Chapter 22 : Respiratory Flashcards
List the major organs of the respiratory system
- nose, nasal cavity, paranasal sinuses
- Pharynx
- Larnyx
- Trachea
- Bronchi and Branches
- Lungs and Alveoli
Speech is the result of…
Intermittent release of expired air, while opening and closing the glotis
What is pitch determined by?
Determined by the length and tension of the vocal chords
How is loudness determined?
Force of air
What chambers amplify and enhance sound quality?
Pharynx
Oral
Nasal
Sinus
How is sound shaped?
Pharynx Muscles
Tongue
Soft Palate
Lips
What is the role of the pharynx, oral, nasal and sinus cavities?
Amplify and enhance sound quality
What is the job of the conducting zone in the respiratory system?
Carry air to gas exchange area
Where does the conducting system start? And end?
Starts: Trachea
Ends: Terminal Bronchioles
What does the trachea split into?
Right and left primary bronchi
What does the conducting system include?
nasal cavity, pharynx, trachea, bronchi, and most bronchioles.
How do the main bronchi branch?
Lobar (secondary) bronchi; 3 on right, 2 on left
How do the lobar bronchi branch?
Segmental (tertiary) bronchi
How many branching levels of bronchi are there?
23
How big are the bronchioles? What are the smallest?
Less than 1mm in diameter; terminal bronchioles
What is respiration?
gas exchange
What is the respiratory zone?
Actual site of gas exchange
What makes up the respiratory zone? How big are they?
- Respiratory bronchioles
- Alveolar ducts
- Alveoli
They are microscopic
How many alveoli are there?
300 million
What is the main site for gas exchange?
Alveoli
How does gas exchange occur?
diffusion
What are the respiratory muscles? What is there role?
Diaphragm and others
Promote ventilation (air movement)
What are the two phases of pulmonary ventilation?
inspiration - gas flows into lungs
expiration - gas exits the lungs
What is atmospheric pressure? What is it at sea level/
Pressure exerted by the air surrounding the body
760 mmHg at sea level
What is negative respiratory pressure?
less than atmospheric
What is positive respiratory pressure?
greater than atmospheric
What is zero respiratory pressure?
Equal to atmospheric pressure
What is intrapulmonary pressure? How does it compare to atmospheric pressure?
Pressure in the alveoli that changes with breathing.
Eventually equalizes with atmospheric pressure
What is intrapleural pressure? How does it measure?
Pressure in the pleural cavity
Always negative pressure
What happens when intrapleural pressure is equal to pulmonary pressure?
Lungs collapse
What is transpulmonary pressure? What happens when it increases?
Pulmonary pressure - intrapleural pressure
Keeps airways open
Lungs expand when this increases
What is pulmonary ventilation?
Movement of air
How do gases travel?
Travel from an area of high pressure to low pressure
What do mechanical processes depend on?
volume changes
What do volume changes cause?
pressure changes
What do pressure changes cause?
Cause gas flow to equalize the pressure
How does pressure change when air enters the lungs?
Volume increases, pressure decreases
How does pressure change when air leaves the lungs?
Volume decreases, pressure increases
What type of process is inspiration? Why?
Active because it requires energy
What happens during inspiration?
inspiration muscles contract
thoracic cavity volume increases
intrapulmonary pressure drops to -1
air flows into lungs through pressure gradient until pressures are equal
What are two types of expiration? What type of processes are they?
Quiet - passive
Forced - Active using abdominal and inercostal muscles
What are types of forced expiration?
talking, yelling, screaming
What happens during expiration?
inspiratory muscles relax,
thoracic volume decreases
Elastic lungs recoil as intrapulmonary volume decreases
pulmonary pressure rises
What is the “functional unit” of the lung?
Alvelous
What zone are the alvelous found?
respiratory zone
What does inspiration require?
Inspiratory muscles consume energy to overcome factors that hinder air passage and ventilation
What factors affect inspiration?
Airway resistance
Alveolar surface tension
lung compliance
What is the major source of airway resistance?
Friction
Is resistance significant? Why?
No, because large airway diameter in first part of conducting zone and disappears at terminal bronchioles
What is alveolar surface tension?
Attraction between liquid molecules on alveolar walls, inhibited by surfactant
What is surfactant?
Detergent-like lipid and protein complex made by type II alveolar cells
Prevents alveolar collapse by breaking surface tension
What is lung compliance?
How much the lung volume changes with a given change in pressure
What is lung compliance diminished by?
Non-elastic scar tissue
Reduced production of surfactant
Deceased flexibility of the thoracic cage
What is a spirometer?
Used to measure respiratory capacities
Detects between obstructive and restrictive disease
What is an obstructive disease?
Increased airway resistance, like bronchitis
What is a restrictive disease?
Reduction in lung capacity due to changes in functional expansion of lung tissue, like fibrosis and TB
What are 4 respiratory volumeds?
tidal volume
inspiratory volume
expiratory volume
residual volume
What is tidal volume?
