Chapter 22 Respiratory System Flashcards
pulmonary ventilation
-movement of air into and out of the lungs
external respiration
-O2 and CO2 exchange between the lungs and the blood
transport
-O2 and CO2 in the blood
internal respiration
-O2 and CO2 exchange between systemic blood vessels and tissues
anatomy of respiratory system
- nose
- nasal cavity
- pharynx
- larynx
- trachea
- bronchi
- lungs
- alveoli
the nose
- provides an airway for respiration
- moistens and warms the entering air
- filters and cleans inspired air
- serves as a resonating chamber for speech
- houses olfactory receptors (humans- 5 million scent receptors, bloodhounds have 300 million)
nasal cavity
- filter, heat, and moisten air
- vestibule- nasal cavity superior to the nostrils -> superior, middle, and inferior nasal conchae
- olfactory mucosa- smell receptors
- respiratory mucosa:
- goblet cells- contain lysozyme and defensins
- cilia- moves contaminated mucus
- warms inspired air
pharynx (throat): nasopharynx
- air passage
- uvula prevents food from entering cavity
- Eustachian tube
pharynx (throat): oropharynx
-pseudostratified columnar protects against friction and chemical trauma
pharynx (throat): laryngopharynx
-lies posterior to epilottis
larynx (voice box)
- attaches to the hyoid bone and opens into the laryngopharynx
- vocal ligaments and vestibular folds
- provides a patent airway
- routes air and food into proper channels
- voice production
- 9 cartilages of the larynx:
- thyroid cartilage (adams apple)
- ring shaped cricoid cartilage
- 3 paired cartilages
- epiglottis
vocal ligaments of larynx
-true vocal cords
vestibular folds of the larynx
- false vocal cords
- outermost folds
vocal cord surgery
-use of laser to stop bleeding and remove polyp
speech
-intermittent release of expired air while opening and closing the glottis
pitch
- determined by the length and tension of the vocal cords
- faster vibration- higher pitch (boys in puberty)
loudness
-depends upon the force of air
sound
-shaped into language by muscles of the pharynx, tongue, soft palate, and lips
larynx
- vocal folds may act as a sphincter to prevent air passage
- ex. valsava’s maneuver:
- glottis closes to prevent exhalation
- abdominal muscles contract
- intra-abdominal pressure rises
- helps to empty the rectum or stabilize the trunk during heavy lifting
trachea
- windpipe
- from the larynx to primary bronchioles
- wall composed of 3 layers:
- mucosa
- submucosa
- adventitia- outermost layer
conducting zone structures
- trachea -> right and left main (primary bronchi
- main bronchus enters the hilum of one lung
- each main bronchus branches into lobar (secondary) bronchi (3 right, 2 left)
- each lobar bronchus supplies one lobe
- lobar (secondary bronchus ->
- segmental (tertiary) bronchus ->
- bronchioles ->
- terminal bronchioles are the smallest, less than .5 mm diameter
left lung
- smaller due to heart
- right bronchus more vertical
respiratory zone
-respiratory bronchioles, alveolar ducts, alveolar sacs (clusters of alveoli)
alveoli features
- surrounded by fine elastic fibers
- open alveolar pores- equalizes air pressure throughout lung
- house alveolar macrophages- keeps surfaces sterile
smoking
- tobacco
- nicotine- stimulates increased HR
- carbon monoxide- blocks O2 transport in HB
- tar- cancer causing
- smoking paralyzes cilia
- without cilia inhaled particles cling to wall or enter lung
lungs
- 2 lungs
- left has 2 lobes
- right has 3 lobes
- apex- superior tip just under clavicle (top)
- base- concave inferior portion above diaphragm
- hilum- vessels
occasionally food or liquids will go down the wrong pipe, initiating a cough reflex. Which structural barrier has been breached in this happens
- laryngopharynx
- uvula
- epiglottis*
- glottis
epiglottis
-elastic cartilage- covers the laryngeal inlet during swallowing
glottis
-opening between the vocal cords
the respiratory membrane is composed of ____
- the alveolar sacs and pulmonary arteries
- the alveolar membrane, the capillary wall, and their fused basement membrane*
- the alveolar macrophages and elastic fibers
- the cells found between the alveolar pores
men tend to have deeper voices than women because their vocal cords ______
- have a wider opening
- art shorter and narrower
- have a narrower opening
- are longer and thicker*
blood supply
- pulmonary circulation- low pressure, high volume
- pulmonary AA- blood from heart to be oxygenated
- pulmonary VV- freshly oxygenated blood
- bronchial circulation- oxygenated blood to lung -> tissue
pleurae
- thin, double layered serosa
- parietal pleura- thoracic wall
- visceral pleura- on lung tissue
- pleural space- pleural fluid for lubrication
- allows friction free movement during breathing
pressure relationship in the thoracic cavity
- atmospheric pressure (Patm)- pressure exerted by the air surronding the body
- 760 mm Hg at sea level
- respiratory pressure: negative respiratory pressure is less than Patm
- positive respiratory pressure is greater than Patm
- zero respiratory pressure = Patm
intrapulmonary pressure
- intrapulmonary (intra-alveolar) pressure (Ppul)- pressure in the alveoli
- always eventually equalizes with Patm
- intrapleural pressure (Pip): pressure in the pleural cavity
- always a negative pressure (
pressure relationships
- if Pip (intrapleural)=Ppul (intralveolar) the lungs collapse -> pneumothorax
- Ppul - Pip = transpulmonary pressure
- keeps the airways open
- the greater the transpulmonary pressure, the larger the lungs
pulmonary vetilation
- inspiration and expiration
- mechanical processes that depend on volume changes in the thoracic cavity
- volume changes -> pressure changes
- pressure changes -> gases flow to equalize pressure
boyles law
- the relationship between the pressure and volume of a gas
- pressure (P) varies inversely with volume (V)
- P1V1 = P2V2