Chapter 24 - Respiratory System Flashcards
What does increasing turbulence in conchae do?
Filters out airborne particles
Functions of the conchae
- Divide cavity into passages
- Support mucous membranes
- Increase surface area
- Increase turbulence
Air filled sacs within cranial bone
Sinuses
Different kinds of sinuses
- Maxilla
- Frontal
- Ethmoid
- Sphenoid
When do sinuses open into?
Nasal cavity
What are sinuses lined with?
Mucous membranes
Functions of sinuses
- Decreases weight of skull
- Produce mucus
- Resonant chambers
Shared passageway for respiratory and digestive system
Throat
Part of the throat that is above uvula and posterior to internal nares
Nasopharynx
Part of the throat that is a portion visible in a mirror
Oropharynx
Part of the throat that is between hyoid and esophagus
Laryngopharynx
Functions of the throat
- Passage for food
- Passage for air
- Sound production
Layers of the respiratory tree
- Mucosa
- Submucosa
- Hyaline cartilage
- Trachealis muscle
What is mucosa?
Goblet cells in pseudostratified ciliated columnar epithelium
What is the Submucosa?
Areolar CT and serous and mucous glands
What is Trachealis muscle?
- transverse and longitudinal smooth muscle
- more muscle as one moves closer to the lungs
Enlargement in airway at top of trachea and below pharynx
Larynx
What does the larynx do?
- routes air and food to proper channels
- surrounds and protects the glottis
- houses vocal cords
Opening in larynx
Glottis
Composition of larynx
- muscles and cartilage held together by elastic tissue
- cartilages
Types of cartilage in the larynx with meanings
Thyroid - Adam’s apple
Cricoid - support posterior larynx
Arytenoid, corniculate, and cuneiform - attach and control vocal cords
Epiglottis - projects into the pharynx and covers glottis during swallowing
Folds in mucous membrane
Vocal cords
Three facts about vestibular folds
- False vocal cords
- No sound production
- Muscles help close larynx during swallowing
True vocal cords that cause sound production
Vocal cords
Process of speaking
- Air pushed past vocal folds that cause vibrations
- Pitch controlled by changing tension of cords (tight=high)
- Volume related to force of air cords (more force = loud)
- Oral cavity, lips, and tongue changes sound
A very flexible tube
Trachea
What does the trachea connect?
Connects larynx with bronchi
Composition of the inner wall of the trachea
- ciliated mucous membrane with goblet cells
- 20 c-shaped pieces of hyaline cartilage
What does the ciliated mucous membrane with goblet cells in the trachea do?
- beat continuously
- expel mucous loaded with debris
Functions of the trachea
- filter and direct air
- cartilage rings prevent collapsing (but are still flexible)
- soft tissue in back allows esophagus to expand
Formed by the division of trachea
Bronchi
Where bronchi split
Carina
Bronchi enter lungs where?
Hilus
The branches and subdivisions of the bronchi
Primary
Secondary
Tertiary
Bronchioles
Differences between the right and left bronchus
- wider, shorter, straighter
- three parts
- superior one divides early
Branches of the tertiary bronchi
Bronchioles
How many terminal bronchioles form?
6500
Consequences of the bronchioles being mostly smooth muscle dominant and having little cartilage
Bronchodialation and Bronchoconstriction
Terminal bronchioles branch into what?
Respiratory lobules
What do respiratory lobules do?
50-80 per lobule
Branch into alveolar ducts
What does the respiratory system consist of?
- Upper respiratory system
- Lower respiratory system
What does the upper respiratory system do?
Filter, warm, and humidify air and bring it to and from the lower respiratory
What is in the respiratory system?
Nose
Nasal cavity
Sinuses
Pharynx
What does the lower respiratory system do?
Has alveoli - gas exchange surface
What is in the lower respiratory system?
Larynx Trachea Bronchi Bronchioles Alveoli
Functions of the respiratory system?
