T cells) to regulate inflammation, immune cell activity, and communication. Chemokines o A subset of cytokines that guide the movement of immune cells toward areas of infection or injury. o Histamine o Released by mast cells and basophils during allergic reactions and in response to injury. Prostaglandins and Leukotrienes o Lipid-based mediators produced at infection or injury sites. o Enhance inflammation o Increase pain sensitivity o Cause for fever by stimulating blood flow to the area o Assisting in immune cell treatetment Antibodies o Produced by B cells in response to specific antigens. Complement Proteins o A group of blood proteins that enhance immune defense when activated. List the types of white blood cells involved in innate immunity. Neutrophil o Attracted via chemotaxis o Granules contain mediator proteins (such as histamine) o Most abundant WBC but become phagocytic on exposure to infectious material Monocytes o Develop form monocytes that leave blood -> enter tissue o Longer-lived than neutrophils  o Can ingest larger particles (Can become Dendritic cells) o Chief phagocytic cells o Free macrophages: wander o Fixed macrophages: permanent residents in some organs Dendritic Cells o Found in tissues that are in contact with the external environment, like the skin and mucous membranes. o Antigen presenting cell o Present antigens to T cells in lymph nodes o Most effective presenter (links innate and adaptive immunity) NK Cells ▪ Main function is immunological surveillance or policing blood and lymph ▪ Attack cells that lack “self” cell- surface receptors (MHC1) ▪ Kill by inducing apoptosis (cell death) in cancer cells and virus-infected cells ▪ Attaches to cells via activation receptor (Fas ligand) then sends apoptotic signals ▪ Secrete chemicals Perforin o Forms pores in membranes of infected cells Granzyme o Protein-digesting enzyme Eosinophils o attracted to site by T cell cytokines. o Mast cell degranulation (inflammation) o fluid leakage o caused by the increase in local vascular permeability thought to have a flushing action List the events of the inflammatory response and explain their significance. ▪ Stages of inflammation o Tissue injury ▪ Inflammatory chemical release ▪ Chemicals released Histamine Leukotrienes Prostaglandins Causing o Vasodilation o leaky capillaries o attract leukocytes to area o Vasodilation and increased permeability ▪ Blood flow to area increases ▪ Fluid containing clotting factors and antibodies flood area (edema) ▪ Fluid sweeps foreign material into lymphatic vessels ▪ Clotting factors form fibrin mesh, b’egins repair ▪ Pressure on nerve endings = pain o Phagocyte mobilization ▪ Leukotrienes attract NEUTROPHILS  ▪ Neutrophils flood area first ▪ macrophages follow ▪ phagocyte and pathogen subsequently die ▪ accumulated is visible as pus ▪ Complement proteins activated if pathogen involved ▪ Adaptive immunity elements arrive What is the respiratory burst? Triggered by Helper T cells Rapid release of free radicals or reactive oxygen (ROS) Increasing pH and osmolarity and kills bacteria Define antigen. Any substance that causes the body to make an immune response against that substance Describe the two groups of antigens…foreign and self Foreign o Not produced by the body o Introduced from the outside o Bacteria, viruses, other microorganisms that cause disease o Pollen, animal dander, feces of mites, foods, drug cause overreaction of immune system (ALLERGIC REACTION) Self o produced by body Describe the origin, development, activation, and proliferation of lymphocytes (T and B cells) Origins Develop Which cells recognized them (CD4/CD8) CD4 o Helper function T-cells o Recognized antigens from MHC class II CD8 o Cytotoxic function T- cells o Recognized antigens from MHC class I Describe the function of major histocompatibility complex (MHC) molecules. Group of self-proteins Unique to everyone Groove holds self-antigen or foreign antigen o Association of antigen and MHC occurs inside cell o T cell recognize antigens presented on MHC proteins Distinguish between MHC class I molecules and MHC class II molecules. MHC class I o Displayed by all cells except RBCs o Endogenous antigen (virus, parasites, bacterias that replicate inside the cell) o Activate CD8 T cells MHC class II o displayed by APCs (dendritic cells, macrophages, & B cells) ▪ Exogenous antigen (pathogens found outside cells ▪ Activate CD4 T cells Define antibody-mediated immunity and name the cells involved.  