Chapter 6 Test Study Guide: The
Circulatory System
Chambers
The atria are receiving chambers and the ventricles are pumping or
delivering chambers
Layers of the Heart
Epicardium
- Location: the outer layer of the heart
- Description: thin, serous (watery) membrane that is continuous with
the lining of the pericardium
- Function: covers the heart and attaches to the pericardium
Myocardium
- Location: middle layer of the heart
- Description: a thick layer of cardiac muscle
- Function: contracts to pump blood into the arteries
Endocardium
- Location: inner layer of the heart
- Description: think layer of epithelial cells that is continuous with the
lining of the blood vessels
- Function: lines the interior chambers and valves
Chambers of the Heart
Right atrium
- Location: upper right chamber
- Function: receives deoxygenated blood from the body via both the
superior vena cava and the inferior vena cava and pumps it into the
right ventricle
Left ventricle
- Location: lower left chamber
- Function: receives blood from the left atrium and pumps it into the
aorta, the walls of the left ventricle are nearly 3 times as thick as
those of the right ventricle owing to the force required to pump the
blood into the arterial system
Heart Function
The contracting phase of the cardiac cycle is called systole
The relaxing phase is called diastole
, Electrocardiogram
Is a graphic record of the heart’s electrical activity during the cardiac
cycle
Heart Rate and Cardiac Output
An irregularity in the heart rate, rhythm, or beat is called arrhythmia
A slow rate, less than 60 bpm is called bradycardia
A fast heart rate over 100 bpm is called tachycardia
Blood Pressure
Is the force (pressure) or tension exerted by the blood on the walls of
blood vessels
Systolic pressure: the arterial pressure during contraction of the
ventricles
Diastolic pressure: the arterial pressure during relaxation of the
ventricles
The Vascular System Structures
It has been estimated that the human vascular system has around
60,000 miles of blood vessels
Arteries
Are blood vessels that carry blood away from the heart
The smallest branches of arteries that join with the capillaries are
called arterioles
Key Point
The pulmonary veins are the only veins that carry oxygenated blood
They are part of the pulmonary circulation and carry oxygenated blood
from the lungs back to the heart
They are classified as veins because they return blood to the heart
Veins
The smallest veins are called venules
Capillaries
Circulatory System
Chambers
The atria are receiving chambers and the ventricles are pumping or
delivering chambers
Layers of the Heart
Epicardium
- Location: the outer layer of the heart
- Description: thin, serous (watery) membrane that is continuous with
the lining of the pericardium
- Function: covers the heart and attaches to the pericardium
Myocardium
- Location: middle layer of the heart
- Description: a thick layer of cardiac muscle
- Function: contracts to pump blood into the arteries
Endocardium
- Location: inner layer of the heart
- Description: think layer of epithelial cells that is continuous with the
lining of the blood vessels
- Function: lines the interior chambers and valves
Chambers of the Heart
Right atrium
- Location: upper right chamber
- Function: receives deoxygenated blood from the body via both the
superior vena cava and the inferior vena cava and pumps it into the
right ventricle
Left ventricle
- Location: lower left chamber
- Function: receives blood from the left atrium and pumps it into the
aorta, the walls of the left ventricle are nearly 3 times as thick as
those of the right ventricle owing to the force required to pump the
blood into the arterial system
Heart Function
The contracting phase of the cardiac cycle is called systole
The relaxing phase is called diastole
, Electrocardiogram
Is a graphic record of the heart’s electrical activity during the cardiac
cycle
Heart Rate and Cardiac Output
An irregularity in the heart rate, rhythm, or beat is called arrhythmia
A slow rate, less than 60 bpm is called bradycardia
A fast heart rate over 100 bpm is called tachycardia
Blood Pressure
Is the force (pressure) or tension exerted by the blood on the walls of
blood vessels
Systolic pressure: the arterial pressure during contraction of the
ventricles
Diastolic pressure: the arterial pressure during relaxation of the
ventricles
The Vascular System Structures
It has been estimated that the human vascular system has around
60,000 miles of blood vessels
Arteries
Are blood vessels that carry blood away from the heart
The smallest branches of arteries that join with the capillaries are
called arterioles
Key Point
The pulmonary veins are the only veins that carry oxygenated blood
They are part of the pulmonary circulation and carry oxygenated blood
from the lungs back to the heart
They are classified as veins because they return blood to the heart
Veins
The smallest veins are called venules
Capillaries
