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Human Anatomy - Learning Module #4
The Cardio-Pulmonary-Vascular System
Part C
Part C: The Vascular System
Learning Objectives
The vascular system involves all the blood vessels that transport blood throughout the body and provide the physical site where gases, nutrients, and other substances are exchanged with body cells. When blood vessels do not function properly, blood constituents do not circulate effectively throughout the body. As a result, tissue injury occurs, metabolism is impaired, and the functions of every bodily system are threatened.
Types of Blood Vessels
Blood vessels are tubular structures. There are 5 different basic types of blood vessels:
Learning Objectives
- Describe the differences between the different types of blood vessels
- Name and locate the major blood vessels of the peripheral vascular system
- Understand the role of the vascular system in homeostasis
The vascular system involves all the blood vessels that transport blood throughout the body and provide the physical site where gases, nutrients, and other substances are exchanged with body cells. When blood vessels do not function properly, blood constituents do not circulate effectively throughout the body. As a result, tissue injury occurs, metabolism is impaired, and the functions of every bodily system are threatened.
Types of Blood Vessels
Blood vessels are tubular structures. There are 5 different basic types of blood vessels:
- Arteries – large, thick vessels carrying oxygenated blood away from the heart
- Arterioles – small, thick vessels carrying oxygenated blood away from the heart
- Capillaries – tiny, very thin vessels involved in gas exchange
- Venules - small, thin vessels carrying de-oxygenated blood to the heart
- Veins - large, thin vessels carrying de-oxygenated blood to the heart
These different types of blood vessels vary slightly in their structures, but they share the same general features. Arteries and arterioles have thicker walls than veins and venules because they receive the blood under higher pressure made by the pumping of the heart. The arteries and arterioles need thicker walls, which are made of smooth muscle under control of the autonomic (involuntary) nervous system, to regulate blood pressure and maintain blood flow.
Blood flows through the hollow passageway made by the tubular arteries and veins. This hollow passageway is called the lumen. Arteries have smaller lumens than veins to help maintain higher pressures for pushing the blood further downstream.
The thicker walls and smaller lumens of arteries make them more rounded in appearance in cross section than the walls and lumens of veins, which usually appear irregular and are often collapsed.
Blood flows through the hollow passageway made by the tubular arteries and veins. This hollow passageway is called the lumen. Arteries have smaller lumens than veins to help maintain higher pressures for pushing the blood further downstream.
The thicker walls and smaller lumens of arteries make them more rounded in appearance in cross section than the walls and lumens of veins, which usually appear irregular and are often collapsed.
Major Blood Vessels of the Peripheral Vascular System
Arterial System
The heart pumps all the blood into the peripheral vascular system by contracting the left ventricle and ejecting the blood into the aorta, which is the thickest (most muscular) blood vessel and has the largest lumen. All the major parts and organs of the body are supplied with oxygenated blood by arteries that branch directly off the Aorta.
Ascending Aorta
Arterial System
The heart pumps all the blood into the peripheral vascular system by contracting the left ventricle and ejecting the blood into the aorta, which is the thickest (most muscular) blood vessel and has the largest lumen. All the major parts and organs of the body are supplied with oxygenated blood by arteries that branch directly off the Aorta.
Ascending Aorta
- Right & Left Coronary Arteries to supply the heart
- Brachio-Cephalic Artery (right arm-head artery) branches into the:
- Right Subclavian Artery to supply the right arm
- Right Common Carotid Artery to supply the right side of the head
- Left Common Carotid Artery to supply the left side of the head
- Left Subclavian Artery to supply the left arm
Vasculature of the Head
The Common Carotid Arteries supplying the head branch into the Internal Carotid Artery to supply the brain and the External Carotid Artery to supply the face and scalp.
The Vertebral Arteries branch off the Subclavian Arteries at the base of the neck to supply the cervical vertebrae and the muscles of the neck.
The Common Carotid Arteries supplying the head branch into the Internal Carotid Artery to supply the brain and the External Carotid Artery to supply the face and scalp.
