Chapter 22 Flashcards
what is the major function of the respiratory system
to supple the body with oxygen and to dispose of carbon dioxide
what are the four respiratory process
1) internal respiration: gas exchange between systemic blood and vessels and tissues
2) external respiration: gas exchange between the lungs and tissues
3) transport: transport of oxygen and carbon dioxide between the lungs and tissues
4) pulmonary ventilation: moving air into and out of the lungs
what are the two respiratory zones
1) conduction 2) respiratory
Describe the function of the conducting zone
provides rigid conduits for air to reach the sites of gas exchange. cleans, humidifies, and worms air.
what structures does the conduction zone include
nose, nasal cavity, pharynx, trachea
Describe the function of the respiratory zone
actual site or gas exchange,
what structures does the respiration zone include
bronchioles, alveolar ducts, alveoli
what is the function of respiratory muscles
to promote ventilation ex: diaphragm
Describe the structure of the nasal conchae
has three layers, superior, middle, inferior. Bony projections that extend into nasal cavity from lateral projections
Describe the strutter of the nasal meatuses
has three layers, superior, middle, inferior. groove like passages formed form the nasal conchae. (floor is formed form soft and hard plates)
what role does the internal nares (choanae) play
communication holes between internal nose and pharynx.
what part of the nose lines the s uperior nasal cavity and contains sell receptors
olfactory mucosa
what part of the nose lines the balance of the nasal cavity
respiratory mucosa
what is the function of seromucous nasal glands
to secrete mucus containing lysozymes and defences to help destroy bacteria
where are the paranasal sinus ducts located
mucosa lined air cavities where air is moistened and wormed
what is the structure of the pharynx
funnel shaped tube of skeletal muscle
what parts of the body does the pharynx connect to
1) nasal cavity and mouth superiorly
2) larynx and esophagus inferioryly
where does the pharynx extend from
the base of the skull to the 6th cervical vertebra
what are the three regions of the pharynx
1) nasopharynx 2) oropharynx 3) laryngopharynx
what is the function of the nasopharynx
strictly an air passageway. contains pharyngeal tonsil
what is the function of the oropharynx
servers as a common passage for both air and food
contains 2 paris of tonsils (platen and lingual)
what is the function of the laryngopharynx
serves as a common passage for food and air
what are the four main function of the pharynx
1) respiration (airway) 2) digestion (swallowing) 3) immunological role (tonsils) 4) sound (effects sound by acting as a resonance chamber)
what is the structure of the larynx
air passageway that connects pharynx with trachea, consists of nine pieces of cartilage (also known as voice box)
what are the three main types of cartilage in the larynx
1) thyroid 2) cricoid 3) epiglottis
what type of cartilage makes up the three main types of cartilage in the larynx
1) Thyroid: consists of hyaline cartilage (adams apple)
2) Cricoid: ringed hyaline cartilage (landmark for tracheostomy)
3) Epiglottis: leaf shaped elastic cartilage covers glottis when swallowing
in distending order list the structures of the larynx
epiglotis -> vestibular fold -> thryoid cartilage -> vocal fold -> cricoid cartilage
where does the trachea extend from
from larynx into mediastinum. 16-20 rings of incomplete cartilage. provides strong flexible support and protection
what are the four layers of the trachea
1) mucosa: made up of goblet cells and ciliated epithelium- lines lumen
2) submucosa: made up of connective tissue
3) hyaline cartilage: layer made up of c-shaped rings of hyaline cartilage
4) adventitia: outer most covering
what marks the the end of the trachea and the beginning of the right and left bronchi
the last tracheal cartilage (carina of trachea)
what does the secondary bronchi represent
bronchi subdivision,
how many secondary bronchi is there in the left and right lung
right lung = 3 (3 lobes)
left lung = 2 (2 lobes)
*one for each lobe
Secondary bronchi subdivides into ___, ___, ___,
tertiary bronchi, bronchioles, and terminal bronchioles
the tissue wall of the bronchi is similar to ?
