✅Lungs And Repiration System Flashcards
What are the functions of the respiratory system?
- Provides extensive gas exchange surface area between air and circulating blood
- Moves air to and from exchange surfaces of lungs
- Protects respiratory surfaces from outside environment
- Produces sounds
- Participates in olfactory sense
How does the respiratory system Moves the air to and from the exchange surface?
• Via nose, mouth, pharynx, larynx, trachea, bronchi to the lungs
• Moistens, warms and filters the air
How does the respiratory system Provide an extensive surface for gas exchange?
Alveoli or air sacs
How does the respiratory system Protect the respiratory surfaces at each stage from: dehydration, temperature changes, pathogens etc.
• Via vibrassae (nose hairs), mucosal membranes, surfactants and macrophages
• Reflexes such as coughing and sneezing
What does the respiratory tract consist of?
A conducting portion and a respiratory portion
Where is the conducting portion?
From nasal cavity to terminal bronchioles
Where is the respiratory portion?
The respiratory bronchioles and alveoli in the lungs
What are the components of the respiratory system?
The upper respiratory tract (above the larynx) and the lower respiratory tract (larynx and below).
What is the function of the respiratory system?
Exchange of carbon dioxide and oxygen is the primary function.
What is involved in the upper respiratory tract?
the nose, nasal cavity, paranasal sinuses and pharynx
What are the functions of the upper respiratory tract
• To purify, warm and humidify ambient air before it moves into the lower respiratory tract.
• Acts as a conduction pathway for the air to move into the lower respiratory tract.
How does air enter the respiratory system?
Through nostrils or external nares
Into nasal vestibule
What happens in the nasal cavity?
– The nasal septum
• Divides nasal cavity into left and right
– Superior portion of nasal cavity is the olfactory region
• Provides sense of smell
– Mucous secretions from paranasal sinus and tears
• Clean and moisten the nasal cavity
Describe Air flow in upper respiratory tract
From the vestibule to internal nares
• Through superior, middle, and inferior
meatuses
• Meatuses are constricted passageways that produce air turbulence
– Warm & humidify incoming air – Trap particless
Describe the hard palate
– Forms floor of nasal cavity
– Separates nasal and oral cavities
Describe the soft palate
– Extends posterior to hard palate
– Divides superior nasopharynx from lower pharynx
What does the respiratory mucosa consist of?
- An epithelial layer
- An areolar layer called the lamina
What foes respiratory mucosa do?
Line the conducting portion of respiratory system
What is the lamina propria?
Underlying layer of areolar tissue that supports the respiratory epithelium
What does the lamina propria do in the upper respiratory system, trachea and bronchi?
Contains mucous glands that secrete onto epithelial surface
What does the lamina propria do In the conducting portion of lower respiratory system
Contains smooth muscle cells that encircle lumen of bronchioles
What does the cilia from the epithelial cells form?
A dense layer
What does the movement of the cilia in the epithelial do?
propels mucus across the epithelial surface.
Describe the structure of the respiratory epithelium
– Pseudostratified ciliated columnar epithelium with numerous mucous cells
• Nasal cavity and superior portion of the pharynx
– Stratified squamous epithelium
• Inferior portions of the pharynx
– Pseudostratified ciliated columnar epithelium
• Superior portion of the lower respiratory system
– Cuboidal epithelium with scattered cilia
• Smaller bronchioles
What does the respiratory defence system consist of?
a series of filtration mechanisms
What does the respiratory defence system do?
It removes particles and pathogens
What are the components of the respiratory defence system
– Mucous cells and mucous glands
• Produce mucus that bathes exposed surfaces
– Cilia
• Sweep debris trapped in mucus toward the pharynx
(mucus escalator)
– Filtration in nasal cavity removes large particles
– Alveolar macrophages engulf small particles that reach lungs
What is the pharynx
A chamber shared by the digestive and respiratory systems
Where is the pharynx?
Extends from internal nares to entrances to larynx and oesophagus
What are the three parts of the pharynx
• The nasopharynx
• The oropharynx
• The laryngopharynx
Describe the nasopharynx
– Superior portion of pharynx
– Contains pharyngeal tonsils and openings to left and right auditory tubes
Describe the oropharynx
Middle portion of pharynx
Communicates with oral cavity
Describe the laryngopharynx
– Inferior portion of pharynx
– Extends from hyoid bone to entrance of larynx and esophagus
What is included in the lower respiratory tract?
Includes the larynx (voice box), trachea (windpipe), lungs, bronchi, bronchioles & alveoli