Chapter 23: The Respiratory System Flashcards
Respiration
The process of supplying the body with O2 and removing CO2.
Respiration Steps
- Pulmonary ventilation: breathing, the inhalation and exhalation of air and involves the exchange of air between the atmosphere and alveoli of the lungs.
- External respiration: the exchange of gases between the alveoli and the blood in pulmonary capillaries across the resp membrane. Gains O2 and loses CO2. (Think: lungs into blood and CO2 from blood into lungs)
- Internal respiration: exchange of gases between blood in systemic capillaries and tissue cells. Blood loses O2 and gains CO2.
Respiratory System Structures
Consists of 2 areas:
Upper:
Nose
Pharynx
Lower:
Larynx
Trachea
Bronchi
Lungs
Function of Resp System
- Provides gas exchanges: intake of O2 for body cells and removal of CO2 produced by body cells.
- Helps regulate pH.
- Contains receptors for sense of smell, filters inspired air, produces vocal sounds and excretion small amount of water and heat.
Nose
Specialized organ at the entrance of the resp system.
Consists of: visible external portion and internal portion inside the skull known as nasal cavity.
External Nose
Portion of the nose visible on the face
Consists of: supporting framework of bones and hyaline cartilage covered with muscle and skin, lined with mucous membranes.
Boney Framework of External Nose
Frontal bone
Nasal bone
Maxillae
Cartilaginous Framework of External Nose
Consists of:
several pieces of hyaline cartilage connect to each other and certain skull bones by fibrous connective tissues
Components:
1. Septal nasal cartilage: for a anterior portion of septum
2. Lateral nasal cartilages: inferior to the nasal bone
3. Alar cartilages: for a portion of the walls of nostrils.
3. External nares: 2 openings that lead to cavities known as as nasal vestibules
Functions of Interior Structures of External Nose
- Warming, moistening and filtering incoming air.
- Detecting olfactory stimuli
- Modifying speech vibration as they pass the large hallow resonating chamber.
Resonance
Refers to prolonging, amplifying or modifying a sound by vibration.
Nasal Cavity
Or internal nose
Is a large space internal anterior aspect of the skull
Lies inferior to the nasal a bone and superior to the oral cavity.
Lined with muscle and mucous membranes.
Divided into a larger inferior resp region and a smaller olfactory region
Nasal Septum
Divides the nasal cavity into right and left sides.
Outer portion: consists of mainly hyaline cartilage
Remainder: formed by vomer and perpendicular plate of ethmoids, maxillae and palatine bones.
Internal Nares
2 opening posteriorly it communicates with the pharynx
Where the nasal cavity merges with the external nose
Paranasal Sinus
Ducts that drain mucus
Nasolacrimal Ducts
Ducts that drain tears.
Resp Epithelium
Ciliated pseudo stratified columnar epi with numerous globlet cells.
Nasal Vestibule
Anterior portion of the nasal cavity just inside the nostrils.
Surrounded by cartilage.
Olfactory Epithelium
Consists of : olfactory receptor cells, supporting cells and basal cells in resp region.
Also contains cilia, no goblet cells.
Pharynx
Or throat
Is a passage way for air, food and water
Is a funnel shaped tube about 13 cm long.
Starts at the internal nares and extends to the level of the cricoid cartilage, the most inferior cartilage of the larynx.
Posterior to nasal and oral cavities.
Pharynx Functions
1.Passage way for air and food
2. Provides a resonating chamber for speech sound
3. Houses the tonsils which participates in immunological reactions against foreign invaders.
Pharynx Regions
Divided into 3 anatomical regions
1. Nasopharynx: superior portion
2. Oropharynx: intermediate portion
3. Laryngopharynx: inferior portion
Soft Palate
Form posterior portion of the roof of the mouth. Arched shaped muscular portion between the nasopharynx and oropharynx that is lined its mucous membrane.
Pharyngeal Tonsil
Or adenoid.
Contained in the posterior wall.
Nasopharynx
Lies posterior to the nasal cavity and extends to the soft palate.
Oropharynx
Lies posterior to the oral cavity and extends from the soft palate inferiorly to the level of the hyoid bone.
Only has one opening into it known as faucets.
Two pairs of tonsil are found here: palatine and lingual tonsils.
Both resp and digestive pathway.
Laryngopharynx
Begins at the level of the hyoid bone.
Inferior end opens into the esophagus(food tube) posteriorly and the larynx (voice) anteriorly.
Both resp and digestive pathway.
Larynx
Or voice box.
A short passageway that connects the Laryngopharynx with the trachea.
Lies midline in the neck and anterior to the esophagus and C4-C6.
Larynx Composition
Composed of 9 pieces of cartilage.
3 occur singly: thyroid,epiglottis and cricoid cartilage
3 occur in pairs: arytenoid, cuneiform, corniculate cartilage.
Arytenoid cartilages are the most important as they influenced changes in position and tension of the vocal folds.
Cavity of the Larynx
Is the space that extends from the entrance into the larynx down to the inferior boarder of the cricoid cartilage.
Laryngeal Vestibule
Portion of the cavity of the larynx about the vestibular folds.
Infraglottic Cavity
The portion of the cavity of the larynx below the vocal folds.
