Human Anatomy CH 22 Flashcards
What are the 2 basic functions of the respiratory system?
- Supplies body with oxygen
- Disposes of carbon dioxide
What are the 4 processes involved in respiration?
- Pulmonary ventilation
- External respiration
- Transport of respiratory gases
- Internal respiration
What are all of the respiratory organs?
- Nose, Nasal Cavity, and Paranasal Sinuses
- Pharynx, larynx, trachea
- Bronchi and smaller branches
- Lungs and alveoli
What are the organs of the respiratory system divided into?
- Conducting Zone
- Respiratory Zone
What are the functions of the Conducting Zone?
- Respiratory passageways that convey air
- Filter, humidify, and warm incoming air
What is the of the Respiratory Zone? What structures does it include?
- Site of gas exchange in the lungs
- Includes structures that have alveoli
What are the 4 main functions of the nose?
- Provides an airway for respiration
- Moistens and warms air
- Filters inhaled air
- Resonating chamber for speech
What are 3 characteristics of the nose?
- Houses olfactory receptors
- Size variation due to differences in nasal cartilages
- Skin of nose is thin and contains many sebaceous glands
What is another ward for “external nares”?
Nostrils
What divides up the nasal cavity? What is the nasal cavity continuous with?
- Nasal septum
- Nasopharynx
What is another word for “posterior nasal apertures”?
Choanae
What are the 2 types of mucous membrane?
- Olfactory mucosa
- Respiratory mucosa
Name 2 characteristics of Olfactory Mucosa
- Near roof of nasal cavity
- Houses olfactory (smell receptors)
Name 2 characteristics of Respiratory Mucosa
- Lines nasal cavity
- Epithelium is pseudostratified ciliated columnar
What type of cells does the Respiratory Mucosa have? Where are these cells located?
Goblet cells within epithelium
What underlying layer does the Respiratory Mucosa have?
Lamina Propria
What are the glands in the Lamina Propria called? What kind of cells do they contain?
- Compound tubuloalveolar glands
- Mucous and serous cells
Sensory nerve endings from which nerve supply the respiratory mucosa?
Cranial Nerve V
Cilia of the epithelium of the respiratory mucous moves ___________ to the ______________
Contaminated mucus posteriorly; pharynx
What happens after contaminated mucous is moved to the pharynx?
Filtered particles and mucus are swallowed to eventually be digested by digestive juices in the stomach
The superior and middle nasal conchae are part of what bone?
Ethmoid bone
What inferior nasal conchae does what?
Separate bone
What projects medially from the lateral wall of the nasal cavity?
3 Nasal Conchae
What happens when inhaled air twists and turns through the nasal conchae?
Air’s particulate matter is deflected to mucus-coated surface where it becomes trapped
What happens during inhalation?
Incoming air is filtered, heated, and moistened
What happens during exhalation?
Moisture and heat are reclaimed
The paranasal sinuses are located within which bones?
Frontal, Maxillary, Sphenoid, Ethmoid bones
Where do the paranasal sinuses open into?
Nasal Cavity
What is the funnel-shaped passageway that connects the nasal cavity and mouth?
Pharynx
The Pharynx is divided into what 3 sections?
HINT: Named by location
- Nasopharynx
- Oropharynx
- Laryngopharynx
What changes along the length of the Pharynx?
Type of mucosal lining
What is superior to the point where food enters?
Nasopharynx
Which structure is only an air passageway?
Nasopharynx
Which structure closes off during swallowing?
Nasopharynx
What reflects superiorly in relation to the Nasopharynx?
Uvula
What organ is located on the posterior wall and destroys entering pathogens?
Pharyngeal tonsil (adenoids)
The Nasopharynx contains the opening to…?
Pharyngotympanic tube (Auditory tube)
What organ provides some protection from infection?
Tubal Tonsil
What is an archlike entranceway that extends from soft palate to epiglottis?
Fauces
What type of tissue is the Oropharynx made out of?
Stratified squamous epithelium
What are the 2 types of tonsils in the oropharynx and where are they located?
- Palantine Tonsils - In lateral walls of the fauces
- Lingual Tonsils - Cover the posterior surface of the tongue
What is the passageway for both food and air?
Laryngopharynx
What type of tissue is the Laryngopharynx consisted of?
Stratified squamous epithelium
What is continuous with the esophagus and larynx and extends to inferior boundary of cricoid cartilage?
Laryngopharynx
The Larynx extends from which vertebrae to which vertebrae?