Humoral (antibody- mediated) immunity o Antibodies produced by B-cells o Bind to target cell o Extracellular targets Cells involved o B cells o Plasma cells o Memory B cells o Helper T cells (CD4) o Dendritic Cells o Macrophages Define cell-mediated immunity and name the cells involved. Cellular (cell-mediated) immunity o Lymphocytes -T-Cells o Directly o Indirectly o Cellular targets Cells involved o CD8+ T Cells (Cytotoxic T Cells): o D4+ T Cells (Helper T Cells, specifically Th1 subset): o Macrophages o Natural Killer (NK) Cells o Dendritic cells o Memory T cell Know the 5 difference types of antibodies and their function IgM o Receptor on surface of B-cells o LARGEST Antibodies o very effective o Main in primary response o Activates complement protein cascade IgD o Receptor on surface of B cells IgG o Most common antibody o Main in secondary response o Crosses placenta to protect fetus IgA o Secreted in mucus, saliva, and tears o ONLY antibody to LEAVE interior to protect body surfaces IgE o Cause release of histamine o Associated with allergies Describe the functions of the ssddifferent antibodies. IgM o Receptor on surface of B-cells o LARGEST Antibodies o very effective o Main in primary response o Activates complement protein cascade IgD o Receptor on surface of B cells IgG  o Most common antibody o Main in secondary response o Crosses placenta to protect fetus IgA o Secreted in mucus, saliva, and tears o ONLY antibody to LEAVE interior to protect body surfaces IgE o Cause release of histamine o Associated with allergies Discuss the primary and secondary responses to an antigen and explain the basis for long-lasting immunity. Primary immune response o First time exposure ▪ Lag period: 3 to 6 days ▪ Levels peak in 10 days Secondary immune response o Re-exposure o Faster, more prolonged, more effective o Respond within hours, not days o Antibodies bind with greater affinity o Antibody level can remain high for week to months Describe the types and functions of T cells. Explain the ways that adaptive immunity can be acquired (active and passive) Active o Contact o Naturally acquired ▪ Infection; contact with pathogen o Artificially acquired ▪ Vaccine; dead or attenuated pathogens Passive o No contact o Naturally acquired ▪ Antibodies passed from mother to fetus o Artificially acquired ▪ Antibodies injected What is edema? Swelling caused by too much fluid trapped in the body tissues Immune system disorders Immunodeficiencies o Congenital (genetic) or acquired conditions that impair function or production of immune cells o Severe combined immunodeficiency (SCID) syndrome: ▪ A combination of genetic defects affecting B and T cells o Treatment: bone marrow transplant AIDS (acquired immunodeficiency syndrome) o Infection by the human immunodeficiency virus (HIV) o HIV interferes with helper T cells o Virus uses CD4 receptor to enter cell  o High mutation rate of virus results in resistance to drugs o Initial immune response produces anti bodies with flu-like symptoms in first 1-2wk o Seroconversion defers AIDS until immune system collapses o Four known individuals have been cured due to stem cell transfusion which contained cells with genetic mutation of the CCR5 gene Hypersensitivities o immune responses to harmless threat causing tissue damage o Different types: ▪ Type I Immediate happens rapidly and can be systemic (anaphylactic shock) treated with anti-histamine or epinephrine ▪ Type II + III Slow onset: 1-3 hours blood transfer ▪ TYPE IV Delayed Slow onset 1–3 days i.e. tuberculosis, poison ivy Auto immune diseases o when immune system loses ability to distinguish self from foreign o Examples ▪ Rheumatoid arthritis: immune system attacks ▪ Multiple