BIOS 255
(EDAPT WEEK 6)
Anatomy & Physiology III course with a lab
,General Functions of the Respiratory System
Introduction
Let’s start off our discussion of the respiratory system with a simple
question of : What is respiration? Can we simply define it as just
breathing? The answer is going to be no, as respiration is a multi-
step process that begins with breathing in humans. Essentially respiration
is a life process that allows for the ultimate use of oxygen in cellular
metabolism and in this module we will begin our discussion of the
respiratory system by describing those processes associated with
respiration as well identifying the board range of functions that it serves
other than the exchange of O2/CO2 ( gases).
At the completion of this concept, you will be able to describe the:
Major functions of the respiratory system.
Processes associated with the respiratory system (i.e., ventilation,
pulmonary gas exchange [gas exchange between alveoli and blood],
transport of gases in blood, tissue gas exchange [gas
exchange between blood and body tissues]).
Respiration
Respiration can be defined as the process of supplying the body with
oxygen while removing carbon dioxide, and it consists of the following
steps:
Pulmonary Ventilation, which is also known as breathing, is the
first step in the process. Ventilation involves inhalation and
exhalation, whereby there is an exchange of O2 and CO2 between
the lungs and the atmosphere. During inhalation O2 rich and CO2
poor air is moved into the lungs, while in exhalation O2 poor and
CO2 rich air removed from the lungs.
Pulmonary Respiration, also known as external respiration, is the
exchange of gases between the alveoli of the lungs and the blood in
, the pulmonary capillaries across the respiratory membrane. Here,
CO2 diffuses from the capillary blood into the lungs, while oxygen
diffuses from the lungs and into the capillary blood.
Tissue Respiration, also known as internal respiration, is the
exchange of O2/CO2 between the blood in the systemic capillaries the
body cells. In this step, CO2 is moved from the cells to the blood,
while O2 is moved from the blood capillaries and into the cells to be
consumed in cellular respiration.
Recall the formula of cellular respiration from your discussion in A&P I
where we learnt that O2 is consumed in the following metabolic reaction of
glucose to produce ATP and CO2, hence the term cellular respiration.
C6H12O6+ 6O2 → 6CO2 +6H20 +ATP
Our body cells constantly require energy in order to function and, as
indicated by the formula shown above, ATP is efficiently produced in a
process known as aerobic cellular respiration by catabolizing organic
compounds (primarily glucose) in the presence of oxygen . This process
occurs in the cell’s power house, also known as the mitochondria
producing CO2 as a waste product which must be excreted by the
respiratory system, otherwise it can cause a disruption in the homeostatic
balance.
, Functions of the Respiratory System
As previously mentioned, the respiratory system supplies the body
with O2 and expels CO2 that is being generated as a product of
metabolism, but aside from the primary function of gas exchange, it also
serves many other functions including:
1. Communication: Involved in speech, vocalization, crying
and laughing.
2. Olfaction: Site for smelling
3. pH balance: This is achieved through the control of the levels of
CO2. When CO2 dissolves in water it will react to create
Carbonic Acid which will in turn affect the blood pH. Recall from
previous topics that the blood pH must remain in a range of 7.35-
7.45.
4. Blood Pressure regulation: Lungs are responsible for producing ACE
which is involved in the production of Angiotensin II, a strong
hormone which assists in blood pressure regulation and promotes
the release of Aldosterone.
5. Removal of abdominal contents: Breathing and muscle contractions
assists in the removal of abdominal contents as well as other
processes such as childbirth, defecation, and micturition.
6. Filtration of Blood: The lungs are capable of filtering small blood
clots in the blood.
7. Production of Platelets: Over 50% of the body’s platelets are
generated from the megakaryocytes in the lungs and not the
bone marrow.
8. Promoting blood and lymph flow: Breathing and muscle
contractions helps to promote the movement of blood and lymph in
the body.
It is important to point out that the respiratory system and circulatory
system function together to allow for the efficient exchange of O2/CO2 and
the ultimate delivery of O2 and removal of CO2 from the body tissues.
