Exam 2 Flashcards
Describe the functions of the lymphatic system
a. Lymph vessels transport dietary lipids
i. Lymphatic capillaries called lacteals absorb lipids in intestine
b. Lymphatic organs aid in the production and maturation of lymphocytes
c. Lymphatic system generates immune response against antigens
i. Lymphocytes and macrophages monitor body for foreign substances
1. Some of the cells produce antibody proteins that bind the pathogen
2. Other lymphatic cells attach the antigen directly
3. Other lymphatic cells become memory cells to quickly attack the antigen if it appears again
d. Provides the space for lymph fluid to flow
e. Lymph vessel network transports excess fluid back to the blood
Identify the organs of the lymphatic system, and the general functions of each organ, including lymph nodes, tonsils, spleen, thymus.
Lymph nodes: filter antigens from lymph and initiate an immune response
Tonsils: immune surveillance of inhaled and ingested substances
Spleen: initiates an immune response when antigens are found in blood, serves as a reservoir for erythrocytes and platelets, phagocytizes old, defective erythrocytes and platelets and bacteria/other foreign materials
Thymus: site of T-lymphocytes differentiation and maturation
Describe the pathway of the lymphatic system from the capillary level to return of fluid to the venous system. Indicate the importance of the thoracic duct and the right lymphatic duct.
As it flows through the network, lymph is carried through progressively larger diameter vessels:
Lymphatic capillaries – lymphatic vessels – lymphatic trunks – lymphatic ducts
Afferent lymphatic vessels bring lymph to a lymph node
Efferent lymphatic vessels transport filtered lymph away from the lymph node
The right lymphatic duct returns lymph from the right side of the head and neck, right upper limb and right side of the thorax.
The thoracic duct collects lymph from most of the body (excluding right lymphatic duct drainage)
Explain how lymphatic vessels help maintain interstitial fluid balance.
Hydrostatic pressure: physical pressure of blood flowing through the vessels or of fluid in interstitial spaces; force exerted by the fluid pressing against a wall.
Osmotic pressure: movement of solutes (plasma or tissue fluid) through the plasma membrane in the presence of large proteins
The difference in protein concentrations between the blood and interstitial fluid is responsible for osmosis
i. Anchoring filaments linking endothelial cells to surrounding structures prevent vessel collapse
ii. Pressure of lymph inside vessel forces intercellular openings (“flaps”) of capillary wall to close with lymph inside
b. Lymph moves through vessels of larger and larger size
c. Net filtration pressure (NFP)
NFP = Net hydrostatic pressure (NHP) minus net osmotic pressure (NCOP)
i. Arterial end of capillary
1. Net hydrostatic pressure > Net colloid osmotic pressure
a. Net pressure out
b. Filtration
ii. Venous end of capillary
1. Net colloid osmotic pressure (COP) > net hydrostatic pressure (HP)
a. Net pressure in
b. Reabsorption
Describe the various infectious agents that impact the human body
a. Viral: Pieces of DNA or RNA in protein shell, Not cells- much smaller
Obligate intracellular parasites: Must enter cell to reproduce, Direct infected cell to make copies of nucleic acid and capsid, Virus or immune response may kill host cell
b. Bacterial: Single celled prokaryotes: Small cell with both a membrane and cell wall, Can be harmless or virulent
c. Fungal: Eukaryotic cells with membrane and cell wall
d. Prions: Fragments of infectious proteins, Neither cells nor viruses, Cause disease in nervous tissue
e. Protozoans: Eukaryotic cells without cell wall, Intracellular and extracellular parasites
f. Multicellular parasites: Non-microscopic, Take nourishment from host they live in
identify the specific white blood cells involved in immune function
Neutrophils (most abundant leukocytes): phagocytize pathogens
Eosinophils: phagocytize antigen-antibody complexes, release chemical mediators to destroy parasitic worms
Basophils: release histamine causing vasodilation
Lymphocytes: coordinate immune cell activity, attack pathogens and abnormal and infected cells, produce antibodies (active immunity)
Monocytes: become macrophages
Compare innate immune responses to adaptive immune responses
Innate
- provides fast general defense
- recognize some general molecular property marking the invader as foreign and protect the body as the first line of defense
- responds nonspecifically to range of harmful substances
- most immune cells: macrophages, NK cells
- chemicals: interferon, complement
- physiological responses: inflammation, fever
- cell mediated
- toll-like receptors
- complement system
- opsonization
- proinflammatory chemical secreting cells
- basophils, mast cells which promote inflammation
- phagocytes: neutrophils, macrophages, dendritic cells
- humoral: interferons, complement proteins, opsonins
- first line defense is skin, mucosal membrane and secretion
- second line of defense involves internal processes
Adaptive
- provided by lymphocytes that are activated to replicate and respond when stimulated by specific antigen
- there is a diversity of lymphocytes and receptors
- there is self-tolerance; lack of reactivity against an animals’ own molecules
- B and T cells proliferate after activation
- Immunological memory
- T lymphocytes: cell-mediated
- B lymphocytes: humoral (antibody production)
- specific responsive elements to certain pathogens
- differentiated cells: effector and memory
Distinguish how toll-like receptors, interferon and complement proteins function in immune protection.
- Toll like receptors: play critical roles as pattern recognition receptors, mainly expressed in antigen presenting cells (macrophages/dendritic), signaling activates antigen presenting cells to provoke innate immune response and to establish adaptive immunity.
- Complement system: kills pathogens and triggers immune response. Composed of family of plasma proteins that lyse foreign cells, especially bacteria. Involves membrane attack complex which causes perforation in cells it attacks.