sclerosis: destroys white matter myelin ▪ Graves’ disease: causes hyperthyroidism ▪ Type 1 diabetes: attack pancreatic beta cells ▪ Glomerulonephritis: damages kidney o Treatment: suppress immune system Chapter 23: Respiratory System List the structures that comprise the respiratory system. External nose – for air inspiration Nasal cavity o Clean +warm o Humidify air Pharynx o Common passageway for food + air Larynx o VOICE BOX o Keeps airway patent o Division of upper and lower respiratory system  Trachea o Air cleaning tube into lungs Bronchi o TUBE o Directs air into lungs Lungs o Network of aveoli Describe the structural and function anatomy of the respiratory system. Pulmonary ventilation o Aka breathing o Moving air IN and OUT of lungs Gas Exchange o Diffusion of gases across plasma membranes o Two types: ▪ Pulmonary External gas exchange Gas exchange between air in LUNG (specifically in ALVEOLI) + BLOOD ▪ Tissue Internal gas exchange Gas exchange between BLOOD and TISSUES Transport o Oxygen and Carbon Dioxide moving through the bloodstream Regulation of blood pH o Regulation of hydrogen(H) Production of chemical T issue o ACE = enzyme involved in blood pressure regulation Voice production o Movement of air past vocal folds Olfaction o Airborne molecules drawn into nasal cavity Protection o Against microorganisms by ▪ Preventing entry ▪ Removing them from respiratory surfaces Upper and lower respiratory tracts further divided into conducting zone and respiratory zone o Conducting zone ▪ Conduits that transport gases (nose -> small air tubes in lungs strictly for pulmonary ventilation) ▪ Includes ALL respiratory structures EXCEPT the alveoli sac o Respiratory zone ▪ Site of gas exchange ▪ Alveoli sac  Know the structure of the larynx and role of epiglottis and vocal chords Larynx o The voice box o Attached to HYOID BONE o Composed of 8 hyaline, 1 elastic cartilage (EPIGLOTTIS) o Home of the vocal cords o Epithelium o Continuous with trachea Thyroid cartilage o Part of larynx o Large, shield-shaped cartilage o Laryngeal prominence (ADAM’S APPLE) Epiglottis o Part of larynx o Attached to thyroid cartilage o Covers larynx inlet Describe the anatomy of the respiratory passages, beginning at the nose and ending with the alveoli. Nose and Paranasal Sinuses o Nose = ONLY external portion o Functions of nose ▪ Provides an airway ▪ Moistens/warms air ▪ Filters/cleans air ▪ Resonating chamber of speech ▪ Houses olfactory receptors o Structures of nose ▪ Root (Area between eyebrows) ▪ Bridge + Dorsum nasi (Anterior margin) ▪ Apex (tip of nose) ▪ Alae (Lateral boundary) Nasal Cavity o Formed by nasal and frontal bones superiorly o Formed by Maxillary bones laterally o Plates of hyaline cartilage o Divided nasal septum ▪ Anteriorly – septal cartilage ▪ Posteriorly – vomer bone and perpendicular plate o Posterior nasal opening ▪ Where nasal cavity turns into nasopharynx o Nasal vestibule ▪ Superior to nostrils ▪ Lined with hairs that filter coarse particles o Mucous membranes ▪ Contain lysozyme and defensins ▪ Ciliated cells sweep mucus towards throat ▪ Inhaled air warmed by capillaries ▪ Mucosa contains sensory nerve endings that triggers sneezing reflex o Nasal conchae  ▪ Mucosa -covered projections ▪ Superior, middle, and inferior conchae ▪ Shape helps Increase mucosal area Enhance air turbulance ▪ Function Filter Heat, and moisten air going in Reclaim heat and moisture Paranasal Sinuses o Cavities surrounding nasal cavity ▪ Frontal, sphenoid, ethmoid, and maxillary bones ▪ Functions Lighten skull Secrete mucus Help to warm and moisten air The Pharynx o Muscular tube “throat” ▪ Connects nasal cavity and mouth to larynx and esophagus ▪ Composed of skeletal muscle o Three regions ▪ Nasopharynx ▪ Oropharynx ▪ Laryngopharynx o Common opening for digestive and respiratory systems o Nasopharynx ▪ Lies posterior to nasal cavity ▪ Pseudostratified columnar epithelium with goblet cells ▪ Mucous debris is allowed ▪ Uvula close nasopharynx during swallowing ▪ Pharyngeal tonsils(adenoids) – located on posterior wall ▪ Auditory(eustachian) tubes Drain