Respiration Flashcards
What is the primary function of the respiratory system?
To exchange oxygen and carbon dioxide between the body and the environment, thereby supplying oxygen for cellular respiration and removing carbon dioxide waste.
List the main processes involved in breathing.
Ventilation (air movement in and out of the lungs), external respiration (gas exchange in the lungs), transport of gases via the circulatory system, and internal (cellular) respiration (gas exchange at the tissue level).
What is the difference between external respiration and internal respiration?
External respiration is the exchange of gases (O₂ and CO₂) between the air in the alveoli and the blood, while internal respiration is the exchange of gases between the blood and the body’s cells.
What are the major components of the upper respiratory tract?
The nose, nasal cavity, sinuses, pharynx, and larynx.
What role does the nasal cavity play in respiration?
It filters, warms, and humidifies the air before it enters the lungs.
How do the sinuses contribute to the respiratory system?
They help reduce the weight of the skull, produce mucus to trap particles, and contribute to voice resonance.
What is the function of the pharynx?
It serves as a common pathway for both air and food, directing air to the larynx during breathing.
What is the role of the larynx in the respiratory system?
The larynx, or voice box, houses the vocal cords and helps produce sound, while also directing air into the trachea.
Name the major components of the lower respiratory tract.
The trachea, bronchi, bronchioles, and alveoli.
What is the function of the trachea?
The trachea, or windpipe, provides a clear airway for air to enter and exit the lungs.
How do the bronchi contribute to air distribution in the lungs?
The trachea splits into the right and left bronchi, which further branch into smaller bronchioles that distribute air evenly throughout each lung.
What is the role of the alveoli in respiration?
Alveoli are tiny air sacs where gas exchange occurs; oxygen diffuses into the blood, and carbon dioxide diffuses out to be exhaled.
How does the structure of alveoli facilitate gas exchange?
Their thin walls and large surface area (supported by a rich capillary network) enable efficient diffusion of gases.
What muscle plays the most important role in breathing?
The diaphragm. When it contracts, it increases the volume of the thoracic cavity, allowing air to be drawn into the lungs.
What is the role of the intercostal muscles during respiration?
The intercostal muscles help expand and contract the rib cage, assisting in both inhalation and exhalation.
Describe the process of inhalation (inspiration).
Inhalation occurs when the diaphragm contracts and intercostal muscles lift the rib cage, increasing thoracic volume and decreasing pressure, allowing air to flow into the lungs.
Describe the process of exhalation (expiration).
Exhalation occurs when the diaphragm relaxes and the rib cage falls, decreasing thoracic volume and increasing pressure, forcing air out of the lungs.
What is the role of hemoglobin in respiration?
Hemoglobin, found in red blood cells, binds oxygen in the lungs and transports it to tissues; it also helps carry carbon dioxide back to the lungs.
How is the rate of respiration regulated in the body?
The respiratory rate is primarily controlled by the respiratory center in the brainstem (medulla oblongata and pons), which responds to changes in carbon dioxide, oxygen, and pH levels in the blood.
