Respiratory System: Respiration Cycle and Bicarbonate Buffer System Lab Flashcards
ventilation
mechanical process and involves the movement of air.
Respiration
physiological process and involves the exchange of gases in the alveoli (external respiration) and in the cells (internal respiration).
what consists of the upper respiratory tract
nose, nasal cavities, sinuses, pharynx and the part of the larynx above the vocal folds
what consists of the lower respiratory tract
larynx, the trachea, bronchi, bronchioles and the alveol
what do the trachea, bronchi, and larger bronchioles act as? and what do they do?
act as conduits and bring air to the respiratory bronchioles, alveolar ducts, and alveoli.
Gas exchange only occurs in?
the smaller, thin-walled terminal portions of the respiratory system.
Any inhaled air located in a portion of the tract that is not directly involved in gas exchange is situated within the____________?
anatomical dead space
At the beginning of inspiration (= inhalation), the diaphragm and external intercostal muscles ___________, which ________ the volume of the thoracic cavity.
contract, increases
increase in volume of the thoracic cavity is accompanied by an increase in the ____________ (i.e.,an increase in volume within the air sacs), which in turn, decreases__________(i.e., creating negative pressure within the air sacs).
intra-alveolar volume, intra-alveolar
pressure
what happens As soon as the intra- alveolar pressure falls below the atmospheric pressure?
air flows down the pressure gradient from the atmosphere through the airways and into the expanded alveolar spaces.
During inhalation, Airflow will continue until the intra-alveolar pressure is_______ to the ________ _________.
equal, atmospheric pressure.
how does expiration begin?
begins with the relaxation of the diaphragm and external
intercostal muscles which decreases the volume of the thoracic cavity to its resting position.
decrease in the thoracic cavity is accompanied by a ________in the intra-alveolar volume (i.e., a decrease in volume within the air sacs), which is turn, _________ intra- alveolar pressure (i.e., creating positive pressure within the air sacs).
decrease, increases
what happens As soon as the intra-alveolar pressure increases above the atmospheric pressure?
air flows down the pressure gradient from the alveolar spaces through the airways and into the atmosphere
T/F: During exhalation, airflow will continue until the intra-alveolar pressure is equal to the atmospheric pressure.
True
The volume of air inspired and expired can be measured using a?
spirometer
T/F: A person’s size, sex, age, and physical condition can create variation in respiratory volumes.
TRUE
Normal quiet breathing moves about ________ of air in and out of the lungs with each breath.
500 ml
Tidal Volume (TV)
volume of air inhaled or exhaled during one respiratory cycle
at rest (approx. 500 ml)
Inspiratory Reserve Volume (IRV)
volume of air that can be forcefully inhaled
after a normal tidal volume inhalation (used during deep breathing, approx. 1900 – 3300 ml).
Expiratory Reserve Volume (ERV)
volume of air that can be forcefully exhaled
after a normal tidal volume exhalation (used during deep breathing, approx. 700 –1000 ml)
Residual Volume (RV)
volume of air remaining in the lungs after maximal
exhalation (cannot be measured by spirometry)
Inspiratory capacity (IC)
maximum volume of air that can be inhaled following a
resting state (= TV + IRV).
Function Residual Capacity (FRC)
volume of air remaining in the lungs at the end
of a normal exhalation (= ERV + RV)
Vital capacity (VC)
maximum volume of air that can be exhaled after a maximal
inspiration (= TV + IRV + ERV)
Total Lung Capacity (TLC)
maximum volume of air the lungs can accommodate
or sum of all volume compartments (= TV, IRV, ERV, RV).
in the bicarbonate buffer system, why is the pulmonary ventilation necessary?
necessary for continuous oxygenation of the blood and
removal of CO2 (a waste product of cellular respiration) from the blood.
T/F: Blood pH must be relatively constant for the cells of the body to function optimally.
True
The carbonic acid–bicarbonate buffer system of the blood is extremely important because it helps do what?
stabilize arterial blood pH at 7.4.
what happens when CO2 diffuses into the blood from the tissue cells?
much of it enters red blood cells (= RBC), where it combines with water to form carbonic acid (= H2 CO3 ). This
reaction is catalyzed by the enzyme carbonic anhydrase.
H+ released into the blood by the body cells (e.g., lactic acids, ketone bodies) tend to?
lower the pH of the blood and to cause it to become acidic.
basic substances that enter the blood tend to cause the blood to become?
alkaline and causes the blood pH to rise.
Chemoreceptors
control the rate of breathing and are stimulated by a rise in blood CO2 and a consequent fall in blood pH.
hypoventilation
excessively slow or shallow breathing (increase in CO2)
hyperventilation
fast deep breathing (decrease in CO2)
in hyper and hypoventilation the buffering ability of the blood is inadequate and can result in?
respiratory acidosis or alkalosis
T/F: maintaining the normal rate and depth of breathing is important for proper control of blood pH.
true
