Unit 2 - Respiratory System Flashcards
List the principal structures of the ventilatory system
Nose
Mouth
Pharynx
Larynx
Trachea
Bronchi
Bronchioles
Lungs
Alveoli.
Outline the functions of the conducting airways
(1) low resistance pathway for airflow - provide a clear path for air to travel
(2) Defense against chemicals and other harmful substances - the lining of the tracheobronchial system, the larynx
(3) Warming and moistening the air - the combination of cilia and mucous in the nasal airway helpstofilter out solid particles from theair, also warms and moistens the air
Define the term pulmonary ventilation
inflow and outflow of air between the atmosphere and the lungs (also called breathing).
Define the term total lung capacity (TLC)
volume of air in the lungs after a maximum inhalation – measured in litres.
Define the terms vital capacity (VC)
maximum volume of air that can be exhaled after a maximum inhalation.
Define the term tidal volume (TV)
volume of air breathed in and out in any one breath.
Define the term expiratory reserve volume (ERV)
volume of air in excess of tidal volume that can be exhaled forcibly.
Define the term inspiratory reserve volume (IRV)
additional inspired air over and above tidal volume.
Define the term residual volume (RV).
volume of air still contained in the lungs after a maximal exhalation.
Explain the mechanics of ventilation in the human lungs.
Inspiration
the process of taking air into the lungs. it is the result of muscle contraction. the diaphragm contracts and the thoracic cavity increases in volume. decreases the intraalveolar pressure so that air flows into the lungs.
Expiration
the process of letting air out of the lungs. the relaxation of the diaphragm and elastic recoil of tissue decreases the thoracic volume and increases the intraalveolar pressure.
Explain the mechanics of ventilation in the human lungs in fitness
there is a need for additional oxygen. The rate of breathing will increase. muscle of the crest wall, abdomen and shoulders will assist in increasing the area (volume) of the chest cavity to bring in more air. They will also assist in compressing the chest cavity to decrease the area and increase the pressure so more air can be exhaled.
Describe nervous and chemical control of ventilation
tightly monitored and controlled in the brainstem (specifically the medulla), relies on a delicate sensory-effector system.
Sensors:monitor specific information about dissolved gases and other factors and are responsible for relaying this information to the medulla.
Central Controller:located in the medulla it receives sensory information and relays a bodily response to correct any abnormality detected.
Effectors:receive information from the brain and “effect” a change in some physiologic way to correct for the abnormalities detected.
Medulla is the central controller that regulates the normal respiratory cycle. This portion of the brain receives input from various “sensors” to either increase or decrease respiration (the amount of breaths), and the duration of each breath (how much air we take into the lungs).
The overall goal of the central control mechanism is to maintain the correction oxygenation state of the blood to maximize oxygenation of body tissues.
breathing rate increases during exercise as the expiratory centre sendsimpulses to the expiratory muscles (internal intercostals) which speedsup the expiratory process;increase CO2 causes the acidity of the blood to increase (decrease bloodpH)/a change in acidity of the blood is detected by chemoreceptorswhich send nerve impulses to the respiratory muscles which increasethe rate of ventilation (faster/deeper);
Describe nervous and chemical control of ventilation during exercise.
breathing rate increases during exercise as the expiratory centre sendsimpulses to the expiratory muscles (internal intercostals) which speedsup the expiratory process;increase CO2 causes the acidity of the blood to increase (decrease bloodpH)/a change in acidity of the blood is detected by chemoreceptorswhich send nerve impulses to the respiratory muscles which increasethe rate of ventilation (faster/deeper);