Thyroid Cartilage
Consists of 2 fused plates of hyaline cartilage that form the anterior wall of the larynx and five it a triangular shape.
Larger in males as it influence of male sex hormones.
Epiglottis
Structure that prevents food or water for entering the trachea
Is a large, leaf shaped piece of elastic cartilage that is covered with epithelium.
The stem is the tapered inferior portion that is attached to the anterior rim of the thyroid cartilage.
Glottis
Consists of a pair of fold of mucous membranes, the vocal fold in the larynx and the space between them called the rima glottidis.
Cricoid Cartilage
Is a ring of hyaline cartilage that forms the inferior wall of the larynx.
Arytenoid Cartilages
Paired triangular pieces of mostly hyaline cartilage located at the posterior superior boarder of the cricoid cartilage.
Helps move the vocal folds, form synovial joints with cricoid cartilages.
Corniculate Cartilages
Paired, horned shaped pieces of elastic cartilage are located at the apex of each arytenoid cartilage.
Structure of Voice Production
Muscles membranes of the larynx forms 2 folds
1. Vestibular folds (false vocal cords) superior pair. Space between the folds is rima vestibuli.
2. Vocal folds (true vocal folds) inferior pair
Laryngeal Ventricle
Is a lateral expansion of the middle portion of the laryngeal cavity inferior to the vestibular fold.
Voice Production
Vocal folds are the principal structures in voice production.
Vestibular folds do not function in voice production.
Pitch: controlled by the tension on the vocal folds. They are taught by the muscles, vibrate more rapidly and a higher pitch results.
Sound: originated from the vibration of vocal folds.
Trachea
Or windpipe
Carries air to the bronchi
16-20 C shaped rings
Is a tubular passageway for air that is about 12 cm.
Located anterior to the esophagus and extends from the larynx to the superior border of T5 and here it divides into right and left pulmonary bronchi.
Layers of Tracheal Wall
Deep to super to superficial
1. Mucosa: contains lamina propria. Provides protection against dust.
2. Submucosa: contains areolar CT containing seroma conus glands and ducts.
3. Hyaline cartilage: maintains airflow
4. Adventitia (composed of CT): joins trachea to surround tissues
Bronchi
Is divided into 2 sections: right main bronchus goes into the right lung and let main bronchus goes into the left lung.
Found at superior boarder of the T5
Right is more vertical, shorter and wider than the left.
Carina
Point or internal ridge where the trachea divides into the right and left main bronchi.
Contains mucous membrane.
One of the most sensitive of the entire larynx and trachea for triggering a cough reflex.
Lobar (Secondary) Bronchi
The main bronchi divides to form this bronchi.
One for each lobe of the lung.
The right has 3 lobes, left has 2.
Segmental (Tertiary) Bronchi
Smaller bronchi that is formed from the branching of the lobar bronchi.
Supply the specific bronchopulmonary segments within the lobes.
Bronchioles
Formed by the divided segmental bronchi.
Terminal Bronchioles
Bronchioles in turn branch repeatedly and the smallest ones branch into these even smaller tubes.
Contains: club (Clara) cells - columnar, non-ciliated cells interspersed among the epi cells.
These cells protect against harmful effect of inhaled toxins and carcinogens.
Club (Clara) Cells
Found in terminal bronchioles
Produce: surfactant
Function: as stem cells which give rise to various cells of the epithelium.
Bronchial Tree
The extensive branching from the trenches to the lungs.
Resembles and inverted tree.
Pulmonologist
Is a specialist in the diagnosis and treatment of lung disease.
Lungs
Are light as they float.
Are paired cone shaped organs in the thoracic cavity.
Separated from each other by the heart and mediastinum.
Extend from diaphragm and slightly superior to clavicles.
Base: is concave and fits over the convex area of the diaphragm
Apex: narrow superior portion of the lung.
Costal Surface: surface of lung, matches rounded curvature of ribs.
Mediastinal Surface: contains the hilum where blood vessels, lympathic vessels and nerves enter and exit.
Pleural Membrane
Or pleura.
Protective, double layer of serous membrane that encloses each lung.
Parietal Pleura
Superficial layer that lines the wall of the thoracic cavity.
Visceral Pleura
Deep layer that covers the lungs.
Pleural Cavity
Small space found between the visceral and parietal pleurae.
Contains: small amount of lubricating fluid secreted by the membranes.
Pleural Fluid
Reduces fritiction between the membrances.
Allows for them to slide easily over one another during breathing.
Causes the 2 membranes to adhere to one another.
Cardiac Notch
Contain in the left lung in which the apex of the heart lies.
This is way the left lung is smaller than the right, by 10%.
Fissures
Divides each lung into sections known as lobes.
Oblique fissures: Found in both lungs extend inferiorly and anteriorly. Separates superior and inferior lobes.
Horizontal fissures: found in the right lung.
Bronchopulmonary Segment
Portion of lung tissue that each segmental bronchus supplies.
Bronchial and pulmonary disorders that are localized here can be surgically removed without disrupting the surrounding tissue.
Lobules
Each bronchopulmonary segment contain these many small compartments.
Each lobule is wrapped in elastic CT and contains lymphatic vessel’s, an arteriole, a venule and a branch from a terminal bronchioles.
Alveolar Ducts
Formed from subdivided resp bronchioles and consists of simple squamous epi.