1.1c- Respiratory System Flashcards
Spirometer
measures the air capacity of the lungs
Tidal Volume (TV)
Normal volume of air inhaled or exhaled in a normal breath
Vital Capacity (VC)
largest volume of air that can be forcibly exhaled after maximum inspiration
Residual Volume (RV)
Amount of air remaining in the lungs after a forced exhalation
Expiratory Reserve Volume (ERV)
the volume of additional air that can be forcibly exhaled after a normal exhalation
Inspiratory Reserve Volume (IRV)
Amount of air that can be forced in after normal inspiration
Minute Ventilation equation
Breathing Rate x Tidal Volume= Minute Ventilation
Breathing Rate (F)
number of breaths per minute
Minute Ventilation (VE)
Volume of air inspired or expired per minute
Untrained performer at rest- F, VE, TV
F- 12-15 breaths per minute
TV- 0.5l
VE- 6-7.5l/min
Untrained performer in exercise- F, VE, TV
F- 40-50 breaths per minute
TV- 2.5-3L
VE- 100-150 l/min
Trained athlete at rest- F, VE, TV
F- 11-12 breaths per minute
TV- 0.5l
VE- 5.5-6l/min
Trained athlete in exercise- F, VE, TV
F- 50/60 breaths
TV- 3-3.5l
VE-160-210ml
Breathing rate and exercise
Breathing Rate & Exerise:
- It increases in proportion with exerise
- It can plateau if a steady intensity
- Breathing rate continues to increase during maximal exercise until max 50-60 breaths per min
- It decreases after exerise. The rate of which is dependent upon the intersity of exerise in order to repay oxygen debt
Minute ventilation and exercise
Minute Ventilation & Excerise
- It is a product of both F & TV therefore it increases with exercise intensity
- Can plateau during sub max exercise
- Increases prior to exercise due to anticipatory rise because of adrenaline
- Increases in proportion with exercise intensity at start of exercise
- Plateaus at steady state
- Decreases after exercise and doesn’t plateau during maximal exercise
2 pressure involved in breathing
Atmospheric and Intrapulmonary
What happens if the intrapulmonary volume changes?
the intrapulmonary pressure will change also
Intercostal muscles
Muscles which move the rib cage during breathing. Contract and relax antagonistically to allow this
Inspiration at rest
diaphragm and external intercostals contract pulling ribs up and out to increase the volume within the lungs. This decreases air pressure inside the lungs so air moves in to equalise that pressure
Inspiration during exercise
External intercostals, pectoralis minor, scalene, and sternocleidomastoid muscles assist by contracting pulling the sternum and ribs up and out further, greater increasing volume in thorax. There will the ne a greater decrease in air pressure in the lungs so more air moves in to meet this demand
Expiration at rest
external intercostals and diaphragm relax. The sternum and ribs move in and down so volume of thorax decreases. Pressure inside the lungs increases so air moves out of the lungs to equalise it.
Expiration during exercise
Internal intercostals, rectus abdominus and obliques contract to pull sternum and ribs in and down further while external intercostals and diaphragm relax. Greater decrease in thoracic cavity volume so there will be a greater increase in pressure in the lungs so more air moves out.
Which type of intercostal is used in inhalation?
External
Functions of the respiratory system
Pulmonary Ventilation and Gas exchange
External respiration
movement of oxygen into the blood and carbon dioxide into the lungs
Internal respiration
the release of oxygen to respiring cells for energy production and collection of waste products
Pathway of air
mouth -> nose -> pharynx -> larynx -> trachea -> bronchi -> bronchioles -> alveoli
makeup of blood
55% plasma, 45% cells
why is oxygen needed?
needed for cellular respiration so we can produce energy
How can oxygen be transported?
Carried with haemoglobin (97%)
With blood plasma (3%)
How carbon dioxide be transported?
Dissolved in water and carried in carbonic acid (70%)
Carried with haemoglobin (23%)
Dissolved in blood plasma (7%)
Internal gas exchange site
Blood capillary and muscle cell membrane
External gas exchange site
Alveoli and blood capillary
Gaseous exchange
The movement of gases across a membrane, for example the movement of oxygen out of the alveoli into blood capillaries.
Partial pressure (p)
The pressure exerted by an individual gas held in a mixture of gases
internal respiration
Exchange of gases between cells of the body and the blood
CO2: muscle to capillary
O2: capillary to muscle cells
External respiration
exchange of gases between lungs and blood
CO2: capillary to alveoli
O2: alveoli to capillary
RCC
Respiratory Control Centre
Role of RCC
Sends direction through motor nerves to change rate of respiratory muscle contraction
Inspiration centre
Stimulates inspiratory muscles to contract during rest and exercise.
Respiratory regulation at rest
Inspiratory centre contracts muscles via:
Intercostal nerve to external intercostals
Phrenic nerve to the diaphragm.
Nerves start at the medulla oblongata
Respiratory regulation during exercise
RCC is chemo sensitive
IC- chemoreceptors , thermoreceptors, proprioceptors
EC- baroreceptors
Chemoreceptors
Detect changes in blood acidity and carbon dioxide molecules
Thermoreceptors
respond to changes in temperature
Propriceptors
Respond to changes in motor activity or muscle activity
Baroreceptor
Detect movement of stretch receptors in lungs- inflation of lungs
