Respiratory system 1 Flashcards
What is the role of the respiratory system
To keep air warm, clean and moist. And in close proximity with blood for gas exchange
What are the main components of the respiratory tract
Nasal cavity (olfaction) Oral cavity Conducting region (nose to bronchioles) Respiratory region (alveoli)
What are most of the bodies organs lined with
Mucosa
What are the layers of the respiratory tract
Epithelia attached by basement membrane to the lamina propria then the submucosa below
What is the lamina propria made of
Connective tissue
Possibly glands or blood vessels
What epithelia is present in the different regions of the respiratory system
Changes along length of the tract to reflect function.
Conducting region: Respiratory epithelium
Mouth/throat: Stratified squamous (where food travels)
Site of gas exchange: Simple squamous
Olfaction: Olfactory mucosa
Describe respiratory epithelium
Pseudostratified ciliated columnar epithelium (with goblet cells)
(pseudostratified - all call touch basement membrane but gives off a look of layers)
Where is respiratory epithelium found
Nasal cavity, pat of the pharynx, larynx, trachea and bronchi
What is the point of goblet cells
Produce mucus that traps debris and moistens the air.
What is the point of ciliated cells
Patterned movement pushes mucus towards pharynx then swallowed and digested by stomach
What are the components of the Upper Respiratory Tract (URT)
Nose & Nasal cavity
Paranasal sinuses
Pharynx (Nasopharynx, Oropharynx, laryngopharynx)
What are the functions of the URT
Conducting passage - both air and food
Prepares air for gas exchange (warm, clean, moist)
Paranasal sinuses - resonating chambers for speech
Olfaction - smell receptors
Describe the components of the nose
Brige - 2 nasal bones
Cartilage - soft, flexible, maintain patent/unobstructed airway
Nostrils - external/anterior nares
Vestibule lined skin - sebaceous and sweat glands, hair follicles - Vibrissae (filter inhaled air
What are the bones of the nasal complex
Nasal septum and midline (separates into sides) - anterior cartilage. - Posterior bone
Roof of cavity formed by ethmoid and sphenoid bones
Floor cavity formed by hard and soft palates.
Conchae on lateral walls
Describe the conchae
3 projections (superior, middle and inferior)
Covered by respiratory epithelium
Swirl inspired air, particles stick to mucosa
What is the purpose of the conchae
Turbines - ore time for warming and humidifying of air, olfactory detection
Describe nasal epithelium
Nasal cavity - mostly respiratory epithelium
Olfactory mucosa - area on roof of nasal cavity - contains smell receptors (olfactory nerve fibres)
Describe the nasal mucosa
Epithelium on lamina propria
network (plexus) of thin walled veins
What does the nasal mucosa do
Warm incoming air (radiation) - when air temp drops vascular plexus dilates (greater heat transfer)
Describe the paranasal sinuses
Sinus - cavity within a bone. Paranasal - surrounding the nose
Within frontal, sphenoid, ethmoid and maxillary bones
Lined with respiratory mucosa
Drains into pharynx
What are the functions of the paranasal sinuses
Lighten skull
Increase surface area (to clean air etc.)
Sound resonance (amplifies voice)
Infected mucus can block drainage = blocked sinuses
Describe the pharynx
Muscular funnel shaped tube - used by respiratory and digestive system. (throat)
Three regions: Nasopharynx, Oropharynx, Laryngopharynx.
Where is the Nasopharynx located and lined with
Air passage only - respiratory mucosa
Posterior to nasal cavity - from posterior nares to soft plate
Describe the Nasopharynx
Soft plate and uvula block during swallowing to prevent food entering nasal cavity
Auditory tubes drain here from middle ear
Pharyngeal tonsils (adenoids) posterior wall
Describe the Oropharynx
Air and food - Stratified squamous - protection against abrasions
Palatine tonsils
Lingual tonsils
Where is the Oropharynx located
Posterior to oral cavity
From soft platelets to hyoid bone
Describe the Laryngopharynx
Air and food - Stratified squamous
Food has ‘right of way’ during swallowing
Where is the Laryngopharynx located
From hyoid bone to opening of larynx/beginning of oesophagus
Ends at level where respiratory and digestive tracts diverge
