Circulatory System
Circulatory System
• Your pigs have been doubly injected (red for
arteries, blue for veins)
• Red arteries = move blood (rich in oxygen)
“Away” from the heart
• Blue veins = move blood (low in oxygen)
back to the heart
*sometimes there’s exceptions to this rule!!!!
Pericardium
•
Pericardium- a membrane (mesentery) surrounding
the heart. Secretes a watery fluid to prevent the heart
from rubbing against surrounding organs when it
beats.
• In living animals, the
pericardial cavity is filled
with fluid that acts as a
shock absorber to
protect the heart
from injury
Coronary artery and Coronary
vein
• The coronary artery and coronary vein lie
in the diagonal groove between the 2
ventricles.
• These vessels supply and drain the heart
(the heart is a muscle and as such has the
same requirements of any other organ).
• When the coronary artery becomes
obstructed, a heart attack may occur. It is
the coronary arteries that are "bypassed"
in coronary bypass surgery.
•
•
Coronary Vein- blue blood vessel
located on the front (ventral) surface of
the heart. (May not be injected in all
pigs.) Drains the heart muscle tissue of
blood and moves it back into the right
atrium.
Coronary Artery- red blood vessel
located on the front (ventral) surface of
the heart. (May not be injected in all
pigs) Brings blood from the aorta and
supplies the heart muscle tissue with
food and oxygen.
How blood flows
• In an adult mammal deoxygenated blood
(low in O2)flows into the right atrium from
the anterior and posterior vena cava.
• It then makes the following circuit: right
ventricle, pulmonary trunk, pulmonary
artery, lungs, pulmonary vein, left atrium,
left ventricle, aortic arch, aorta, and on into
the systemic circulation.
Blood pathway
How blood flows
•
•
•
•
•
•
Right Atrium- Collects blood low in oxygen
and filled with food from the body and pumps it
into the right ventricle.
Right Ventricle- Collects blood from the right
atrium and pumps it to the lungs.
Pulmonary Trunk- takes blood from the right
ventricle to the lungs.
Pulmonary Vein- returns oxygenated blood
from lungs to the left atrium
Left Atrium- Collects blood from the lungs
rich in oxygen and food and pumps it to the left
ventricle.
Left Ventricle- Collects blood from the left
atrium and pumps it throughout the body.
Aorta and Vena Cava
•
•
•
Aortic Arch- behind the pulmonary trunk and
forming an arch leading toward the lower part
of the body. Carries blood rich in food and
oxygen from the left ventricle to all parts of the
body.
Dorsal Aorta- continuation of the aorta along
the dorsal body wall behind the lungs, liver,
and small intestine. Carries blood rich in food
and oxygen to the lower body organs and to
the legs.
Posterior Vena Cava- Brings blood through
the umbilical cord low in oxygen and rich in
carbon dioxide form the lower body to the
right atrium.
Flow of blood through the heart
Model of human heart