4th to 6th cervical vertebrae
What is inferiorly continuous with the trachea?
Larynx
What attaches to the hyoid bone superiorly and opens into the laryngopharynx?
Larynx
What is the framework of the Larynx?
Framework is arrangement of nine cartilages
What are the 3 functions of the Larynx?
- Voice production
- Provides an open airway
- Routes air and food into the proper channels
What is shield-shaped and forms the laryngeal prominence (Adam’s Apple)?
Thyroid Cartilage
What are the 3 pairs of small cartilages?
- Arytenoid cartilages
- Corniculate cartilages
- Cuneiform cartilages
What structure tips inferiorly during swallowing?
Epiglottis
What are the 2 vocal ligaments of the larynx? What are their “functions”?
- Vocal folds (True vocal cords) - Act in sound production
- Vestibular folds (False vocal cords) - No role in sound production
What is the medial opening between the vocal folds called?
Rima gottidis
What is the medial opening between the vocal folds called?
Rima gottidis
What are the 2 tissues of the larynx? What portion are they apart of?
- Stratified squamous - Superior portion
- Pseudostratified ciliated columnar - Inferior portion
What 2 things happen during voice production?
- Length of the vocal cords changes with the pitch
- Loudness depends on the force of air across the vocal folds
What is abdominal straining, such as straining to defecate, abdominal muscles contraction, the glottis closing to prevent exhalation, raising intrathoracic and intra-abdominal pressure called?
Valsalva’s manuveur
How does Valsalva’s Manuveur affect the body?
Evacuates the rectum and helps stabilize trunk of the body when lifting a heavy load
What is the larynx innervated by?
Recurrent laryngeal nerves, which are a branch of the vagus nerve
What descends into the mediastinum?
Trachea
What are the C-shaped cartilage on the trachea used for?
Keeps the airways open
Where is the trachealis located?
Between open ends of C-shaped cartilage rings along length of posterior trachea
What is the carina?
Marks where trachea divides into two primary bronchi
What type of tissue is the carina made out of?
Pseudostratified ciliated columnar
What is the bronchial tree?
Extensively branching respiratory passageways
What are the largest bronchi?
Primary bronchi (main bronchi)
What is the defining feature of the right main bronchi compared to the left bronchi?
Wider and shorter than the left
How many secondary (lobar) bronchi are on the left and right respectively?
3 on the right
2 on the left
What branches into each lung SEGMENT?
Tertiary (segmental) bronchi
Define bronchiole
Little bronchi, less than 1mm in diameter
How large are terminal bronchioles?
Less than 0.5mm in diameter
As the conducting tubes become smaller, what 3 things happens?
- Supportive connective tissue changes by having C-shaped rings be replaced by cartilage plates
- Epithelium changes
- Smooth muscle becomes important
When the epithelium changes due to the conducting tubes becoming smaller, what tissue type is it initially? What does it change into?
- Initially pseudostratified ciliated columnar
- Replaced by simple columnar
- Replaced by simple cuboidal epithelium
As a result of the conducting tubes becoming smaller, how does the smooth muscle become important?
- Airways widens with sympathetic stimulation
- Airways constricts under parasympathetic direction
What does the Respiratory Zone consist of?
Air-exchanging structures; respiratory bronchioles and alveoli
What is the function of respiratory bronchioles?
Gas exchange occurs where smooth muscle is absent
Where do respiratory bronchioles branch from? Where do they lead to?
Branch from: Terminal bronchioles
Lead to: Alveolar ducts, which lead to alveolar sacs
About how many alveoli account for the tremendous surface area having to do with gas exchange?
~400 million
What is the surface area of alveoli?
1500 square feet (~140 square meters)
What are the 3 types of alveolar cells?
- Type I alveolar cells
- Type II alveolar cells
- Alveolar macrophages
What type of tissue makes up Type I alveolar cells? How many layers are there?
Single layer of simple squamous epithelial cells
What are Type I alveolar cells surrounded by?
Basal lamina
What is the respiratory membrane made out of?
Alveolar and capillary walls plus their basal lamina form
What cells secrete surfactant? What is the function of surfactant?
Type II alveolar cells
Surfactant reduces surface tension within alveoli
What type of tissue makes up Type II alveolar cells?
Cuboidal epithelial cells
What cells are scattered among type I alveolar cells?
Type II alveolar cells
What is the function of alveolar macrophages?
