Respiratory System Flashcards
Structures of the respiratory system
- Nose/nostrils
- Nasal cavity
- Pharynx
- Larynx
- Trachea
- Bronchi
- Bronchioles
- Alveoli
Functions of the respiratory system
- Conducts air into and out of the lungs
- Exchanges gases between air and blood
- Humidifies air
- Warms air
- Filters air
What are saclike structures surrounded by capillaries in the lungs?
Alveoli
Where does the exchange of oxygen and carbon dioxide take place?
Alveoli
What is the respiratory membrane?
Two cell membranes that aid in diffusion
- Membrane of alveolar cells
- Membrane of cells of capillary wall
Membrane covering the outer surface of the lungs
Visceral (pulmonary) Pleura
Membrane covering the inner surface of the thoracic cavity and diaphragm
Parietal Pleura
Lubricating fluid between the two pleural membranes
Pleural Fluid
Pressure in the pleural cavity between two membranes; less than atmospheric pressure
Intrapleural Pressure
The lungs are connected by a thin film of fluid called what?
Serous fluid
Pressure inside the lung decreases as lung volume increases during inspiration; pressure increases during expiration. What is this?
Intrapulmonary pressure
Pleural cavity pressure becomes more negative as chest wall expands during inspiration. Returns to initial value as chest wall recoils. What is this?
Intrapleural Pressure
During each breath, the pressure gradients move 0.5 L of air into and out of the lungs. What is this?
Volume of breath
When you have an increase in volume of the intrathoracic cavity what else happens?
- Increase in lung volume
- Decrease in intrapulmonic pressure
- Causes air to rush into the lungs (inspiration)
When you have a decrease in volume of the intrathoracic cavity what else happens?
- Decrease in lung volume
- Increase in intrapulmonic pressure
- Causes air to rush out of the lungs (expiration)
Most important inspiratory muscle
Diaphragm
Muscles that elevate the ribs:
- External intercostals
- Scalenes
- Sternocleidomastoid
- Pectoralis Minor
Muscles that pull the ribs downward:
- Internal intercostals
- Rectus abdominis
- Internal oblique muscles of abdominal wall
Airflow can be increased by what?
- Amplifying pressure difference between 2 areas
- Decreasing resistance to airflow
What decreases the resistance to airflow in exercise?
Bronchodilation
Amount of air moved per breath
Tidal volume (greater in trained athletes)
Air remaining in passageways that is not involved in gas exchange
Anatomical Dead Space
Changes in breathing during exercise
- Increase in depth of breathing occurs first after onset of exercise
- If increase in depth not sufficient, rate of breathing will increase
Changes in tidal volume during exercise
Increases