the tracheal wall
as the the bronchi conducting tubes get smaller what structural changes occur
- cartilage changes from incomplete rings to plates and then disappears completely in bronchioles
- epithelium changes from ciliated columnar, to non-ciliated simple cuboidal
- amount of smooth muscle increases
what defines respiratory bronchioles
- defined by the presence of alveoli, begins as terminal bronchioles feed into respiratory bronchioles
- lead to alveolar ducts
list some of the structural components of respiratory bronchioles
- consist of cuboidal epithelium,
- have a complete layer of circular smooth muscle
- lack both cartilage support and mucus-producing cells
where do respiratory bronchioles lead to
they lead to alveolar ducts, then to terminal clusters of alveolar sacs, composed of alveoli
what accounts for most of the lungs volume
alveoli (~300 million)
-provide a lot of surface area for gas exchange
the air-blood barrier is composed of:
- alveolar and capillary walls
- their fused basal laminas
how do the two alveolar walls compare to one another
1) composed of simple squamous cells, surrounded by a flimsy basement membrane, allows for gas exchange through simple diffusion
2) composed of cuboidal cells that secrete “detergent-like” surfactant to coat alveolar and reduce surface tension
what are the three significant features about alveoli
1) contain pores (allow air pressure throughout lung to be equalized, connect adjacent alveoli)
2) surrounded by fine elastic fibers
3) contain macrophages that keep alveoli surface sterile
compare the right and left lung
right= is thicker, broader, and shorter than left lung, is separated into three lobes (superior, middle, inferior) by the horizontal fissure and oblique fissure. has three secondary bronchi left= separated into two lobes (superior, inferior) by the oblique fissure, has two secondary bronchi
the pleural cavity is filled with?
pleural fluid
what is the intrapulmonary pressure
- (Ppul) pressure within the alveoli
- always eventually equalizes itself with atmospheric P
what is the intrapleural pressure
- (Pin) pressure within the pleural cavity
- always less than intrapulmonary pressure and atmospheric pressure
what are the two forces that act to pull the lungs away from the thoracic wall, promoting lung collapse
- elasticity of lungs causes them to assume smallest possible size
- surface tension of alveolar fluid draws alveoli to their smallest possible size
what pressure keeps airways open in the lungs
transpulmonary pressure,
*transpulmonary pressure = Ppul-Pip
the inspiratory muscles include
diaphragm and external intercoastal
during inspiration what happens to intrapulmonary and intrapleural pressure
they both decrease
during expiration what happens to intrapulmonary and intrapleural pressure
they increase
define tidal volume
air that moves in and out of the lungs with each breath (~500ml)
define inspiratory reserve volume
air that can be inspired forcibly beyond the tidal volume (2100-3200) *inspiratory capacity (IC) = (IRV + TV)
expiratory reserve volume describes what
air that can be evacuated from the lungs after a tidal expiration (1000-1200ml)
what is the air left in the lungs afar strenuous expiration called
residual volume
define vital capacity (VC)
the total amount of exchangeable air (TV+IRV+ERV)
define total lung capacity
(TLC) sum of all lung volumes (~6000ml in males)
Define Boyle’s law
if capacity is reduced pressure goes up
Define Dalton’s law of partial pressures
the total gas pressure is equivalent to the sum of all the individual gas pressures
Define Henry’s Law
when a mixture of gases is in contact with a liquid, each gas will dissolve in the liquid in proportion to its partial pressure
- the greater the [gas] the faster it will go into solution form
- as liquid temp increases solubility goes down
compare the solubility of carbon dioxide, oxygen, and nitrogen
- carbon dioxide is the most soluble
- oxygen is 1/20th as soluble
- nitrogen is practically insoluble in plasma
oxygen has a steep partial pressure gradient
True, it allows oxygen partial pressures to rapidly reach equilibrium and thus blood can move three times as quickly,through the pulmonary capillary and still be adequately oxygenated
cardon dioxide has a lower partial pressure gradient than oxygen,
buttt it diffuses in equal amounts with oxygen
when is hemoglobin almost completely saturdayed
at a Po2 of 70mmHg
what happens if Po2 increases
produced only small increases in oxygen binding
how much oxygen is unloaded during one systemic circulation
20-25%
if oxygen levels in tissues drop what happens
- more oxygen dissociated from hemoglobin and is used by cells
- respiratory and cardiac output don’t increase
increases in H+, Po2, temp, and BPG, do what to hemoglobin saturation
decreases hemoglobins affinity for oxygen, enhance oxygen unloading form the blood
what happens as cells metabolize glucose
-carbon dioxide is realized in the blood causing: -increases in Pco2 and H+ concentration in capillary blood, decking pH (acidosis) which weakens the hemoglobin-oxygen bond (bohr effect)
