When you inhale, air enters through the nose or mouth. As air is breathed through the nose, it is warmed, moistened and filtered by the hairs that line the nostrils. The air then passes into the nasal passages. Air from the nasal passages and mouth enters the pharynx and passes downward to the larynx.
Inhalation for deep breathing is to be done via nose
Exhalation is done through the mouth
Serves as passageway for incoming and outgoing air, filtering, warming, moistening, and chemically examining it.
Organ of smell (Olfactory receptors located in the nasal mucosa
Aids in phonation
Once the air enters the nose and mouth, it travels into the pharynx and larynx. The structures of the upper respiratory tract are moist with mucus and are lined with cilia. The CILIA constantly sweep the airways, in an upward motion, to facilitate elimination of bacteria, dust and other particles
LOCATION: at the upper end of the trachea, just below the pharynx
1. Cartilages: nine pieces arranged in a boxlike formation
Thyroid cartilage: largest (Adam’s apple)
Epiglottis (the lid cartilage) The epiglottis is a leaf-shaped, elastic structure that is attached along one edge to the top of the larynx. Its hingelike action prevents food from entering the trachea (aspiration) by closing over the glottis during swallowing. The epiglottis opens during breathing and coughing.
Cricoid (the signet ring cartilage)
2. Vocal Cord
False: folds of mucous linings
True: fibroelastic bands stretched across the hollow interior of the larynx; the paired vocal cords (folds) and the posterior arythenoid cartilages make up the GLOTTIS; the slit between the vocal cords, through which air enters and leaves the lower respiratory passages, is the rima glottidis
This armored tube allows air to pass beyond the larynx to where it divides into the left and right bronchi. The protective ‘C's of cartilage also provide protection to the digestive system's esophagus right behind it.
The larynx goes directly into the trachea or the windpipe.
The trachea is a tube approximately 12 centimeters in length and 2.5 centimeters wide.
The trachea is kept open by rings of cartilage within its walls.
Similar to the nasal passages, the trachea is covered with a ciliated mucous membrane.
Usually the cilia move mucus and trapped foreign matter to the pharynx.
After that, they leave the air passages and are normally swallowed.
The respiratory system cannot deal with tobacco smoke very keenly.
Smoking stops the cilia from moving. Just one cigarette slows their motion for about 20 minutes. The tobacco smoke increases the amount of mucus in the air passages. When smokers cough, their body is attempting to dispose of the extra mucus.
the diaphragm descends into the abdominal cavity during inspiration causing (-) pressure in the lungs
the (-) pressure draws the air from the area of greater pressure (THE ATMOSPHERE) into an area of lesser pressure (THE LUNGS)
In the lungs, air passes thru the terminal bronchioles into the alveoli to oxygenate the body tissues
At the end of inspiration, the diaphragm & intercostal muscles relax & the lungs recoil
As the lungs recoil, pressure within the lungs becomes greater than atmospheric pressure, causing the air which now contains the cellular waste products of CO2 & H2O to move from the alveoli in the lungs to the atmosphere