Transcript Cardiovascular System 1

CardiovascularObjectives:
System
1. Identify
Chapter
13 structures and
functions of the cardiovascular
system.
2. Trace the flow of blood
through the body.
Coverings of the Heart
• Pericardium: (?)
1. Visceral (?)pericardium (“epicardium”(?))
– Innermost layer
– Covers the heart
2. Parietal (?)pericardium
– Outer layer of visceral pericardium
– Forms inner lining of fibrous pericardium
3. Fibrous (?)pericardium
– Dense connective tissue attached to central portion
of diaphragm, posterior of sternum, vertebral
column, and large blood vessels attached to heart
Pericardial Cavity
• Space between parietal and visceral
pericardium layers
• Filled with serous fluid to reduce friction
between the membranes as the heart moves
Wall of the Heart
1. Epicardium
– Outer layer
– Corresponds to visceral pericardium
– Protects heart by reducing friction
2. Myocardium
– Thick, middle layer
– Consists mostly of cardiac muscle tissue that pumps
blood out of the heart chambers
3. Endocardium
– Inner layer
– Epithelium and connective tissue
Heart Chambers & Valves
• ????
• Four hollow chambers:
– Upper chambers = atria (atrium)
– Lower chambers = ventricles
• Atria
– Thin walls
– Receive blood returning to the heart
• Ventricles
– Receive blood from the atria
– Contract to force blood out of the heart into the
arteries
Heart Chambers & Valves,
continued…..
• Left atrium and ventricle are separated from the
right atrium and ventricle by a solid, wall-like
septum.
• Atrioventricular valve – separates ???
– Tricuspid valve
• on the right
• “3 cusps”
– Bicuspid valve (“mitral valve”)
• on the left
• “2 cusps”
– Allows blood to flow ONLY from atrium to ventricular
– no backflow
Heart Chambers & Valves,
continued…..
• Right atrium receives blood from:
– Superior vena cava (???)
– Inferior vena cava (???)
– Coronary sinus – small vein that drains blood
from the myocardium
• Right ventricle
– Thinner muscular wall than the left ventricle
– Only has to pump blood to the lungs
• Blood leaves the ventricle through the
pulmonary valve, and enters the pulmonary
trunk, which divides into the left and right
pulmonary arteries.
Heart Chambers & Valves,
continued…..
• Left atrium receives blood from the lungs
through 4 pulmonary veins.
• Blood leaves the left ventricle through the
aortic valve, into the aorta.
• Ventricular wall is thicker – has to pump
blood to the rest of the body
Sketch & Label the Valves
Label the Exterior Heart