and equalize pressure from middle ear + open into lateral walls How pathogen from cold causes ear infection o Oropharynx ▪ Shared with digestive system ▪ Lined with most stratified squamous epithelium ▪ Passageway for food and air ▪ Stratified squamous epithelium ▪ Fauces opening that connect oral cavity and pharynx ▪ Palatine tonsils on lateral walls of fauces ▪ Lingual tonsil on posterior surface of tongue o Laryngopharynx ▪ Passageway for food and air  ▪ Stratified squamous epithelium ▪ Posterior to epiglottis ▪ Extends to larynx (anteriorly) + esophagus(posteriorly) The Larynx o The voice box o Attached to HYOID BONE o Composed of 8 hyaline, 1 elastic cartilage (EPIGLOTTIS) o Home of the vocal cords o Epithelium o Continuous with trachea o Thyroid cartilage ▪ Large, shield -shaped cartilage ▪ Laryngeal prominence (Adam’s apple) o Epiglottis ▪ Attached to Thyroid cartilage ▪ Covers larynx inlet during swallowing ▪ Covered in taste bud- containing mucosa o Functions of larynx ▪ Provides patent (open and unobstructed) airway ▪ Routes air and food into proper vessel ▪ Voice production o Vocal folds ▪ Glottis Folds and opening between vocal folds ▪ True vocal cords Elastic fiber that fold to form Folds vibrate to produce sound ▪ Vestibular folds False vocal cords Close glottis during swallowing The Trachea o Trachealis ▪ Smooth muscle fibers, connect posterior parts of cartilage rings ▪ Contracts during coughing o Crania ▪ Last tracheal cartilage that branches into two main bronchi ▪ Mucosa of carina highly sensitive Violent coughing if foreign objects makes contact The Bronchi and Subdivisions o Bronchial tree ▪ Collective term used for multiple-branched bronchi ▪ Trachea divides into right and left primary bronchi (bronchus singular) ▪ Branches into lobar: 3 on right, 2 on left o Bronchi and bronchioles capable of changing diameter: ▪ Bronchodilation: smooth muscle relaxes decreased resistance so airflow increases.  Bronchoconstriction: smooth muscle contracts ▪ Increased resistance so airflow decreases. o Branches into segmental bronchi o Branches become smaller and smaller until becoming terminal bronchioles - 1000 each lung o Asthma attack Respiratory Zone o Alveolus (alveolar sac = cluster) ▪ Walls w/ 2 type of cells Type I pneumocytes o Thin squamous epithelial cells o 90% of surface of alveolus. o Gas exchange Type II pneumocytes o Round or cube shaped secretory cells o Produce surfactant and antimicrobial proteins ▪ Alveolar pores connect adjacent alveoli, equalize pressure ▪ Alveolar macrophages keep alveolar surfaces sterile State the parts of the respiratory membrane Respiratory membrane o Alveoli + Capillary o 0.1-0.5 um thick o Blood air barrier o Gas exchange Explain the role of the thoracic wall in respiration. Protects lungs and heart Supports chest expansion/contraction Attachment for respiratory muscles Moves ribs (pump-handle & bucket-handle) Changes thoracic cavity volume Enables air pressure regulation for breathing Describe the structure of the lungs Root Coastal Surface Apex Base Right lung Left lung Superior, middle, and inferior Superior and inferior lobes lobes Oblique fissure Horizontal fissure Smaller than right Oblique fissure Lobes divided into bronchopulmonary segments  o 10 on right o 8–10 on left o Separated by connective tissue septa o Each segment has own artery, vein, and bronchus Muscles of respiration. Change volume of the thoracic cavity Allowing air to flow in and out of the lungs Muscle of inspiration o INCREASE volume of cavity o Diaphragm o External Intercostals o Pectoralis minor o Scalene muscles Muscle of expiration o DECREASE volume of cavity o Internal intercostals o transverse thoracic o assistance from o abdominal muscles. Mechanics of inspiration & expiration (quite and forced) Inspiration o Eupnea=quiet breathing o Involving diaphragm and external intercostals 1. Diaphragm contracts Increase thoracic volume 2. External intercoastal muscle contracts Rib cage lifted and out Increase in thoracic volume o Steps 1. Inspiratory muscles contract 2. Thoracic cavity volume increases 3. Lungs