- Extensive area for gas exchange
- Move air to and from exchange surface
- Protect exchange surfaces from damages (Dehydration, temperature, pathogens)
- Produce vocalization
- Regulate blood volume, pH, pressure
Structure and function of gas exchange surfaces
- Increase the surface of the membrane
- Decrease the thickness of the respiratory membrane
- Highly vascularize the respiratory membrane — maximize concentration gradient
Explain the structures of the external nose
- Cartilage (Minor alar, major alar, and lateral nasal)
- Nasal bone
- External nares (encloses the nasal vestibule)
- Nasal vestibule is protected by hairs
- Opens into the nasal cavity
- Separated by the nasal septum
Where does the nasal cavity start and end?
Starts at the nasal vestibule and ends at the internal nares
What is the nasal cavity divided by?
Nasal septum
What makes up the nasal septum?
- Vomer
- Ethmoid
- Septal cartilage
How is the nasal cavity separated from the oral cavity?
Hard and soft palate
What is the hard palate made up of?
Maxilla and palatine bone
What lines the nasal cavity?
Mucus membrane lining
What is the olfactory region? (2)
- Superior region of the nasal cavity
- All areas with olfactory receptors
Examples of what is in the olfactory region of the nasal cavity
- Cribiform plate
- Superior nasal conchae
- Superior septum
The three projections of bone on each side of the nasal cavity
Conchae
Three parts of the conchae
Superior, inferior, middle
What bone is the conchae made out of?
Ethmoid and inferior nasal conchae bone
Grooves in between the conchae
Meatuses
Lead to alveolar sacs
Alveolar ducts
Contain several alveoli
Alveolar sacs
How many alveoli are there in a lung?
150 millions per lung
What is each alveoli associated with?
A network of capillaries
What does alveoli have an abundance of?
Elastic fibers
What type of cells is an alveolus composed of?
Pneumocyte type I and type II cells
What is the pneumocyte type I cell?
- Composed of simple squamous epithelium for gas exchange
- Moist lining aids in diffusion across the respiratory membrane
What does the pneumocyte type II cell do?
- No gas exchange
- Secrete pulmonary surfactant
What does pulmonary surfactant do?
- Fluid will lower cohesive force of water
- Alveolar walls don’t stick to each other
- Prevents collapse of alveoli
Each alveolus consists of what? (3) What do these characteristics make for?
- Basal lamina
- Capillary network
- Connective tissues
– Makes for a thin, flexible membrane
The components and meanings of the connective tissue in the alveolus
Fibroblasts –> Elastic and reticular fibers
Macrophages –> Phagocytosis
What cavity is the lungs in?
Thoracic cavity
Two membranes and the in between in lungs
Parietal pleura
Visceral pleura
Pleural cavity (in between)
Structures of the lungs
- Apex and base
- Hilus
- Lobes (2 left, 3 right, fissures separates)
- Lobes divided into lobules
All vessels and bronchi enter here
Hilus
How does breathing work?
Depends on volume changes in cavity
Volume change –> pressure change –> gases flow to equalize pressure
Two phases of breathing
Expiration and inspiration
Explain inspiration
Diaphragm and external intercostal muscles contract
Thoracic cavity expands –> pressure in pleural cavity decreases –> lungs expand into lower pressure areas –> pressure in lungs decrease –> air moves into lungs to equalize pressure
Explain expiration
Passive Process
Muscles relax –> recoil shrinks thoracic cavity –> pressure in pleural cavity increases –> lungs are compressed –> pressure in lungs decreases –> air moves out to equalize pressure
What is the passive process of expiration known as?
Tidal expiration
What muscles contract during forced respiration?
Internal intercostals
external obliques
abdominal recti
Explain forced respiration
Further shrinks thoracic cavity –> pressure in pleural cavity greatly increases –> lungs are compressed –> pressure in lungs greatly increase –> air moves out to equalize pressure
