Ethan Johnson , Period 2 Respiratory System
Major Functions
Obtains oxygen from the atmosphere, and removes carbon dioxide from the body cells
Consists of tubes that warm and moisturize incoming air while also filtering it.
Also remove particles from incoming air , regulates temperature and water content in air , provides vocal sounds
Upper respiratory tract and functions
Nose - Entrance and exit for air , have coarse hair to remove particles
Nasal cavity - Divided medially by nasal septum , Conchae support mucous membranes, and increase the surface area to warm, moisturize, and filter incoming air
Respiratory volumes and capacities
Sinuses - Air-filled spaces in the maxillary, frontal, ethmoid, and sphenoid bones , they reduce the weight of then skull and serve as resonant chambers of the voice
Pharynx - Common passageway for air and food from nasal and oral cavities , aids in pronouncing sounds for speech
Lower respiratory tract and functions
Larynx - Transports air in and out of the trachea , Helps keep particles from entering the trachea , houses the vocal cords
Trachea - Cylindrical tube that goes downward to the esophagus and into the thoracic cavity , Inner wall is lined up with ciliated mucous membrane with many goblet cells , those goblet cells product mucus that trap incoming particles
Bronchial tree - Consists of branched , mucous membrane-lined airways
Terminal bronchioles: branches off larger bronchioles, smallest bronchioles that conduct air
Respiratory bronchioles: branch off terminal bronchioles, contain alveoli, so can perform gas exchange
Lungs - cone-shaped organs of the respiratory system , Contain air passages, alveoli, blood vessels,
connective tissues, lymphatic vessels, and nerves
Layers of the Pleura
Double layered-serous membrane
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Visceral pleura: inner layer; attached to the surface of each lung
Parietal pleura: outer layer; lines the thoracic cavity
Serous fluid lubricates the pleural cavity between the 2 layers
Inspiration - Air moves from higher to lower pressure , When pressure inside the lungs decreases below atmospheric pressure, air flows in from the atmosphere, Diaphram and intercostal muscles expand during normal inspiration. Diaphram contracts and moves downwards, Due to surface tension between the 2 layers of the pleura, as
the thoracic cavity expands, the lungs expand with it
Expiration - Results from the passive process of elastic recoil of the muscle and lung tissues , The diaphragm and intercostal muscles relax during this time , The diaphragm then gets pushed upward ,As the lungs recoil, the pleura and chest wall are pulled inward
Differences and compaisons of expiration and inspiration
Tidal volume (TV) - volume of air that enters or leaves the lungs during one respiratory cycle
Inspiratory reserve volume (IRV) - volume of air that can be inhaled in addition to the tidal volume, during forced inspiration;
Expiratory reserve volume (ERV) - volume of air that can be exhaled during a maximal forced expiration, beyond the tidal volume;
Residual volume (RV): volume of air that remains in the lungs after a maximal expiration, cannot be measured with a
spirometer
Inspiratory capacity (IC) - is volume of air that can be inhaled after a normal, resting expiration;
Functional residual capacity (FRC) - is volume of air that remains in lungs after a resting expiration
Vital capacity (VC) - is maximum volume of air that can be exhaled after a maximal inspiration;
Total lung capacity (TLC) is total volume of air the lungs can hold, depends on gender , age and body size
Diseases
COPD - Chronic obsructive Pulmonary disorder
Tuberclosis - Bacterial infection in the respiratory system caused by myobacterium tuberclosis
Pneumonia - Bacterial or viral infection of lungs
Lung cancer - Uncontrolled cell growth and tumors in lungs
Seasonal flu - A viral infections with many variations