Respiratory System Chapter 13

Upper Respiratory Tract Lower Respiratory Tract

Nose Air enters the nose by passing through the external nares or nostrils The interior of the nose consists of the nasal cavity, divided by a midline nasal septum

Nose Mucus lines the interior of the respiratory tract Moistens the air Traps incoming bacteria and other debris Consists of water, salts, and glycoprotein (mucin) Cilia helps move the contaminated mucus towards the pharynx (throat) to be swallowed and digested by stomach juices Hair prevents some debris from entering the trachea

Nose Cold temperatures cause cilia to become sluggish, allowing mucus to accumulate in the nasal cavity and to dribble outward through the nostrils

Nose Conchae – the three uneven mucosa covered lobes that consist of the nasal cavity Superior

Nose The conchae traps and prevent inhaled particles from reaching the lungs Blood vessels in the nasal cavity warms the surrounding air Superior

Nose Palate – the structure that separates the nasal cavity from the oral cavity Hard palate – supported by bone Soft palate – not supported by bone; posterior part

Nose Paranasal sinuses Four sinuses Lighten the skull Act as resonance chambers (amplifies sound) for speech Produce mucus which drains into the nasal cavities Four sinuses Frontal Ethmoid Sphenoid Maxillary

Nose The suctioning effect created by nose blowing helps to drain the sinuses The nasolacrimal ducts, which drain tears from the eyes, also empty into the nasal cavities

The Boy Who Cries Blood http://abcnews.go.com/GMA/video?id=8460654

Pharynx The pharynx (throat) is a passageway for food and air The pharynx is divided into three regions Nasopharynx - the passage that connects the nasal cavity to the top of the throat Oropharynx –the part of the pharynx between the soft palate and the epiglottis Larynopharynx –the lowest portion of the pharynx; near the larynx

Pharynx Tonsils – trap and remove any bacteria or other pathogens entering the throat Tonsillitis – a condition when tonsils become congested with bacteria and become red, swollen, and sore Tonsil stones

Pharynx Three types of tonsils Pharyngeal tonsils (adenoids) – located high in the nasopharynx Palatine tonsils – located in the oropharynx at the end of the soft palate Lingual tonsils – located at the base of the tongue

Pharyngeal tonsil Palatine tonsil Lingual tonsil

Larynx Larynx – voice box Thyroid cartilage – the largest of the hyaline cartilage (Adam’s apple) One theory of “Adam’s apple”: Adam ate a piece of the forbidden fruit that got stuck in his throat

Larynx Epiglottis – protects the superior opening of the larynx When food is swallowed, the larynx is pulled upward and the epiglottis blocks the larynx Food enters the esophagus and not the larynx Breathing stops when swallowing occurs

Larynx

Larynx Vocal cords (or vocal folds) – part of the mucous membrane of the larynx forms a pair of folds Glottis – the slit-like passageway between the vocal cords

Glottis

Larynx Laryngeal Video·stro·bos·co·py Endoscopy performed with an intermittent (occurring at irregular intervals) light at a frequency that approximates the frequency of movement of the object visualized so that it appears to be motionless; useful in analyzing vocal fold structure and motion.

Trachea Trachea – (windpipe) Lined with cilia The cilia propel contaminated mucus away from the lungs to the throat where it can be swallowed or spat out The trachea is rigid because its walls are reinforced with C-shaped rings of hyaline cartilage The unprotected area of the trachea is adjacent to the esophagus

Trachea Smoking inhibits ciliary activity and destroys the cilia Without these cilia, coughing is the only means of preventing mucus from accumulating in the lungs

Non-smoker Smoker (10+ years)

Heimlich maneuver Should ask for permission before performing on an individual…

Primary Bronchi Primary bronchi – formed by the division of the trachea The right primary bronchus is wider, shorter, and straighter than the left The air is warm, cleansed of most impurities, and well humidified when it reaches the bronchi

Lungs Composition of lungs Primary bronchus Secondary bronchus Tertiary bronchus Bronchiole Terminal bronchiole Alveoli Alveolus – air sac; gas exchange occurs here Oxygen and carbon dioxide undergo diffusion The exterior of alveoli are covered with capillaries

Lungs Right lung The right side is larger than the left side Left lung Superior lobe Middle lobe Inferior lobe The right side is larger than the left side Left lung Superior lobe Inferior lobe Cardiac notch - a depression where the heart sits Apex – the narrow portion of the lung Base – the broad portion of the lung

Apex Cardiac notch Base

Lungs Visceral pleura – the membrane that lies against the lungs Parietal pleura – the membrane that lines the walls of the thoracic cavity The membranes secrete pleural fluid which reduces friction of the lungs and the thorax wall during breathing

Mechanics of Breathing Ventilation Mechanical process of pulling air in and out using muscles and pressure Respiration Chemical inflation & deflation of lungs and cellular respiration in each cell

Mechanics of Breathing Inspiration (or inhalation) – air flows into the lungs The diaphragm contracts (moves down) allowing air to enter the lungs Expiration (or exhalation) – air leaves the lungs The diaphragm relaxes (moves up) forcing air out of the lungs