Chapter 22 - The Respiratory System Flashcards
Functions
A. Pulmonary ventilation – breathing; air moving into and out of the lungs
B. External respiration – the movement of oxygen from the lungs to blood and opposite of CO2
C. Transport of respiratory gases – transport of oxygen to the lungs to the tissue cells (cardiovascular system); opposite of CO2
D. Internal respiration – movement of oxygen from blood to the tissue cells
Structure: Zones
- Conducting zone – includes all other respiratory passageways which provide rigid condo it’s for air to reach the gas exchange sites; they clean, humidify, and warm incoming air
- Respiratory zone – actual site of gas exchange; composed of respiratory bronchioles, alveolar ducts and the avoili
Structures: Organs - Nose
Only external visible part of the RS
a. Functions – provides an airway for respiration, moistens and warms incoming air, filters and cleans incoming are, serves as a chamber for speech, houses the olfactory (smell) receptors
Structures: Organs - Nose: External Nose
A. Bridge – root; area between eyebrows
B. Dorsum nasi – after the bridge (arch); where nasal bones ends
C. Apex – terminal part of nose (tip)
D. Alae – flair laterally (side)
Structures: Organs - Nose: Nasal Cavity
A. Nares – nostrils and allows air to pass
B. Nasal septum – midline in the nasal cavity (divides); formed by the volmer bone and the perpendicular plate of the ethmoid
C. Posterior nasal apertures – where the choana meet; it allows the nasal cavity to be continuous to be nasal pharynx
D. Roof and floor – roof is formed by ethmoid and sphenoid bone; floor is formed by the palate which separates the nasal and oral cavity
E. Nasal vestibule – superior to the nostrils; lined with skin that contains sebaceous and sweat glands and hair follicles
1. Vibrissae – hairs; filter air
F. Olfactory mucosa – mucous membrane and it lines the superior region of the nasal cavity and contains smell receptors
G. Respiratory mucosa – psudeostratisfied ciliary columnar epithelium and goblet cells; these cells along with glands produce a watery fluid which contains enzymes
1. Sensory nerve endings – richly supply the nasal mucosa and any contact with irritants triggers the sneeze reflex
2. Capillary plexuses – abundant; it underlies the nasal epithelium and helps warm incoming air
H. Nasal conchae – 3 scroll like mucosa cover projects; they protrude medially from each lateral wall of the nasal cavity; they increase mucosal surface area and they enhance air turbulence within the nasal cavity
1. Nasal meatuses – grooves found inferior to each conchea
I. Paranasal sinuses – surround the nasal cavity and located in the frontal sphenoid, ethmoid, and maxillary bones; makes skull lighter in weight and together with the cavities they help warm and moisten air
Structures: Organs - Pharynx
Throat; funnel shaped tube (5ins) runs from base of skull – C6
a. Function – connects nasal cavity and the mouth to the larynx and esophagus
Structures: Organs - Pharynx: Nasopharynx
Posterior to the nasal cavity, inferior to sphenoid bone and superior to the level of the soft palate; serves as an air passage way and is lined with psudeostratified ciliated epithelium ; it contains the opening of the auditory tube
A. Pharyngeal tonsil – adinoids found high on the posterior wall of the nasopharynx; trap and destroy pathogens which enter the nasopharynx
B. Pharyngotympanic tube – drains the middle ear and allows middle ear pressure to equalize with atmospheric pressure and opens to lateral walls of nasopharynx
C. Uvula- pendulous; moves superiorly which closes off the nasopharynx and prevents food from entering nasal cavity
Structures: Organs - Pharynx: Oropharynx
Lies posterior to the oral cavity and it’s continuous with it by an arch way; lined with stratified squamous epithelium
A. Isthmus of the fauces – arch way that connects the oral cavity and oropharynx
B. Palatine – paired and lies embedded in the oral pharyngeal mucosa of the isthmus of the fauces
C. Lingual tonsils – posterior surface of the tongue
Structures: Organs - Pharynx: Laryngopharynx
Below oropharynx; serves as a passageway for food and air, lined with stratified squamous epithelium
Structures: Organs - Larynx
Voice box (2in) from C3-C6 and superiorly it attach to the hyoid bone and it opens into the laryngeal pharynx and inferiorly it’s continuous with trachea; 9 cartilages that are connected with membranes and ligaments except for the epiglottis all cartilages are hyaline cartilage
a. Functions – provided an open airway, to act as a switching mechanism to root air and food into their proper channels, and voice productionStructures: Organs - Larynx: Structures
i. Thyroid cartilage – large shield shaped cartilage which is formed by the fusion of 2 cartilage plates
A. Laryngeal prominence – Adam’s apple; found at midline and marks the fusion point; typically larger in males due to the high testosterone amount
ii. Cricoid cartilage – found inferior to the thyroid cartilage; its ring shaped and its places on top and anchored to the trachea
iii. Arytenoid, cuneiform, and corniculate cartilages – 3 pairs of small cartilages and they form part of the lateral and posterior walls of the larynx. Arytenoids is the most important because it anchors the vocal folds (pyramid shaped)
iv. Epiglottis – 9th cartilage; its flexible spoon shaped and composed of elastic cartilage and is almost entirely covered in taste bud containing mucosa; it extends from the posterior aspect of the tongue to its anchoring point of the anterior rim of the thyroid cartilage
v. Vocal folds – true vocal cords; they’re white in color (they lack blood vessels) they contains ligaments with elastic fibers
A. Glottis – area in between the vocal folds; median opening that air passes
vi. Vestibular folds – false vocal cords; mucosal folds, a little superior to the vocal folds
Structure: Organs - Trachea
Wind pipe; descends from the larynx through the neck and into the media stena; it ends by dividing into the two main bronchi (mid thorax – about 4 ins long and ¾ diameter); its flexible and mobile
a. Histology i. Mucosa – psuedostrastified ciliated epithelia which contains goblet cells and a thick lamina propia ii. Submucosa – connective tissue layer, deep to the mucosa; it contains cero mucous glands; supported by about 16-20 C shaped rings of hyaline cartilage which in incased by adventitia iii. Adventitia – outermost layer of connective tissue b. Carina – projects posteriorly and marks the area where the trachea branches into the two main bronchi
Structure: Organs - Bronchial Tree: Bronchi
i. Right and left main (primary) bronchi – split around T7 the right main is wider, shorter and more vertical than the left; foreign objects are easier lodged here
ii. Lobar (secondary) bronchi – subdivisions of the main bronchis; 3 on the right side and 2 on the left side, each supplying a lung lobe
iii. Segmental (tertiary) bronchi – sub division of each lobar bronchi and they divide into smaller
Structure: Organs - Bronchial Tree: Bronchioles
Little bronchi; they’re smaller than 1mm in diameter
i. Terminal bronchioles – smallest bronchioles (> .5 mm in diameter) where the conducting zone ends
ii. Respiratory bronchioles – found within the lung; where the respiratory zone begins; it leads to the alveolar duct
Structure: Organs - Bronchial Tree: Alveoli
Out pouches, thin walled air sacs
i. Alveolar ducts – consists of diffusedly arranged rings of smooth muscle cells and connective tissue fibers
ii. Alveolar sacs – cluster of alveoli; this is the part after the alveolar duct
iii. Alveoli – lined by respiratory membrane; the walls are composed of a single layer of squamous epithelia cells – type 1 numo cites scattered in between are type 2 numo cites – produce cerfactin and produce type 1 numo cites
A. Respiratory membrane – has a capillary wall; gas exchange occurs due to diffusion
