Chapter 22 Flashcards
respiratory system
supply the body with oxygen and dispose of carbon dioxide
processes of respiratory system
- pulmonary ventilation (breathing
- movement of air in and out of the lungs
- external respiration
- gas exchange between blood and air
- transportation of respiratory gases
- oxygen and carbon dioxide are transported between the lungs and the cells of the body, accomplished by the cardiovascular system
- internal respiration
- gas exchange between blood and tissue cells
functional anatomy of the respiratory system (organs)
nose, nasal cavity, paranasal sinuses pharynx larynx trachea bronchi and their smaller branches lungs (aveoli)
respiratory zones
conducting zone:
-the respiratory passages that carry air to the sites of gas exchange
respiratory zone:
-the actual site of gas exchange in the lungs
nose
functions:
-provides an airway for respiration
-moistens and warms entering air
-filters air to rid it of foreign particles
-serves as a resonance chamber for speech
-contains the olfactory (smell) receptors
divided into the external nose and the internal nasal cavity
nasal cavity
- air enter through the external nares (nostrils)
- the cavity is divided by the nasal septum
vestibule
the part of the nasal cavity that lies just superior to the nostrils
-lined with skin containing sebaceous and sweat glands and numerous hair follicles
mucous membranes
olfactory mucosa: (receptors for smell)
respiratory mucosa: (lines most of the nasal cavity)
nasal conchae
superior and middle (ethmoid bone) and inferior
-cause turbulence, which increases the contact between the air and the mucosa (so that particles can be trapped)
paranasal sinuses
ring of air-filled cavities surrounding the nasal cavity
- located in the frontal, ethmoid, sphenoid, and maxillary bones
- serve to warm and moisten inhaled air, trap foreign particles, and enhance voice resonance
pharynx
the throat
-funnel-shaped passageway that connects the nasal cavity, and mouth superiorly, to the larynx and esophagus inferiorly
divided into:
nasopharynx (superior)
oropharynx (middle)
laryngopharynx (inferior)larynx
the voice box -continuous with the trachea superiorly functions: 1. produces sound (voice) 2. provides an open airway 3. acts as a switching mechanism to route air and food into their correct passages
epiglottis
elastic cartilage flap that shuts off the larynx/trachea when swallowing
voice folds
(true vocal cords)
vibrate to produce sound when air passed through the larynx
trachea
(windpipe)
descends from the larynx and ends by dividing into the two primary bronchi in the mid thorax
composed of rings of hyaline cartilage and fibro elastic CT )WANT TRACHEA FLEXIBLE BUT ALSO KEPT FROM COLLAPSING)
tracheal wall
- mucous membrane (et and CT layers)
- submucosa (CT which contains mucus and serous cells)
- adventitia (CT with tracheal cartilages)
bronchi
right and left main (primary) bronchi
-branches off the trachea
lobar (secondary) bronchi
-branch off the main bronchi
-each supply one lung lobe
segmental (tertiary) bronchi
-branch off the lobar bronchi
fourth-order, fifth-order bronchi..lungs
located in the thoracic cavity, lateral to the mediastinum
-surrounded by pleura and the pleural cavity, which is filled with pleural fluid
anatomy of lungs
apex
base
hilus
-site where blood vessels, bronchi, lymph vessels, and nerves enter and exit the lung
lobes
-segments of the lungs
-left lung: has 2 lobes (upper and lower)
-right lungs: 3 lobes (upper, middle, and lower)
bronchioles
air tubes smaller than 1mm in diameter
- terminal bronchioles
- the smallest bronchioles < 0.5mm
respiratory zone
respiratory bronchioles
-branch from the terminal bronchioles
aveolar ducts
-extend from the respiratory bronchioles and lad into terminal clusters called aveolar sacs
aveolar sacs
-clusters of aveoli, which are the air-exchange chambers of the lungs
aveoli
-the lungs contain 300 million of them, which also provide a large amount of surface area
-surrounded by simple squamous
respiratory membrane
made up of the aveoli and their capillary beds
-where gas exchange occurs between aveoli and blood
anatomy of lungs pt2
bronchopulmonary segments
-make up the lobes
-each segment receives air from an individual segmental (tertiary) bronchus
-can be neatly removed in surgery and limits the spread of disease within the lung
lobules
-the smallest visible divisions of the lungs
blood supply
pulmonary arteries (heart to lungs) pulmonary capillary networks (beds) (form respiratory membrane) pulmonary veins (back from lungs to the atrium
pulmonary ventilation (inspiration)
- contraction of the diaphragm causes the height of the thoracic cavity to increase
- the external intercostals contract to raise the ribs
- the actions of both muscles enlarge the thoracic cavity, which increases the volume and decreases the pressure( therefore air is able to enter the lungs)
pulmonary ventilation (expiration)
the inspiratory muscles relax and the rib cage drops due to gravity
-the volume of both the thorax and lungs decreases, which increases the pressure within the lungs and forces air out
