Biology Chapter 6: Respiratory System (1 Stars) Flashcards
Air is drawn in through the nares, and through the nasal cavity and ______, where it is warmed and humidified.
pharynx
Air is filtered by nasal hairs (vibrissae) and ______ membranes.
mucous
Air then enters the _____, followed by the trachea.
larynx
The trachea divides into two mainstem bronchi, which divide into ______, which divide into continually smaller passages until reaching the alveoli
bronchioles
_____ are small sacs that interface with the pulmonary capillaries, allowing gases to diffuse across a one-cell-thick membrane
Alveoli
______ in the alveoli reduces surface tension at the liquid–gas interface, preventing collapse.
Surfactant
The ______ pleura lies adjacent to the lung itself
visceral
The parietal pleura lines the _____ wall
chest
The _______ lies between these two layers and contains a thin layer of fluid, which lubricates the two pleural surfaces
intrapleural space
The _______ is a thin skeletal muscle that helps to create the pressure differential required for breathing.
diaphragm
The diaphragm and external intercostal muscles _____ the thoracic cavity, increasing the volume of the intrapleural space. This decreases the intrapleural pressure.
expand
This pressure differential ultimately expands the lungs, dropping their pressure and drawing in air from the environment. This mechanism is termed _________
negative-pressure breathing.
Inhalation is an _____ process.
active
______ may be passive or active.
Exhalation
In passive exhalation, relaxation of the muscles of inspiration and elastic recoil of the lungs allow the chest cavity to ______ in volume, reversing the pressure differentials seen in inhalation
decrease
In _____ exhalation, the internal intercostal muscles and abdominal muscles can be used to forcibly _____ the volume of the thoracic cavity, pushing out air.
active
A ______ can be used to measure lung capacities and volumes
spirometer
_______ is the maximum volume of air in the lungs when one inhales completely.
Total lung capacity (TLC)
Residual volume (RV) is the ______volume of air in the lungs when one exhales completely
minimum
_______ is the difference between the minimum and maximum volume of air in the lungs.
Vital capacity (VC)
_______ is the volume of air inhaled or exhaled in a normal breath.
Tidal volume (TV)
Expiratory reserve volume (ERV) is the volume of _______ air that can be forcibly exhaled after a normal exhalation.
additional
Inspiratory reserve volume (IRV) is the volume of additional air that can be forcibly ______ after a normal inhalation.
inhaled
_______ is regulated by the ventilation center, a collection of neurons in the medulla oblongata.
Ventilation
_______ respond to carbon dioxide concentrations, increasing the respiratory rate when there are high concentrations of carbon dioxide in the blood (hypercarbia or hypercapnia).
Chemoreceptors
The ventilation center can also respond to low oxygen concentrations in the blood (_______) by increasing ventilation rate
hypoxemia
Ventilation can also be controlled consciously through the cerebrum, although the _______ will override the cerebrum during extended periods of hypo- or hyperventilation
medulla oblongata
The lungs perform gas exchange with the blood through _____ diffusion across concentration gradients
simple
Deoxygenated blood with a high carbon dioxide concentration is brought to the lungs via the pulmonary ________.
arteries
_______ blood with a low carbon dioxide concentration leaves the lungs via the pulmonary veins
Oxygenated
The large surface area of interaction between the alveoli and capillaries allows the respiratory system to assist in thermoregulation through _______ and vasoconstriction of capillary beds.
vasodilation
Multiple mechanisms, including vibrissae, mucous membranes, and the mucociliary escalator, help _____the incoming air and trap particulate matter.
filter
______ in the nasal cavity and saliva attacks peptidoglycan cell walls of gram-positive bacteria.
Lysozyme
_______ can engulf and digest pathogens and signal to the rest of the immune system that there is an invader
Macrophages
Mucosal surfaces are covered with ____ antibodies.
IgA
_____ have antibodies on their surface that, when triggered, can promote the release of inflammatory chemicals. Are often involved in allergic reactions as well.
Mast cells
The respiratory system is involved in pH control through the _________
bicarbonate buffer system.
When blood pH _______, respiration rate increases to compensate by blowing off carbon dioxide. This causes a left shift in the buffer equation, reducing hydrogen ion concentration
decreases,
When blood pH increases, respiration rate decreases to compensate by trapping carbon dioxide. This causes a ____ shift in the buffer equation, increasing hydrogen ion concentration.
right
