Respiratory Physiology Lecture 1.4: Steps of Respiration Flashcards
What are the steps of respiration?
- ventilation
- gas exchange
- gas transport
- gas exchange
- cellular respiration
What happens in ventilation during respiration?
Exchange of air between atmosphere and alveoli by bulk flow;
- changes in volume and pressure to promote movement from areas of high pressure to low pressure
What is the first gas exchange of respiration?
Exchange of O2 and CO2 between alveolar air and blood in lung capillaries by diffusion
- At level of respiratory membrane due to changes in pressure of O2 and CO2 in alveoli and blood
what occurs in gas transport of respiration?
transport of O2 and CO2 through pulmonary and systemic circulation by bulk flow
What is the second gas exchange of respiration?
Exchange of O2 and CO2 between blood in tissue capillaries and cells in tissues by diffusion
What is the cellular respiration?
Cellular utilization of O2 and production of CO2
respiratory airflow
ventilation
How is ventilation produced?
- CNS sends rhythmic excitatory (Respiratory) drive to respiratory muscles
- Respiratory muscles contract rhythmically and in a very organized pattern
- Changes in volume and pressures (thoracic and intrapulmonary) at the level of the chest and lung occur
- Air flows in and out via contraction and relaxation
What are the types of respiratory muscles?
- pump muscles
- airway muscles
- accessory muscles
How are muscles characterized by action?
inspiratory (INS) and expiratory (EXP) muscles
INS and EXP pump muscles
INS: diaphragm, external intercostals, parasternal intercostals
EXP: internal intercostals, abdominals
INS and EXP airway muscles
INS: tongue protruders (Genioglossus), alae nasi, muscles around airways (Pharynx, larynx)
EXP: muscles are airways (Pharynx, larynx)
INS and EXP accessory muscles
INS: sternocleidomastoid, scalene
How does the brain contribute to respiratory muscles?
brain must coordinate activity of these various muscle groups to produce efficient breathing
