Human Respiratory System Flashcards
What are the external nostrils connected to?
The external nostrils open into a nasal chamber through the nasal passage.
What is the function of the pharynx?
The pharynx serves as a common passage for food and air.
What is the larynx and its function?
The larynx is a cartilaginous box that helps in sound production, hence called the sound box.
What prevents food from entering the larynx during swallowing?
The glottis can be covered by a thin elastic cartilaginous flap called the epiglottis.
What does the trachea divide into?
The trachea divides into a right and left primary bronchi at the level of the 5th thoracic vertebra.
What structures do bronchioles end in?
Bronchioles end in very thin terminal bronchioles.
What supports the trachea and bronchi?
The trachea, primary, secondary, and tertiary bronchi, and initial bronchioles are supported by incomplete cartilaginous rings.
What are alveoli?
Alveoli are very thin, regular-walled, vascularized bag-like structures formed from terminal bronchioles.
What comprises the lungs?
The branching network of bronchi, bronchioles, and alveoli comprise the lungs.
What covers the lungs?
The lungs are covered by a double-layered pleura with pleural fluid between them.
What is the function of pleural fluid?
Pleural fluid reduces friction on the lung surface.
Where is the outer pleural membrane located?
The outer pleural membrane is in close contact with the thoracic wall.
What are the two parts of the respiratory system?
The conducting part and the exchange part.
The conducting part transports air to the alveoli, while the exchange part is where gas diffusion occurs.
What is the function of the conducting part of the respiratory system?
It transports atmospheric air to the alveoli, clears it from foreign particles, humidifies it, and brings it to body temperature.
What occurs in the exchange part of the respiratory system?
The actual diffusion of O2 and CO2 between blood and atmospheric air.
Where are the lungs situated?
In the thoracic chamber, which is an anatomically air-tight chamber.
What forms the thoracic chamber?
Dorsally by the vertebral column, ventrally by the sternum, laterally by the ribs, and on the lower side by the diaphragm.
How does the anatomical setup of the lungs affect breathing?
Any change in the volume of the thoracic cavity will be reflected in the lung (pulmonary) cavity.
What are the steps involved in respiration?
- Breathing (pulmonary ventilation)
- Diffusion of gases across the alveolar membrane
- Transport of gases by the blood
- Diffusion of gases between blood and tissues.
What is cellular respiration?
Utilisation of O2 by the cells for catabolic reactions and resultant release of CO2.
What are the two stages of breathing?
Inspiration (drawing in atmospheric air) and expiration (releasing alveolar air).
We can directly alter the pulmonary volume
False we cannot directly enter the pulmonary volume any change in thoracic cavity will reflected pulmonary cavity
