Respiratory System Flashcards
What are the components of the respiratory system?
Nose, pharynx, larynx, trachea, bronchi, lungs
Where does gas exchange occur?
Only in the alveoli
What do the conducting passageways do?
Purify, humidify, and warm the incoming air
What are the functions of the resp. system?
- Gas exchange - O2 in & Co2 out
- Acid-base balance
- Production of sound
- Sense of smell
- Protect respiratory surfaces from infections
Describe the diaphragm
Diaphragm: A dome-shaped muscle located below the lungs. It contracts and flattens to enlarge the thoracic cavity, creating a vacuum that pulls air into the lungs. It relaxes to expel air from the lungs.
Describe the structure and function of the lungs and the pleural
coverings
Lobes, Alveoli and bronchi
Visceral Pleura: This inner layer covers the surface of the lungs.
Parietal Pleura: This outer layer lines the inside of the chest cavity and the diaphragm.
(Func. = lubrication, protection, & pressure gradient
Why are the lungs assymetrical?
The right lung has three lobes (superior, middle, and inferior), while the left lung has two lobes (superior and inferior). This asymmetry allows space for the heart on the left side of the chest.
Describe the structure the respiratory membrane
Type I Alveolar Cells: These are thin, flat cells that form the majority of the alveolar wall. Their thinness reduces the distance for gas diffusion.
Type II Alveolar Cells: These cells are more cuboidal and secrete surfactant, a substance that reduces surface tension within the alveoli, preventing their collapse and aiding in gas exchange.
Define Cellular respiration
Use of oxygen to produce energy and CO2
Define external respiration
gas exchange between pulmonary blood and alveoli - exterior
Define internal respiration
At systemic capillaries, gas exchange occurs between blood and cells inside the body. O2 is unloaded from blood and Co2 is loaded
Define pulmonary ventilation
PV is where the air must move into and out of the lungs so that gases in the alveoli are refreshed cont.
Explain how the respiratory muscles cause volume changes that lead
to air flow into and out of the lungs (breathing)
Exhalation: Diaphragm relaxes (moves up), internal intercostal muscles (during forced exhalation) contract, elastic recoil of lungs, thoracic volume decreases, intrapulmonary pressure increases, air flows out of the lungs.
Inhalation: Diaphragm contracts (moves down), external intercostal muscles contract (rib cage expands), thoracic volume increases, intrapulmonary pressure decreases, air flows into the lungs.
Describe the process of gas exchanges in the lungs and tissues
External Respiration (Lungs): Oxygen moves from the alveoli to the blood, and carbon dioxide moves from the blood to the alveoli.
Internal Respiration (Tissues): Oxygen moves from the blood to the tissue cells, and carbon dioxide moves from the tissue cells to the blood.
Describe how oxygen and carbon dioxide are transported in the
blood
Oxygen Transport:
Hemoglobin & Plasma
Carbon Dioxide Transport:
Bicarbonate Ions - HCO3- in plasma; Carbaminohemoglobin &
Plasma