(EDAPT WEEK 6)
Anatomy & Physiology III course with a lab
,General Functions of the Respiratory System
Introduction
Let’s start off our discussion of the respiratory system with a simple
question of : What is respiration? Can we simply define it as just
breathing? The answer is going to be no, as respiration is a multi-
step process that begins with breathing in humans. Essentially respiration
is a life process that allows for the ultimate use of oxygen in cellular
metabolism and in this module we will begin our discussion of the
respiratory system by describing those processes associated with
respiration as well identifying the board range of functions that it serves
other than the exchange of O2/CO2 ( gases).
At the completion of this concept, you will be able to describe the:
Major functions of the respiratory system.
Processes associated with the respiratory system (i.e., ventilation,
pulmonary gas exchange [gas exchange between alveoli and blood],
transport of gases in blood, tissue gas exchange [gas
exchange between blood and body tissues]).
Respiration
Respiration can be defined as the process of supplying the body with
oxygen while removing carbon dioxide, and it consists of the following
steps:
Pulmonary Ventilation, which is also known as breathing, is the
first step in the process. Ventilation involves inhalation and
exhalation, whereby there is an exchange of O2 and CO2 between
the lungs and the atmosphere. During inhalation O2 rich and CO2
poor air is moved into the lungs, while in exhalation O2 poor and
CO2 rich air removed from the lungs.
Pulmonary Respiration, also known as external respiration, is the
exchange of gases between the alveoli of the lungs and the blood in
, the pulmonary capillaries across the respiratory membrane. Here,
CO2 diffuses from the capillary blood into the lungs, while oxygen
diffuses from the lungs and into the capillary blood.
Tissue Respiration, also known as internal respiration, is the
exchange of O2/CO2 between the blood in the systemic capillaries the
body cells. In this step, CO2 is moved from the cells to the blood,
while O2 is moved from the blood capillaries and into the cells to be
consumed in cellular respiration.
Recall the formula of cellular respiration from your discussion in A&P I
where we learnt that O2 is consumed in the following metabolic reaction of
glucose to produce ATP and CO2, hence the term cellular respiration.
C6H12O6+ 6O2 → 6CO2 +6H20 +ATP
Our body cells constantly require energy in order to function and, as
indicated by the formula shown above, ATP is efficiently produced in a
process known as aerobic cellular respiration by catabolizing organic
compounds (primarily glucose) in the presence of oxygen . This process
occurs in the cell’s power house, also known as the mitochondria
producing CO2 as a waste product which must be excreted by the
respiratory system, otherwise it can cause a disruption in the homeostatic
balance.
, Functions of the Respiratory System
As previously mentioned, the respiratory system supplies the body
with O2 and expels CO2 that is being generated as a product of
metabolism, but aside from the primary function of gas exchange, it also
serves many other functions including:
1. Communication: Involved in speech, vocalization, crying
and laughing.
2. Olfaction: Site for smelling
3. pH balance: This is achieved through the control of the levels of
CO2. When CO2 dissolves in water it will react to create
Carbonic Acid which will in turn affect the blood pH. Recall from
previous topics that the blood pH must remain in a range of 7.35-
7.45.
4. Blood Pressure regulation: Lungs are responsible for producing ACE
which is involved in the production of Angiotensin II, a strong
hormone which assists in blood pressure regulation and promotes
the release of Aldosterone.
5. Removal of abdominal contents: Breathing and muscle contractions
assists in the removal of abdominal contents as well as other
processes such as childbirth, defecation, and micturition.
6. Filtration of Blood: The lungs are capable of filtering small blood
clots in the blood.
7. Production of Platelets: Over 50% of the body’s platelets are
generated from the megakaryocytes in the lungs and not the
bone marrow.
8. Promoting blood and lymph flow: Breathing and muscle
contractions helps to promote the movement of blood and lymph in
the body.
It is important to point out that the respiratory system and circulatory
system function together to allow for the efficient exchange of O2/CO2 and
the ultimate delivery of O2 and removal of CO2 from the body tissues.
