Anatomy Ch 22 the Respiratory System

1.Respiration •Pulmonary ventilation •External respiration •Transport of respiratory gases •Internal respiration 2.Contains receptors for sense of smell 3.Produces vocal sounds

Conducting Zone •Respiratory passageways that carry air to sites of gas exchange •Filter, humidify, & warm incoming air

•Site of gas exchange in the lungs •Terminal respiratory passages

•Nose, nasal cavity and paranasal sinuses •Pharynx, larynx and trachea •Bronchi and smaller branches •Lungs and alveoli

•Lines majority of nasal cavity •Pseudostratified ciliated columnar epithelium with goblet cells
à produce mucus and propels it posteriorly •Small mucus glands
à produce mucus (~a quart / day) and lysozyme •Meatuses have numerous small openings into paranasal sinuses

•Thin skin w/ many sebaceous glands •Provides an airway for respiration •Moistens, warms, and filter air •Resonating chamber for speech •Houses olfactory receptors • •Skeletal framework: •Frontal, nasal & maxilla bones à Shape & size variation due to differences in flexible plates of hyaline nasal cartilages

•Funnel-shaped fibromuscular tube •Connects nasal cavity and mouth to larynx and esophagus •Extends from posterior nasal aperture to cricoid cartilage •Type of mucosal lining varies •Surrounded by skeletal muscle

•Lined by ciliated pseudostratified columnar epithelium •Soft palate (1) : inferior border •Uvula (2) closes passage off during swallowing to prevent food from entering nasopharynx •Pharyngeal tonsil (adenoids) (3) •Lymphoid organ high on posterior wall •Destroys entering pathogens •Contains opening to
pharyngotympanic
(auditory / Eustachian) tube (4) •Tubal tonsil •Located posterior to (4) •Swelling of pharyngeal
mucosa

•Fauces (1)—entranceway from mouth into oropharynx •Extends from soft palate to epiglottis (2)—a cartilage flap post. to tongue •Epithelium changes to stratified squamous epithelium (thick, more protective) •Both food and air pass through it •Two tonsils: •Palatine tonsils (adenoids) (3) •in lateral walls of fauces •Lingual tonsils (4) •covers posterior surface of tongue

•Passageway for both food and air •Lined with stratified squamous epithelium •Continuous with both
Esophagus •Conducts food and fluids to stomach Larynx •Conducts air to trachea
(respiratory tract)

•Provides an open airway •Voice production •Switching mechanism to route
air & food into proper channels •Larynx closed during
swallowing—pulled upward
to meet w/ epiglottis

•Epiglottis •Thyroid cartilage—forms spine anteriorly—Adam’s Apple •Cricoid cartilage—forms complete ring •3 pairs of small cartilages

•Divides into two main (primary) bronchi •Surrounded by 16 – 20 C-shaped rings of hyaline cartilage that open posteriorly and keep lumen always open •Respiratory mucosa (RM) •Submucosa (S) •Fibromusculocartilaginous layer (FMC) •Adventitia (A) •Trachealis muscle (TM)

•Carina—where the trachea branches into two main bronchi •Right main bronchus—wider and shorter than left main bronchus

•Cartilage plates—replace C-shaped rings in lobar bronchi • Cartilage completely disappears in bronchioles • Not elastin • •Epithelium: thinner (pseudostratified à simple columnar in terminal & respiratory bronchioles) •At the level of small bronchioles—little cilia remain and no mucus production • •Smooth muscle layer appears in lobar bronchi and is present throughout bronchial tree •Bronchioles do not have cartilage, but have muscular layer •Contracts during asthma attack •Absent around alveoli