Respiratory System Flashcards
Functions of respiratory system.
- exchange of O2, CO2
- olfaction (sense of smell)
- production of sound (voice)
- filtration, temp regulation, humidification of inspired air
Name the 2 functional organizational portions of the lung
1) conducting portion (only conducts air)
2) respiratory portion (conduct + respire)
What is the function of the nasal conchae?
aka “turbinates” - 3 ridges of bone projecting into nasal cavity (superior/middle/ inf); surrounded by mucus membrane
What is the function of the Eustachian tube?
Balances pressure (regulate in-breath of air) thru nasopharynx to push back onto eardrum (connected to inner ear)
Why are turbinates curled?
Maximize contact of air to mucous membrane to humidify air. Since the membrane is supplied w/ blood, the blood passing thru also warms the air. Hair on the turbinates filters the air (dust, particles).
Lowest limit of the trachea is called this.
Carina
airway splits into R/L primary bronchi
Root of the lung (function, alternative name)
- most medial surface where bronchi enters lung tissue)
- site for blood vessels, nerves, lymphatics to enter lung
- aka hilum
The right bronchi will divide into _____ segments (aka functional units) while the left bronchi will divide into _____.
Right = 10 Left = 8
WHERE do cartilaginous rings exist on the surface of the trachea?
anterior surface ONLY
esophagus on posterior - must expand when swallowing food, smooth ride down
WHY do cartilaginous rings exist on the surface of the trachea?
Chest wall expands when we breathe, creating (-) pressure inside for air to rush into lung tissue – rings ensure trachea maintains open shape for air to pass down tube.
Do bronchioles have cartilaginous rings?
No. But have a fairly good layer of smooth muscles to help regulate diameter of bronchioles.
What is the last conduction portion of the airway?
Terminal bronchioles
What comes after terminal bronchioles in the airway?
Terminal bronchioles –> respiratory bronchioles (wraps around alveoli) –> alveolar ducts –> alveolar sacs
What are the 3 structures of the airway wall?
1) CARTILAGE - larger airways; keeps airways open
2) SMOOTH MUSCLE - smaller airways; controls diameter (constriction = less airflow)
3) ELASTIC FIBERS - smaller airways& resp portion; recoil provides force for expiration (expansion+recovery of alveoli shape)
What occurs during an asthma attack?
- smooth muscle in bronchiole walls contract = constrict airways
- caused by: parasympathetic stimulation; histamine (allergic reactions-inflammatory response)
What is emphysema?
- breakdown of alveolar walls = reduced ability to expire air form lungs
- lowered SA for gas exchange = less efficiency
- abnormally large air spaces but reduced elastic coil
- causes: smoking, irritants (dust/pollution)
What type of epithelium are the NASAL CAVITY, NASOPHARYNX, LARGE AIRWAYS lined with?
Pseudostratified [columnar] epithelium
functions: protection, secretion
- mucous layer floats on serous layer
How many plasma membranes does an oxygen molecule cross to pass from air space to bind a hemoglobin molecule in a red blood cell?
5
Type I alveolar cells
Simple squamous epithelial cells - thin + delicate
Type II alveolar cells
Secrete surfactant (prevents walls from sticking together, lowers surface tension of alveolar fluid)
Respiratory distress syndrome
Type II alveolar cells not yet active (premature babies) = lack surfactant = alveoli fail to inflate = insufficient oxygenation of blood
What is the role of alveolar macrophages?
- ingest debris in alveoli –> mucous sheets toward pharynx by ciliary action. Coughed up or swallowed
T/F
Pulmonary arteries and veins run parallel to the airways.
False.
Pulmonary arteries travel and branches w/ airways but veins do not follow a specific pattern - NEED TO GET BACK TO HEART ASAP.
T/F
Under the pleura, the lymphatic network makes the lungs look black/ grey-ish.
True.
The lymph system pulls out a lot of junk/ debris. It travels in interlobular connective tissue.
T/F
Each alveolus is associated w/ a capillary network.
True.
Capillary bed surrounds each alveolus allowing respiration/ exchange of gas to occur.
