The Respiratory System Flashcards
What are the two centres within the RCC?
Inspiratory Centre- IC and Expiratory Centre- EC
What control mechanisms does the IC have?
Chemoreceptors, Proprioceptors, Thermoreceptors
What control mechanisms does the EC have?
Baroreceptors
What are the additional Inspiratory Muscles?
Sternocleidomastoid and Pectoralis Minor
What are the additional Expiratory Muscles?
Internal Intercoastal Muscles and Rectus Abdominals.
Mechanics of breathing: Inspiration at REST and EXERCISE
External Intercostals contract.
Diaphragm contracts to increase chest cavity.
Sternum and ribs move up and out.= I thoracic cavity.
Pulmonary air pressure falls below
atmospheric= air forced in.
EXRCISE- +Sternocleidomastoid and Pectoralis Minor.
Increase chest cavity= MORE air forced in.
Mechanics of breathing: Expiration at REST and EXERCISE
PASSIVE- External intercostals relax.
Diaphragm relaxes.
Sternum and ribs down and in= D thoracic cavity.
Pulmonary air pressure becomes greater than atmospheric air pressure= air forced out.
EXERCISE+ Internal Intercostals and Rectus Abdominals. Decreased chest cavity= MORE air out.
Main functions of the Respiratory System?
Pulmonary Ventilation- the inspiration and expiration of air from the atmosphere.
Gaseous Exchange- extraction of oxygen from air to bloodstream, muscles and tissues.
Where does external and internal respiration take place?
EXTERNAL = ALVEOLI INTERNAL= MUSCLE CELLS AND TISSUES
Task: external respiration of 02 and C02 at REST and EXERCISE
(REST- Diffusion gradient steepens and more volume of gas exchange takes place. ) “MORE THAN AT REST”
Task: internal respiration of 02 and C02 at REST and EXERCISE
(02- greater gradient, more than at rest due to increased need for oxygen)
(CO2- greater gradient, more than at rest due to increased need to remove waste products. )
What does the Oxyhaemoglobin Disassociation Curve show?
How much haemoglobin is saturated with O2 and how much is disassociated to the muscles.
How many oxygen molecules can fit onto one haemoglobin?
4 molecules.
As pp of C02 increases, affinity of oxygen and haemoglobin decreases to allow quicker disassociation.
Define Bohr’s Shift
A move of the oxyhaemoglobin disassociation curve to the right caused BY INCREASED ACIDITY IN THE BLOODSTREAM.
What causes the shift of the oxyhaemoglobin disassociation curve to the right?
- Increased temperature
- Increased production of C02 and therefore pp of C02.
- Increased production of lactic acid and carbonic acid that decreases pH.