Amount of air inhaled or exhaled w/ each breath during rest
What is inspiratory volume?
Amount of air that can be forcefully inhaled after a normal tidal volume inhalation
What is expiratory volume?
Amount of air that can be forcefully exhaled after normal tidal volume exhalation
What is residual volume?
Amount of air remaining in lungs after forced exhalation
What is dead space?
Some inspired air never gets to participate in gas exchange
What is anatomical dead space?
Volume of the conducting zone conduits
What is alveolar dead space?
Alveoli that cease to act in gas exchange due to collapse or obstruction
What is total dead space?
Sum of above non-useful volumes
What is gas exchange?
Gases will move from area of high concentration to low via diffusion
When gases enter the alveoli, what are o2 and CO2 levels?
High O2, Low CO2
When gases are in the alveoli and ready to be expired, what are O2 and CO2 levels?
low O2, high CO2
Where does external respiration occur? What is it an exchange of?
In the Alveoli across the respiratory zone
Exchange of O2 and CO2
What is external respiration influenced by?
Partial pressure gradients & gas solubilities
Ventilation - perfusion coupling
Structural characteristics of respiratory membrane
What is external respiration influenced by?
Partial pressure gradients & gas solubilities
Ventilation - perfusion coupling
Structural characteristics of respiratory membrane
What is ventilation-perfusion coupling?
Efficient gas exchange happening at the same place, same time
What is ventilation?
Amount of gas reaching alveoli
What is perfusion?
Blood flow reaching alveoli
What is? Where does internal respiration occur? What blood vessels are involved?
Capillary gas exchange
Occurs in Body Tissues
In the capillaries
How do the diffusion gradients in internal respiration compare to external respiration?
Reversed
Oxygen partial pressure always lower in capillaries than fresh arterial blood
Oxygen moves into tissues, CO2 move into blood
What do neural mechanisms do? Where are they found?
Send impulses directly to respiratory muscles, 12-15 breaths/minute
Found in pons and medulla
Name 3 neural mechanisms
Pontine
Ventral medullary
Dorsal medullary
What is pontine?
Neural mechanism
Interact w/ medullary respiratory centers to smooth respiratory pattern
What is ventral medullary?
Contain rhythm generators who drive respiration
What is dorsal medullary?
Integrates peripheral sensory input and modifies rhythms
What is depth of breathing?
How actively the respiratory centers stimulate the respiratory muscles
What is rate of breathing?
How long the inspiratory center is active
How are depth and rate of breathing modified?
In response to changing body demands
What affects depth and rate of breathing?
Chemical arterial o2 below 60 mmHG Lower than normal PH Emotions, pain, stress and body temp changes inhaled pulmonary irritants
What are chemical factors affecting depth and rate of breathing?
CO2
Hydrogen Ion (H+)
O2
How does CO2 affect breathing?
Increase CO2, Increase respiration (hypercapnia)
Lack of CO2 decreases respiration (hypocapnia)
What is hyperventilation?
Depth and rate of breathing exceeds the body’s need to remove CO2
What is apnea?
NOT BREATHING - happens when CO2 is abnormally low
How does exercise affect breathing?
increases body demand for O2 in tissues and generates more CO2 to get rid of
What is Hypernea?
Increase in ventilation in response to tissue and metabolic needs
How does high altitude affect breathing?
Decrease in both atmospheric pressure and partial pressure of O2
What is AMS? How does it kick in? What are symptoms?
Acute Mountain Sickness; quick travel to about 800 ft above sea level;
Symptoms include headache, shortness of breath, nausea, dizziness; severe cases cerebral edema and death
How does diving affect breathing?
As you dive deeper, pressure increases and lungs get smaller;
What can happen when diving if you ascend too quickly?
barotrauma (Alveoli can rupture) and bends (nitrogen gas bubbles in bloodstream)
What is COPD? What are the 2 main characteristics?
uncurable Chronic Obstructive Pulmonary Disease
Most are smokers
1) Chronic bronchitis and emphysema
2) Irreversible decrease in ability to force air out of lungs
What is dyspnea?
difficulty breathing
What is asthma? What causes it?
immune response caused by active inflmmation that leads to bronchospams, airways are thickened with mucus
What is a bronchospasm?
Tightening of the smooth muscles around the bronchi
What is tuberculosis caused by? How is it treated?
Caused by bacteria called mycobacterium tuberculosis
Treated with antibiotics for 12 months
What are the symptoms of TB?
fever night sweats coughing weight loss spitting up blood
What are 90% of lung cancer cases caused by?
smoking
What are 3 common types of lung cancer?
Squamous cell carcinoma
Adenocarcinoma
Small cell carcinoma
What are 3 common types of lung cancer?
Squamous cell carcinoma
Adenocarcinoma
Small cell carcinoma
What is cystic fibrosis? How common? What causes?
most common genetic lethal disease
1 in 2400 births caused by faulty gene
What are symptoms of CF?
Abnormal mucus production
respiratory infections
lung damage over time
