Overview and URT Flashcards
What is the role of the respiratory system?
Respiratory system is a series of connected organs that allow you to conduct clean, warm and moist air - optimal condition of the air
Brought in close proximity with the blood for gas exchange (capillaries)
What does the respiratory system need to be effective?
Need a surface for gas exchange (blood and air brought close together - capillaries), need a path for air flow to reach gas exchange surface, ability to draw breath in and out (using bones and muscles), sound production and olfaction (smell - nose)
Main components of the respiratory system
Upper respiratory tract (URT), consists of nose, nasal cavity, pharynx and paranasal sinuses
Lower respiratory tract (LRT), consists of larynx, trachea, bronchus, bronchioles
Thoracic cavity, joints, respiratory muscles
Main zones and cavities of respiratory system
Respiratory zone - found inside lungs, constituted by the bronchioles and alveoli, site of gas exchange
Conducting zone - nose to bronchioles, where air is converted into optimal quality (warm, clean, moist)
Oral cavity - Mouth, passage for both air and food
Nasal cavity - Nose, primary passage way for air to be taken in, olfaction (smell)
Epithelia types in respiratory system
Respiratory epithelium (conducting region), stratified squamous (air and food travel), simple squamous (gas exchange) and olfactory mucosa (olfaction)
Tract is lined with mucosa, epithelium attached via basement membrane to lamina propria
Histological structures of respiratory system
Most body organs are lined with a mucosa (sheet of epithelial cells), it is attached via a basement membrane to the lamina propria (connective tissue, glands). Below it is a submucosal layer which contains more connective tissue and glands (mucus secreting)
What is the respiratory epithelium?
Respiratory epithelium is found in nasal cavity, part of pharynx, larynx, trachea and bronchi, make sure the air is clean
Goblet cells produce mucus (traps debris, moistens air)
Ciliated cells (patterned movement pushes mucus towards pharynx, swallowed and digested by stomach acid)
What is the other name for respiratory epithelium?
Pseudostratified ciliated columnar epithelium (with goblet cells)
Columnar - tall columns, stratified - stacked, pseudo - fake
Fake stack heavy tall cells which contain mucus
Components of URT
Nose and nasal cavity, paranasal sinuses and pharynx
Conducting passage, prepares air for respiratory membrane, resonating chambers for speech (paranasal sinuses) and sensory receptors (olfaction)
Components of the nose
Cartilages are soft, flexible and patent - unobstructed/open airway maintained through the nose
Nostrils are also known as external nares
Vestibule (passage) lined with skin - has sebaceous and sweat glands, hair follicles/vibrissae filter inhaled air (traps debris and stop them going any further into your tract)
Bones of nasal cavity
Anterior part of the nose is made of cartilage, posterior part is made of bone
Nasal cavity composed of different bones that form the roof of the cavity and the floor which is formed by hard and soft palates
Components of conchae
Conchae are found on lateral walls of the nasal cavity, it is covered by respiratory epithelium and the three projections (turbinates) swirl inspired air. Particles stick to mucosa and more time for warming and humidifying air plus olfactory detection
Components of nasal epithelium
Nasal epithelium is mostly composed of respiratory epithelium and is a specialised area of olfactory epithelium (found on roof of nasal cavity containing smell receptors)
Components of nasal mucosa
The vascular plexus is a network of thin blood vessels which help warm incoming air by giving off heat. When air temperature drops, plexus dilates resulting in greater heat transfer. Nose bleeds normally originate from here as vessels are very close to skin so easily damaged
Components of paranasal sinuses
Sinus - cavity within a bone, air filled
Paranasal - surrounding the nose
Lined with respiratory mucosa and drain into the pharynx
Functions to lighten skin, increase SA to clean, warm, moist air, sound resonance, can get blocked with infected mucosa (blocked sinuses)
