what does pulmonary respiration consist of?
process of ventilation
exchange of O2 and CO2 in the lungs
what does cellular respiration consist of?
o2 utilisation and co2 production in the cells of organisms when breaking down glucose into ATP which is used for energy
glucose + oxygen = carbon dioxide + water + ATP
what is the difference between ventilation and respiration?
ventilation - movement of a volume of gas into and out of the lungs
respiration - exchange of oxygen and carbon dioxide across a membrane in either the lungs or at the cellular level
what are the main purposes of the respiration system?
gas exchange
acid-base balance regulation
homestatic regulation of body pH
vocalisation
protection from inhaled pathogens and irritating substances
what is diffusion?
movement of molecules from an area of high pressure to an area of low pressure
what are the major functions of the respiratory system?
pulmonary ventilation
external respiration
transport
internal respiration
what is pulmonary ventilation?
moving air into and out of the lungs from atmosphere
inhalation and exhalation
what is external respiration?
gas exchange between the lungs and the blood
what is meant by transport as one of the major functions of the respiratory system?
transport of oxygen and carbon dioxide between the lungs and tissues
what is internal respiration?
gas exchange between systematic blood vessels and tissues
supplies cellular respiration
what is the order of parts of the respiratory system?
oral cavity, nasal cavity and nostrills pharynx larynx trachea site of carina left/right primary bronchus left/right lung diaphragm
what are the functions and components of the conducting zone?
functions:
moves air to respiratory zone and humidifies, warms and filters
components:
trachea, bronchial tree and terminal bronchioles
what are the functions and components of the respiratory zone?
function:
exchange of gases
components:
respiratory bronchioles, alveolar ducts and alveolar sacs
what is the function of the alveolar macrophage?
keeps out dust and keeps the alveoli clean
what is the function of type 1 alveolar cells?
maintain the permeability barrier function of the alveolar membrane
comprise the major gas exchange surface of the alveolus
what is the function of type 11 alveolar cells?
produces surfactant to stop alveolus membrane sticking together
what is Boyle’s Law?
pressure of a gas in a closed container is inversely proportional to the volume of the container at a constant temperature
what is the atmospheric pressure?
760 mmHg or 1 ATM
should pressure in lungs be lower of higher than atmospheric pressure?
lower
what is the process of inhalation/inspiration?
increase size of lungs
increase volume of lungs
diaphragm flattens (contracts)
external intercostal muscles contract to elevate ribs
thoracic cavity expands
decrease pressure of alveoli (758 mmHg)
air rushes into lungs as flows down pressure gradient
what is the process of exhalation/expiration?
decrease size of lungs
decrease volume of lungs
relaxation of diaphragm
relaxation of external intercostal muscles
thoracic cavity reduces
increase alveoli pressure so greater than atmospheric pressure
air moves out of lungs
when is exhalation active?
during exercise, especially during maximal tests
what does COPD stand for and how can it be treated?
Chronic obstructive pulmonary disorder
treated by diaphragm release technique
what are some symptoms of COPD?
chronic inflammation of the airways leading to increased airway resistance
exhalation impaired
altered diaphragm, reduced motion
effectiveness of diaphragm release technique?
improves diaphragm mobility, inspiratory capacity and changes in vital capacity
what is the treatment of cervical spinal cord injury?
inspiratory muscle training
increases inspiratory muscle strength and reduces dyspnea (shortness of breath) and improves thickness of diaphragm
what is a symptom of cervical spinal cord injury?
respiratory function is impaired
what is minute ventilation and what is the symbol and equation for it?
amount per minute
Ve
Ve = Vt x f (tidal volume x frequency)
what is tidal volume and what is the symbol for it?
volume of air moved per breath
Vt
what is the breathing frequency and what is the symbol for it out?
number of breaths
f
what percentage tidal volume (Vt) reaches the respiratory zone in alveolar ventilation?
70%
alveolar ventilation refers to the amount of gas that reaches alveoli during a breath
what percentage of tidal volume (Vt) reaches the conduction zone in dead space ventilation?
30%
dead space ventilation refers to teh amount of volume of a breath that does not participate in gas exchange
what is airway resistance and how do you measure it?
the resistance of the respiratory tract to airflow during inhalation and exhalation
airway resistance (Raw) = atmospheric pressure (Patm) - alveolar pressure (Pa) / Volumetric airflow (V)
what is residual volume and what is the symbol for it?
RV
volume of air remaining in the lungs after maximal exhalation (air needed to sustain organs)
what is vital capacity and what is the symbol for it?
what is the equation used to work it out?
VC
maximum volume that can be inhaled and exhaled
= tidal volume (Vt) + inspiratory reserve volume (IRV) + expiratory reserve capacity (ERV)
what is inspiratory reserve volume and what is the symbol for it?
IRV
maximum volume of air that can be inhaled
what is expiratory reserve capacity and what is the symbol for it?
ERV
maximum volume of air that can be exhaled
what is functional residual capacity and what is the symbol and equation for it?
FRC
volume of air present in the lungs at the end of passive expiration
FRC = ERV + RV
what is TLC and what is the equation of it?
total lung capacity
6000 mL
= tidal volume + ERV + IRV + RV
what are the 2 respiratory control centres in our brains?
medulla oblongata (hindbrain)
pons (hindbrain directly above medulla)
what is the medullary rhythmicity area?
establishing or modifying patterns for breathing
what is the function of the medulla rhythmicity area (MRA) when at rest?
active - 2 seconds then diaphragm and external intercostals contract (normal inspiration)
inactive - 3 seconds then diaphragm and external intercostals relax (normal expiration)
what is the function of the medulla rhythmicity area (MRA) when forced breathing?
inspiratory area activates expiratory area
diaphragm etc. actively contract (forced inspiration)
internal and abdominal muscles contract (forced expiration)
what is the pneumotaxic area, where is it and what is its function?
superior portion of pons (active breathing and quicker)
teams with medulla rhythmicity area (MRA) to set rhythm of breathing
inhibitory impulses
prevents lungs from becoming too full with air as limimts duration of inspiration
what is the apneustic area, where is it and what is its function?
lower pons (active breathing and slower)
coordinate transition between inspiration and expiration
stimulates inspiratory area to prolong inspiration and slow rate of breathing
ONLY OCCURS when pneumotaxic area is inactive (so overriden by pneumotaxic)
voluntary control in dictating how we breathe?
motor cortex
involuntary control in dictating how we breathe?
feedback
what is the ventilation loop?
sensors to central controller to effectors
what is the role of central and peripheral chemoreceptors?
function to regulate respiratory activity
maintain pH levels
what are respiratory strecth receptors activated by and what do they do?
activated by overinflation of the lungs
facilitate Hering-Breuer reflex by inhibiting inspiration and allows expiration to occur
which neurons feedback and alter ventilatory responses?
group III and group IV
what does the lumbar intrathecal fentanyl do?
partially blocks sensory responses and reduces Vt, Ve and f
what is human physiology?
studies the mechanical, physical, and biochemical functions of normal humans or human tissues or organs