are stretched 4. Intrapulmonary volume increases 5. Intrapulmonary pressure drops 6. Air flows into lungs down its pressure gradient until intrapulmonary pressure is ATM o Forced o Hyperpnea o Accessory muscles activated ▪ Scalene ▪ Sternocleidomastoid ▪ Pectoralis minor ▪ Erector spinae Muscle straighten thoracic ▪ Increase thoracic cage size further than normal, creates a larger pressure gradient, more air drawn in Expiration o Passive process 1. inspiratory muscles relax 2. Thoracic cavity volume decreases 3. Volume decrease 4. Lung’s recoil o Steps  1. Inspiratory muscles relax 2. Thoracic cavity volume decreases 3. Elastic lungs recoil passively 4. Intrapulmonary volume decreases 5. Intrapulmonary pressure rises 6.Air (gases) flows out of lungs until intrapulmonary pressure equals ATM o Force expiration ▪ Active process that uses oblique and transverse abdominal muscles Explain partial pressure and its relationship to the concentration of gases in the body. Partial pressure o Proportional to its percentage in mixture o Greater partial pressure difference between 2 areas = more rapid movement of gas  Understand how changes in alveolar pressure is responsible for the movement of air into and out of the lungs. Intra-alveolar pressure pressure within alveoli, changes during phases of breathing Explain how surfactant prevents the collapse of the lungs. Describe the partial pressure gradients for O2 and CO2. in external respiration and internal respiration Contrast fetal hemoglobin with adult hemoglobin. Adult o Alpha-beta Fetal o Alpha-gamma Explain how O2 and CO2 are transported in the blood. Oxygen o 1.5% dissolved in plasma o 98.5% bound to Fe of hemoglobin (Hb) Carbon Dioxide ▪ Three forms 7-10% dissolved in plasma 20% bound to hemoglobin Binds specific amino acids on hemoglobin to form carbaminohemoglobin 70% transported as bicarbonate ions (HCO3–) in plasma Explain the O2/CO2 exchange in the lungs and at the tissues. Describe the respiratory areas of the brainstem and how they produce a rhythmic pattern of ventilation. Pulmonary ventilation o Can be under voluntary control o When sleep or focused on other tasks = regulated involuntary Respiratory rate Neural controls involve reticular formation of medulla and pons Medullary respiratory centers o Ventral respiratory group ▪ produces the normal, involuntary rhythm of breathing called eupnea o Dorsal respiratory group ▪ modifies the respiratory rhythm. o Excite inspiratory muscles via phrenic(diaphragm) o intercostal nerves (external intercostals) Explain how blood pH, CO2 and O2 levels affect ventilation. Know is Henry’s Law, Bohr Effect, Dalton’s law  Henry’s Law o Concentration of a gas in a liquid is determined by its partial pressure and its solubility coefficient at a given temperature. o Each gas will dissolve in the liquid in proportion to its solubility (ability to dissolve) and partial pressure ▪ solubility decreases inversely with temperature ▪ greater partial pressure = more soluble ▪ At equilibrium partial pressures in the two phases will be equal Bohr Effect o effect of pH on oxygen-hemoglobin dissociation curve ▪ pH of blood declines = amount of oxygen bound to hemoglobin at any partial oxygen declines Dalton’s Law of partial pressures o Mixture of gases = sum of pressures exerted by each gas Relationship of pressure to volume Discuss the Hering‒Breuer reflex and its importance. LIMITS the depth of inspiration and prevents overinflation of the lungs Explain how the cerebral cortex and limbic system can affect ventilation. Hypothalamic controls o Modifies rate and depth of respiration through limbic system o Ex: breath holding in anger or gasping with pain Cortical controls o direct signals from cerebral motor cortex o bypass medullary controls o Ex: voluntary breath holding Know the carbon dioxide/carbonic acid/bicarbonate equation... what does do? Regulates Blood pH o The equation acts as a buffer system that helps maintain blood pH within a narrow range (around 7.35–7.45). CO₂ Control o Increased CO₂ ▪ shifts the reaction right, producing more H⁺, which lowers pH (more acidic) ▪ Ex: during exercise o Decreased CO₂ ▪ shifts the reaction left, using up H⁺ and raising pH (more basic).  ▪ Ex: Hyperventilation Two different circulations associated with the lungs: pulmonary and bronchial Fetal respiration help tone muscles in preparation for breathing once born Birth o Through birth canal thoracic cavity compressed, expelling fluid from lungs o Preterm birth frequently results in severe respiratory distress o Prior to 26 weeks, sufficient pulmonary surfactant NOT produced Chemicals monitored for respiration Chapter 27: Fluids, Electrolytes and Acid/Base List the dominant cations and anions in the major fluid compartments. Cations o Sodium (Na+) o Potassium(K+) Anions o Bicarbonate (HPO4 ^-2) o Chloride Describe the causes of edema. Edema o Interstitial fluid accumulation o Causes ▪ Hypernatremia High plasma sodium levels Leads to confusion, seizures, and coma ▪ Glucocorticoids (cortisol = stress) Increase Na+ (Sodium reabsorption Discuss what body fluid osmolality is and how it effects water movement Body fluid osmolarity o Change in the concentration leads to change in osmolarity leads to water flow o ECF osmolality -> water leaves cell, more salt o ECF osmolality -> water enters cell, less salt o Maintained around 280-300mOsm = Healthy o Rise in osmolality ▪ Stimulates thirst ▪ Cause ADH release o Decrease in osmolality ▪ Inhibits thirst ▪ Cause ADH inhibition Understand fluid intake vs fluid loss Fluid intake o Intake must equal output o Food and Beverages (90%) o Cellular respiration (10%) (Metabolic water) o About 2.5L-3.0L of water per day  o Output: ▪ Kidney -Most fluid as urine ▪ Evaporation- 1/3 lost through the skin and respiratory passageways ▪ Feces- 4% loss from the digestive system tract Fluid loss o Obligatory water losses ▪ Why we CANNOT live without water very long ▪ Insensible water loss Lungs, skin, and feces ▪ Sensible water loss Urine to excrete wastes Minimum daily loss of 500ml Volume of urine also depend on o Fluid intake o Diet o Water loss Demonstrate an understanding ion homeostasis. Sodium o most abundant cation outside the cell o Major contributor to osmotic pressure o Changes affect ▪ plasma volume ▪ blood pressure ▪ ECF/IF volumes ▪ Nervous and muscle function o water balance linked to blood pressure/volume control mechanisms o Changes in pressure/volume trigger neural and hormonal controls ▪ Renin-angiotensin-aldosterone mechanism ▪ Atrial natriuretic peptide (ANP) ▪ Other hormones o Regulation o Aldosterone plays biggest role o High Aldosterone = Sodium actively reabsorbed o Low aldosterone = Sodium not absorbed o Elevated K+ can also triggers aldosterone production o Water follows SALT o Renin-angiotensin-aldosterone mechanism ▪ Kidneys release renin ▪ Renin catalyzes production of angiotensin II which targets adrenal gland ▪ Adrenal cortex releases aldosterone which targets kidney (DCF) ▪ Increased Na reabsorption and K secretion o Other hormones o Estrogens ▪ increase NaCl reabsorption ▪ LEADS to water retention o Progesterone ▪ decreases Na+ reabsorption ▪ Promotes salt/water LOSS o Glucocorticoids ▪ Cortisol =stress  ▪ Increase Na+ reabsorption and promote edema Calcium + Phosphate o Function ▪ Important for exocytosis, including neurotransmitters ▪ Needed for muscle contraction ▪ Regulates action potential in cardiac muscle o Regulation ▪ Regulated by the kidneys, digestive tract, and bones. ▪ Balance between deposition and reabsorption from bone. ▪ Balance between absorption from intestines and excretion by kidneys Know the role of: the renin-angiotensin-aldosterone system, atrial natriuretic hormone and antidiuretic hormone (ADH). ADH o Made by hypothalamus o Released by posterior pituitary gland o Release proportional to WATER REASORBTION o Decreased ADH = DILUTED URINE o Increased ADH = CONCENTRATED URINE o Osmoreceptors sense solute o Decreased blood pressure ▪ Triggers ADH release ▪ Caused by large changes quickly Intense sweating Vomiting Diarrhea Severe blood loss Renin-angiotensin-aldosterone o INCREASES blood pressure and fluid retention through