Transcript Lab07RespirationAndCirculation

Principles of Biology
By
Frank H. Osborne, Ph. D.
Lab 7 - Respiration and Circulation
Types of Respiration
A. Cellular respiration
1. A cell of the body removes oxygen (O2) from
the blood which is part of the circulatory system.
2. The cell uses the O2 to oxidize glucose to
produce energy (ATP) and carbon dioxide (CO2).
3. The CO2 leaves the cell and enters the blood.
B. External respiration
1. Inspiration
a. The diaphragm contracts and the chest wall
expands to produce a partial vacuum in the lungs.
b. Air enters the lungs because of the lower
pressure.
c. The air that enters the lungs has a high
concentration of O2 and a low concentration of
CO2 and H2O.
B. External respiration
2. Expiration
a. The diaphragm relaxes and the chest wall
contracts to produce a pressure in the lungs.
b. Air leaves the lungs because of the higher
pressure.
c. The air that enters the lungs has a high
concentration of CO2 and H2O and a low
concentration of O2.
How a
Human
Breathes
Control of Respiration
A. The diaphragm
1. The diaphragm is a muscle composed of
smooth muscle cells.
2. The breathing cycle (one inhalation, one
exhalation) occurs approximately 16 times per
minute.
3. There is some voluntary control over the
diaphragm.
Control of Respiration
B. The nervous system
1. There is a CO2 sensor located in the brain
stem.
2. When the concentration of CO2 increases,
the autonomic nervous system causes the
diaphragm to speed up.
Control of Respiration
a. Holding the breath increases CO2
concentration in the blood.
i. After holding the breath, the breathing rate
is faster.
ii. Holding the breath deprives the heart and
brain of oxygen and could cause permanent
damage. Do not do it.
Control of Respiration
b. Exercise increases the concentration of CO2
in the blood.
i. During exercise, the autonomic nervous
system speeds up the breathing rate.
ii. After exercise, the concentration of CO2
lowers and the autonomic nervous system slows
the breathing rate.
Control of
Respiration
Circulation of the Blood
A. The heart
1. The heart pumps the blood.
2. The right side of the heart collects the blood
returning from the body and pumps it to the
lungs.
3. The left side of the heart collects the blood
returning from the lungs and pumps it to the
body.
Heart:
External
Heart:
Section
Circulation of the Blood
B. The arteries
1. The arteries carry blood away from the
heart to the body or the lungs.
2. The contraction of the heart causes the
arteries to contract using rings of smooth muscle.
3. The pulse is the contraction of the arteries.
B. The veins
1. The veins carry blood to the heart from the
body or the lungs.
2. Veins do not have muscles.
a. Blood is pushed in the veins by the
motion of the body.
b. Veins have valves to prevent the blood
from flowing backward.
c. Veins do not pulsate because they do not
have smooth muscles that contract.
Gas exchange
in the body
Types of Circulation
1. The pulmonary circulation
a. The blood returns from the body to the
right atrium of the heart. This blood is high in
CO2 and low in O2.
b. The right atrium pumps the blood into
the right ventricle.
Types of Circulation
c. The right ventricle pumps the blood to the
lungs through the pulmonary arteries.
d. The blood returns from the lungs through
the pulmonary veins. This blood is high in O2
and low in CO2.
2. The systemic circulation
a. The blood returns from the lungs to the left
atrium of the heart.
b. The left atrium pumps the blood to the left
ventricle.
c. The left ventricle pumps the blood to the
body through the aorta.
d. The blood returns from the body through
the inferior and superior venae cavae.
Interrelationship Between
Respiration and Circulation
A. The respiratory system
1. Oxygen from the air enters the alveoli of
the lungs.
2. The O2 diffuses across the moist cell
membranes into the capillaries of the
circulatory system.
Interrelationship Between
Respiration and Circulation
3. The CO2 and some H2O in the blood
diffuse from the circulatory system, across the
moist cell membranes, into the alveoli.
4. The CO2 and H2O leave the body and go
into the air.
Interrelationship Between
Respiration and Circulation
B. The circulatory system
1. Blood high in O2 leaves the lungs and goes
to the heart.
2. The heart pumps the blood to the cells of
the body.
Interrelationship Between
Respiration and Circulation
3. The O2 diffuses from the capillaries,
across the moist cell membranes, into the cells
of the body.
4. The CO2 and H2O from cellular
respiration diffuse from the cells of the body,
across the moist cell membranes, into the
capillaries.
Transport of Respiratory Gases
1. The circulatory system carries respiratory
gases to and from the lungs.
2. The respiratory system exchanges
respiratory gases with the air.
The End
Lab 7
Respiration and Circulation