Respiratory System Flashcards
Define ventilation
Getting air into and out of the lungs
Define External respiration
Gaseous exchange between the lungs and the blood
Define Internal respiration
Gaseous exchange between the blood and the cells
Define Cellular respiration
Metabolic reactions that take place in a cell to obtain energy from fuels
Define Gaseous exchange
the movement of oxygen from the air into the blood, and carbon dioxide from the blood into the air
Where does Gaseous exchange take place ?
At the alveoli
What is the pathway of air ?
Nose/Mouth > Pharynx > Larynx > Trachea > Right/Left Bronchus > Bronchioles > Alveoli
What characteristics of the alveoli help with diffusion ?
Large surface area
One cell thick
Good blood supply
Define Tidal Volume and how exercise affects it ?
Volume of air breathed in or out during normal breathing
Increases
Define Inspiratory reserve volume (IRV) and how exercise affects it ?
Volume of air that can be forcibly inspired after a normal breath
Decreases
Define Expiratory reserve volume (ERV) and how exercise affects it ?
Volume of air that can be forcibly expired after a normal breath
Slight Decrease
Define Residual volume and how exercise affects it ?
Volume of air that remains in the lungs after maximum expiration
Remains the same
Define Minute ventilation and how exercise affects it ?
Volume of air breathed in or out per minute
Large increase
Define Vital capacity
The greatest volume of air that can be expelled from the lungs after taking the deepest possible breath
% of gases inspired at rest
Oxygen = 21
Carbon Dioxide = 0.03
Nitrogen = 79
Water Vapour = Varied
% of gases expired at rest
Oxygen = 16.4
Carbon Dioxide = 4.0
Nitrogen = 79.6
Water Vapour = Saturated
% of gases expired during exercise
Oxygen = 14
Carbon Dioxide = 6
Nitrogen = 79
Water Vapour = Saturated
What are the partial pressures of oxygen and carbon dioxide at the alveolus ?
O2:
100mm Hg (A) > 40 mm Hg (B)
CO2:
40mm Hg (A) < 46 mm Hg (B)
What are the partial pressures of oxygen and carbon dioxide at the cell ?
O2:
100mm Hg (B) > 5 mm Hg (C)
CO2:
40mm Hg (B) < 46 mm Hg (C)
Define Pulmonary ventilation
Breathing
What 3 factors affect regulation of breathing ?
Neural control
Chemical control
Hormonal control
How do neural and chemical control affect breathing ?
Increased blood acidity is detected, sends a message to the respiratory centre, brain sends an impulse
Where and what is the respiratory centre ?
In the medulla oblongata
Controls rate and depth of breathing
Made up of inspiratory and expiratory centre
Sends an impulse through the phrenic nerve
What other factors affect neural control ?
Proprioceptors (↑ Movement = ↑ Breathing)
Baroreceptors (↓ Blood pressure = ↑ Breathing)
Stretch Receptors (Prevents over-inflation of lungs)
How does hormonal control affect breathing ?
Adrenaline is transported in blood
Referred to as the body’s activator
Breathing rate increase as an anticipatory rise
How does smoking affect the respiratory system ?
Irritation of trachea and bronchi.
Reduces lung function
Swelling and narrowing of the lungs
Damages cilia
Excess mucus build up
Can damage alveoli
Increases risk of COPD (chronic obstructive pulmonary disease).
Reduces oxygen-carrying capacity of blood due to carbon monoxide
