PHYSIOLOGY OF •Respiration: definition, stages of respiration.
RESPIRATION •Mechanisms of lung ventilation.
•Diffusion processes in lungs and tissues and transport
of oxygen and CO2 by blood.
,Respiration: Definition.
Stages of Respiration
Respiration in higher animals
and humans is understood as
a complex of processes that
provide delivery of oxygen to
the internal environment of
the body, utilization of oxygen
for oxidation of organic
substances with production of
CO2, and release of CO2
from the body into the
external environment.
,Stages of
respiration:
1st stage. Ventilation of lungs
– exchange of gases between
alveolar gas and atmospheric
air;
2nd stage. Exchange of
gases between alveoli and
blood;
3d stage. Transport of oxygen
from lungs to tissues, and of
CO2 from tissues to lungs;
4th stage. Gas exchange
between blood and tissues.
5th stage. Tissue, or internal,
respiration.
, Ventilation of
Lungs
Contraction of external
intercostal muscles changes
the volume of the chest in the
forward and sagittal directions:
the ribs and the sternum go
upward, and the ribs slightly
diverge. The diaphragm and
external oblique intercostal
muscles provide inspiration at
relative physiological rest.
Expiration at physiological rest
is a passive process resulting
from relaxation of these
muscles.
RESPIRATION •Mechanisms of lung ventilation.
•Diffusion processes in lungs and tissues and transport
of oxygen and CO2 by blood.
,Respiration: Definition.
Stages of Respiration
Respiration in higher animals
and humans is understood as
a complex of processes that
provide delivery of oxygen to
the internal environment of
the body, utilization of oxygen
for oxidation of organic
substances with production of
CO2, and release of CO2
from the body into the
external environment.
,Stages of
respiration:
1st stage. Ventilation of lungs
– exchange of gases between
alveolar gas and atmospheric
air;
2nd stage. Exchange of
gases between alveoli and
blood;
3d stage. Transport of oxygen
from lungs to tissues, and of
CO2 from tissues to lungs;
4th stage. Gas exchange
between blood and tissues.
5th stage. Tissue, or internal,
respiration.
, Ventilation of
Lungs
Contraction of external
intercostal muscles changes
the volume of the chest in the
forward and sagittal directions:
the ribs and the sternum go
upward, and the ribs slightly
diverge. The diaphragm and
external oblique intercostal
muscles provide inspiration at
relative physiological rest.
Expiration at physiological rest
is a passive process resulting
from relaxation of these
muscles.