- interferon: transiently inhibits multiplication of viruses in most cells, released from virus-infected cells, acts as “whistle-blower”
Contrast active acquired immunity to passive acquired immunity
- Active: antibodies developed in response to infection or developed in response to vaccination. Resistance built up as a result of body’s contact with microbes and their toxins or other antigenic components
- Passive: antibodies received from mother or from medicine. Direct transfer of antibodies from one person to another, recipient receives pre-formed antibodies
Explain the various types of acquired immune cells, where they are formed and their physiological roles in immunity: T, B, and Helper T.
- T cells: formed in bone marrow, mature in thymus
- Cytotoxic: recognize antigen-MHC1 on infected cells
- mediates cell-mediated adaptive immunity - B cells: formed in bone marrow, mature in bone marrow
- have antibody plasma proteins and antigen binding sites - Helper T: recognize antigen-MHC2 on antigen presenting cell
Describe the five different types of antibodies, and generally how they work
- IgA: class of antibodies secreted by cells lining the GI, respiratory, and genitourinary tracts. Accounts for 10-15% of antibodies.
- IgD: A class of antibodies whose function is unknown
- IgE: the class of antibodies that mediates immediate hypersensitivity to pollen, spores, animal dander. four in lungs, skin, mucus membranes
- IgG: the most abundant class of plasma antibodies (75%): found in all body fluids. target viruses and bacteria. only antibodies that can cross the placenta.
- IgM: i. Largest class of antibodies, 5-10%. Found in blood and lymph fluid. Produced first in all immune responses. Along with IgG, provide the bulk of specific humoral immunity against bacteria and viruses.
Identify the physiological factors that can alter the body’s immune system
- Age: size of thymus changes (shrinks with age)
- protein-calorie malnutrition
- preexisting disease
- most exercise and physical conditioning
- stress and person’s state of mind
- sleep deprivation
Describe the structural anatomy of the respiratory system
- Conducting division: passages for air flow (without gas exchange); nose, pharynx, larynx, trachea, bronchus, bronchiole, terminal bronchioles
- Respiratory division: gas exchange areas; respiratory bronchioles and alveoli
Differentiate between the upper and lower respiratory tracts
- Upper: nose, pharynx, larynx
- Lower: trachea, bronchi, lungs, branches within lungs
Compare and contrast external and internal respiration
Internal respiration: at the level of the tissues
External respiration: at the lungs
Explain the anatomy and functions of the nasal cavity.
Anatomy:
- hard palate: floor of nasal cavity
- nasal septum: divides cavity. Anterior cartilage; posterior vomer and perpendicular plate of ethmoid
- nasal conchae
Functions
- passageway for air
- cleans, humidifies, warms air
-smell
- along with paranasal sinuses, are responding chambers for speech
Explain the anatomy and functions of the pharynx
- Nasopharynx
- pseudostratified columnar epithelium with goblet cells
- openings of eustachian (auditory) tubes
- floor is soft palate, uvula is posterior extension of the soft palate - Oropharynx
- shared with digestive system
- lined with moist stratified squamous epithelium - Laryngopharynx
- epiglottis to esophagus
- lined with moist stratified squamous epithelium
Function:
Serves as common opening for respiratory and digestive systems
Explain the anatomy and functions of the larynx
- Large cartilaginous structure in throat
- thyroid: largest, “adam’s apple”
- cricoid: most inferior, base of larynx
- epiglottis: attached to the thyroid and has a flap near base of tongue, elastic rather than hyaline cartilage - paired
- vestibular folds or false vocal folds
- true vocal cords or vocal folds: sound production - glottis
- opening between folds
Describe the cellular organization of the trachea and its importance
a. Membranous tube of dense regular connective tissue and smooth muscle
b. Inner lining: pseudostratified ciliated columnar epithelium with goblet cells
i. Mucus traps debris cilia push it superiorly toward larynx and pharynx
Identify how the trachea branches as it descends into the lungs
a. Trachea divides into two primary bronchi
b. Primary bronchi divide into secondary bronchi, then divide into tertiary bronchi
c. Tertiary bronchi further subdivide into bronchioles then finally into terminal bronchioles.
Define the respiratory zone of the lungs
a. This is composed of the respiratory bronchiole, alveolar duct, alveoli
b. Site for gas exchange
c. Respiratory bronchioles branch from terminal bronchioles
d. Respiratory bronchioles have very few alveoli
e. Alveolar sacs have multiple alveoli at their terminus
f. No cilia, but debris removed by macrophages
Explain the functional organization of the lungs: lobes and fissures
a. Base sits on the diaphragm, apex at the top, hilum on medial surface where bronchi and blood vessels enter the lung
b. Right lung: three lobes. Lobes separated by fissures.
c. Left lung: two lobes, and an indentation called the cardiac notch
Describe the respiratory membrane structures and the cell types that are responsible for respiration
- thin layer of fluid lining the alveolus (surfactant)
- alveolar epithelium (simple squamous epithelium)
- basement membrane of alveolar epithelium
- basement membrane of capillary endothelium
- capillary endothelium composed of simple squamous epithelium
Cell types - Type 1 pneumocytes. thin squamous epithelial cells, form 90% of surface of alveolus. gas exchange
- Type 2 pneumocytes. surfactant producers
- macrophage cells: immune cells in alveoli
Identify the function of the pleura
Allows for lung inflation by having intrapleural pressure lower than intrapulmonary pressure and lung deflation when intrapleural pressure is higher than intrapulmonary pressure
Compare and contrast the muscles of inspiration and expiration
a. Muscles of inspiration
Diaphragm (passive)
External intercostals (active)
Pectoralis minor (accessory)
Sternocleidomastoid (acc)
b. Muscles of expiration
Diaphragm (relaxing)
Internal intercostals (active)
Abdominals (accessory, active)
