Module 9 Flashcards
what are the two phases of breathing?
- inspiration (inhalation)
2. expiration (exhalation)
which phase of breathing involves drawing oxygen rich air into the lungs?
inhalation/inspiration
which phase of breathing involves forcing oxygen poor air out of the lungs
expiration
what are the 5 functions of the respiratory system
- gas exchange
- gas conditioning
- sound production
- olfaction
- defence
what is gas exchange??
the movement of gasses across membranes
what two things are involved in external respiration?
air and blood
what two things are involved in internal respiration?
blood and cells of the body
how does external respiration work?
- inspired oxygen (o2) moves across the cellular membranes of the alveolus of the lung and its associated capillaries into the blood
- waste carbon dioxide (Co2) moves in the opposite direction and out of the body
what is gas conditioning?
gases entering the lungs need to be warmed and cleansed in order to prevent damage to the lungs
where does gas conditioning occur?
in the nasal cavities and paranasal sinuses
how does gas conditioning work?
air is swirled around to become warmed, humidified and cleansed of particulate matter via contact with the mucosal lining of respiratory epithelium
how does sounds production work?
occurs by forceful expiration of air through the vocal cords in the larynx causing them to vibrate
different ______ of the vocal cords provide different sounds with the help from the _____, _____ and ______
tensions
teeth, lips, and tongue
what kind of epithelium covers the top of the nasal cavity? What important thing is located here?
olfactory epithelium. Receptors for smell are located within this epithelium
how does olfaction work?
- when air is inhaled into the nasal cavity, airborne molecules dissolve in the mucus lining the cavity and stimulate the receptors
- signals from these receptors travel to the brain through the olfactory nerve (CN I)
what is the role of the respiratory system in terms of defense?
the course hairs of the nostrils, the ciliated cells of the respiratory epithelium, and mucus all help to trap particles and microorganisms from entering the respiratory system
what two kinds of epithelium are found in the respiratory tract?
- pseudostratified ciliated columnar epithelium
2. goblet mucus cells
what does “pseudostratified” mean in terms of epithelium?
all cells are attached to the basal lamina but only some reach the surface
what is the benefit of pseudostratified ciliated columnar epithelium in the respiratory tract?
- covered in cilia, providing an increase in surface area for conditioning air
- cilia also function to trap inhaled particles and microorganisms caught in mucus and sweep them back up the respiratory tract
where are goblet mucus cells located?
found interspersed throughout the pseudostratified epithelium
what do goblet mucus cells produce? What do they look like in staining?
- produce mucus
- stain lightly in histological image
what is the benefit of goblet mucus cells in the respiratory tract?
- the mucus forms a protective layer over the epithelium and traps particulae matter or microorganisms that may be inhaled
- also provides moisture to humidify air before it reaches the lungs
what are the two main regions of the respiratory system?
- the conducting portion
2. the respiratory portion
what is the function of the conducting portion?
transfer inhaled air from the outside world to the lung tissue and vice versa
- also where humidification and trapping of debris happens (no gas exchange)