RENIN, ANGIOTENSIN II, and ALDOSTERONE. o Kidneys release RENIN o Renin catalyzes (cause a reaction) of ANGIOTENSIN II o ANGIOTENSIN = targets adrenal gland o ADRENAL CORTEX RELEASES ALDOSTERONE o Increased Na (Sodium) reabsorption o Increased K secretion atrial natriuretic hormone o DECREASES blood pressure + fluid volume through natriuresis and vasodilation o Atrial cells RESPOND to stretch by increased blood pressure o Targets ▪ Kidney ▪ Hypothalamus ▪ Adrenal gland o Works to decrease blood pressure/volume o Inhibits ADH, renin, and aldosterone production  o Loss of Na (Sodium) and water o Promotes vasodilation Explain the actions of the different types of buffer systems of the body. Chemical Buffer Systems o System that acts to resist drastic pH changes o Mechanisms for regulation of concentration o Work immediately o Three major chemical buffering system: ▪ Bicarbonate ▪ Phosphate ▪ Protein o Psychological buffer systems ▪ Respiratory system Short term Rapid response through breathing ▪ Renal system Long term Slower response Taking hours to days Bicarbonate o Buffers ICF and ECF o Primary Buffer o pH decreases = HCOɜ-(BICARBONATE) ties up H+ and forms H2CO3(Carbonic Acid) o pH INcreases = H2CO3(Carbonic Acid) dissociate and DONATE H+ to form water o Bicarbonate [HCOɜ-] closely regulated by KIDNEYS o Carbonic Acid [H2CO3] supply is ALMOST limitless Phosphate o Second line of defense o Action nearly identical to bicarbonate buffer o Effective mostly in urine Protein o Intracellular proteins are plentiful o Amphoteric ▪ Function as weak acid and weak base ▪ pH rises, carboxyl groups release H+ ▪ pH falls, NH group bind H+ ▪ Hemoglobin functions as an Intracellular buffer Explain the causes and effects of acid-base imbalances.  Respiratory system causes acid-base imbalances o Hypoventilation causes RESPIRATORY ACIDOSIS o Hyperventilation causes RESPIRATORY ALKALOSIS Respiratory acidosis/alkalosis o Failure of respiratory system to perform pH- balancing role o Most important indicator is Pco2(partial pressure of Carbon dioxide) Metabolic acidosis/ alkalosis o Failure of kidney to maintain pH o Abnormal HCO3- levels Understand how the hypothalamic thirst center function Osmoreceptors – detect INCREASES of 1-2% Baroreceptors sense – DECREASED of blood volume/pressure Signal sent to HYPOTHALAMIC THIRST CENTERS in the medulla oblongata Resulting in dry mouth (reduced saliva) Define hyponatremia, hypernatremia, hypokalemia, hyperkalemia, hyperphosphatemia, hypophosphatemia. Hyponatremia o Low plasma sodium levels o Can lead to confusion, seizures, coma Hypernatremia o High plasma sodium levels o Lead to pulmonary edema muscle convulsions Hypokalemia o Abnormally LOW levels of POTASSIUM in extracellular fluid Hyperkalemia o Abnormally HIGH levels of POTASSIUM in extracellular fluid Hyperphosphatemia o High phosphate levels o Due to RENAL FAILURE, CHEMOTHERAPY, HYPERPARATHYROIDISM (secondary to elevated plasma calcium levels) Hypophosphatemia o Low phosphate levels o Due to reduced absorption from intestine from VITAMIN D DEFICIENCY or ALCHOL ABUSE Know difference between metabolic acidosis/alkalosis and respiratory acidosis/alkalosis and compensation. Respiratory acidosis/alkalosis o Failure of respiratory system to perform pH- balancing role o Most important indicator is Pco2(partial pressure of Carbon dioxide) Metabolic acidosis/ alkalosis o Failure of kidney to maintain pH o Abnormal HCO3- levels Respiratory compensation o Lungs compensate for metabolic pH problems o Metabolic acidosis ▪ INCREASING rate/depth of breathing o Metabolic alkalosis ▪ DECREASING breathing, CO2 accumulates  Renal compensation o Kidneys compensate for pH problems cause by lungs o Respiratory acidosis ▪ Kidneys compensate for HCO3-, create new HCO3- and secrete more H+ o Respiratory acidosis ▪ Kidney Reabsorb more HCO3-(Bicarbonate) Create new HCO3-(Bicarbonate) Secrete more H+ o Respiratory alkalosis Kidney excrete more HCO3-(Bicarbonate) Know the carbon dioxide/carbonic acid/bicarbonate equation. Explain the effect an acidic environment has on oxygen transport