Remove tiniest inhaled particles
Where do alveolar macrophages migrate to? HOW do they migrate there?
Bronchi
Ciliary action takes them to pharynx
What are alveoli surrounded by?
Elastic fibers
Alveoli are interconnected by way of ___________
alveolar pores
Internal surfaces are a site for free movement of ______________
alveolar macrophages
What are the 6 major landmarks of the lungs?
- Apex
- Base
- Hilum
- Root
- Left lung
- Right lung
What is the superior tip of the lung?
Apex
What is the concave inferior surface of the lung?
Base
What is the region where blood vessels, bronchi, and nerves enter and exit the lungs called?
Hilum
What is the Hilum?
Indentation on the mediastinal surface
The structures that enter and leave the lung at the hilum are called _____
Root
What structures is the root consisted of?
Blood vessels, bronchi, and nerves
What divides the superior and inferior lobes of the left lung?
Fissure oblique
What is the depression that accommodates the heart?
Cardiac notch
What are the 2 fissures of the right lung?
Oblique and horizontal fissures
What delivers oxygen-poor blood to the lungs?
Pulmonary arteries
What carries oxygenated blood to the heart?
Pulmonary veins
What 3 fibers innervates the lungs? What are their functions?
- Parasympathetic - Constrict airways
- Sympathetic - Dilate airways
- Visceral sensory fibers
What is the double-layered sac surrounding each lung? Which one is deeper and which one is more superficial?
- Parietal pleura - Superficial layer
- Visceral pleura - Deep layer
What is the potential space between the visceral and parietal pleurae?
Pleural cavity
What are the 2 things the pleurae help divide within the thoracic cavity?
- Central mediastinum
- Two lateral pleural compartments
What are the 2 phases (and 2 names) of pulmonary ventilation?
- Inspiration - Inhalation
- Expiration - Exhalation
What happens during inspiration?
- Volume of thoracic cavity increases
- Decreases internal gas pressure
What happens to the diaphragm during inspiration? What about the intercostal muscles?
- Diaphragm flattens
- Contraction raises the ribs
What 4 muscles does deep inspiration require?
- Scalenes
- Sternocleidomastoid
- Pectoralis minor
- Erector spinae - extends the back
What is a chiefly passive process?
Quiet Expiration
What 3 actions happen during quiet expiration?
- Inspiratory muscles relax
- Diaphragm moves superiorly
- Volume of thoracic cavity decreases
What is an active process?
Forced expiration
Forced expiration is produced by _______ of what muscles?
Contraction
1. Internal and external oblique muscles
2. Transversus abdominis muscle
What is the most important respiratory center?
VRG
What does VRG stand for?
Ventral respiratory group
Where is the VRG located? What generates respiratory rhythm?
- Reticular formation in the medulla oblongata
- Neurons
What is the function of the respiratory center (VRG)?
Generate baseline respiration rate
Where are the central chemoreceptors located?
Medulla
Where are peripheral chemoreceptors located?
Aortic and carotid bodies
What are chemoreceptors sensitive to?
Rising and falling oxygen levels
What is a type of allergic inflammation?
Bronchial asthma
What is bronchial asthma caused by?
Hypersensitivity to irritants in the air or to stress
What are the 2 things asthma attacks are characterized by?
- Contraction of bronchiole smooth muscle
- Secretion of mucus in airways
What respiratory disorder is an inherited disease?
Cystic Fibrosis (CF)
In cystic fibrosis, what happens?
Exocrine gland function is disrupted
How is the respiratory system of someone with Cystic Fibrosis affected?
Viscous mucus is oversecreted
What happens in Chronic Obstructive Pulmonary Disease (COPD)?
Airflow into and out of the lungs is difficult
COPD is prevalent in what individuals?
Those with a history of smoking
What 2 disorders are COPD disorders?
- Obstructive emphysema
- Chronic bronchitis
By week 4 of development, what appears? What do they invaginate?
Olfactory placodes appear and invaginate to form olfactory pits
The trachea, bronchi, and bronchi subdivisions are formed by what?
Laryngotracheal bud
How much of the alveoli are present at birth?
One-sixth
What 2 things happen to people who begin smoking as teenagers?
- Lungs never fully develop
- Additional alveoli never form
As the respiratory system ages, what 5 things occur?
- Number of glands in nasal mucosa declines
- Nose dries and produces thickened mucus
- Thoracic wall becomes more rigid
- Lungs lose elasticity
- Oxygen levels in the blood may fall
