Lesson 5 (Chapter 2: Structures of the Respiratory System) Flashcards
Nasal Cavity
Air enters the nasal cavity through two openings called the nares, or nostrils. The nasal cavity is lined with a mucous membrane. The mucus that lines the mucous membrane provides a physical barrier against invasion by pathogens (harmful microorganisms), dust, and pollen. It is sticky and traps these particles when they enter the nasal cavity. In addition, inhaled air is warmed and moistened by the tissue that lines the nasal cavity.
Olfactory Receptors
Humans have 12 million receptor cells for smell in the extreme upper region of the nasal cavity (olfactory region). By contrast, dogs have 4 billion receptor cells, which is why they can be trained to sniff for drugs, explosives, and dead bodies.
Paranasal Sinuses
Paranasal sinuses are air-filled cavities that surround the nasal cavity. They reduce the skull’s weight, produce mucus, and influence voice quality by acting as resonating chambers. The four paranasal sinuses are maxillary, ethmoid, sphenoid, and frontal.
Pharynx
Commonly known as the throat, the pharynx is a passageway that serves both the respiratory and digestive systems. The pharynx receives air after it passes through the nose or mouth.
Larynx
Commonly known as the voice box, the larynx lies between the pharynx and the trachea. Air exhaled from the lungs passes through the larynx and vibrates the vocal folds to create sound.
Trachea
Commonly known as the windpipe, the trachea is the main airway to the lungs. The trachea divides into two large branches (primary bronchi), which channel air to the right or left lung.
Lunga
Two lungs expand and contract to supply oxygen to tissues all over the body and dispose of carbon dioxide. A double-layered serous membrane called the pleura encloses each lung. This membrane also divides each lung into sections called lobes. The right lung has three lobes. The left lung has two lobes to make room for the heart.
Bronchi and Bronchioles
The bronchi and bronchioles are a network of intricate passages that supply the lungs with air. The primary bronchi run into each lung before branching off into smaller bronchi. These smaller bronchi subdivide into increasingly smaller branches called bronchioles. Each bronchiole further splits into many smaller branches called terminal bronchioles. Finally, the millions of tiny terminal bronchioles conduct air to the alveoli of the lungs.
Alveoli
Alveoli (air sacs) are very small, grapelike clusters at each bronchiole’s end. Exchange of oxygen and carbon dioxide between the air in the lungs and the blood in the capillaries occurs across the walls of the millions of alveoli in each lung.
Diaphragm
The diaphragm is a muscular sheet between the base of the lungs and the abdominal cavity. The contraction and relaxation of this muscle makes breathing possible.
Py/o
Pus
Melan/o
Black
Myc/o
Fungus
Hem/o
Blood
Bronch/o, Bronch/i
Brouchus
Thorac/o, Thor/a
Chest or chest cavity
-centesis
Surgical puncture for the removal of fluid
-pnea
Breathing
-ptysis
coughing or spitting
-rhea
flow or discharge
-rrhagia
bleeding or hemorrhage
-scopy
Process of viewing or examining with a lighted instrument called a scope
-phonia
Voice or sound
-osis
Abnormal condition
Dys-
Abnormal, painful, labored or defective
A-, An-
Without, absence of or lack of