The Vertebral Arteries branch off the Subclavian Arteries at the base of the neck to supply the cervical vertebrae and the muscles of the neck.
Vaculature of the Upper Limb
The Subclavian Artery supplying the upper limb becomes the Axillary Artery in the shoulder region. Then the Axillary Artery becomes the Brachial Artery in the arm region. The Brachial Artery then divides into the Radial and Ulnar Arteries to supply the forearm region. These re-join as the Palmar Arches in the hand.
The Subclavian Artery supplying the upper limb becomes the Axillary Artery in the shoulder region. Then the Axillary Artery becomes the Brachial Artery in the arm region. The Brachial Artery then divides into the Radial and Ulnar Arteries to supply the forearm region. These re-join as the Palmar Arches in the hand.
Vasculature of the Trunk
Descending (Thoracic) Aorta
Abdominal Aorta
Descending (Thoracic) Aorta
- Eleven pairs of Right & Left Posterior Intercostal Arteries branch to supply the chest wall by coursing between the ribs.
- Passes through the diaphragm to enter the abdomen.
Abdominal Aorta
- Right & Left Renal Arteries to supply (and be filtered by) the kidneys. 20% of cardiac output (CO) is directed to the kidneys for filtration and to regulate blood volume and pressure) by urine. Adequate water consumption is vital for kidney function.
- The Celiac Trunk and the Superior & Inferior Mesenteric Arteries to supply the Gastro-Intestinal System, including the stomach, small and large intestines, liver, and pancreas
- Bifurcates into the Right & Left Common Iliac Arteries as it reaches the pelvic region to supply the legs.
Vasculature of the Lower Limb
The bifurcation of the Abdominal Aorta into the right and left Common Iliac Arteries supply blood to the lower limb. The Common Iliac Artery divides into the Internal Iliac Artery to supply the pelvic region and into the External Iliac, which continues as the Femoral Artery in the thigh region. The Femoral Artery becomes the Popliteal Artery (posteriorly) in the knee region and then divides into the anterior and posterior Tibial Arteries and the Fibular Artery in the lower leg region. These re-join as the Plantar Arch in the foot.
The bifurcation of the Abdominal Aorta into the right and left Common Iliac Arteries supply blood to the lower limb. The Common Iliac Artery divides into the Internal Iliac Artery to supply the pelvic region and into the External Iliac, which continues as the Femoral Artery in the thigh region. The Femoral Artery becomes the Popliteal Artery (posteriorly) in the knee region and then divides into the anterior and posterior Tibial Arteries and the Fibular Artery in the lower leg region. These re-join as the Plantar Arch in the foot.
Venous System
After the arteries have supplied the oxygenated blood to the capillary beds of all the body parts and organs, the de-oxygenated blood is collected from the capillary beds from those body parts and organs and transported back to the heart by “venous return.” In general, there is a vein that corresponds to the artery in each regional part of the body (often by the same name).
Lower Limb & Pelvis: Blood from the foot is collected by the Dorsal and Plantar Arches. Blood from the leg is collected by the anterior and posterior Tibial Veins and the Fibular Vein. Blood from the thigh is collected by the Popliteal, Femoral, and Deep Femoral Veins. The Femoral Vein becomes the External Ileac Vein in the pelvis region and is joined by the Internal Ileac Vein to become the Common Ileac Vein. The right and left Common Ileac Veins join to form the Lumbar Vein, which corresponds to the Abdominal Aorta.
Trunk: The Lumbar Vein receives the right and left Renal Veins from the kidneys and the Hepatic Vein from the Gastro-Intestinal System. The Lumbar Vein then passes through the diaphragm to become the Inferior Vena Cava, which empties directly into the Right Ventricle of the heart.
Note: The blood from the capillary beds of the digestive organs supplied by the Mesenteric Artery is collected by the Hepatic Portal Vein and delivered to the liver. After being “detoxified” in the capillary beds of the liver, the blood is collected by the Hepatic Vein, which empties into the Lumbar Vein.
Upper Limb: Blood from the hand is collected by the Palmar Arches. Blood from the forearm is collected by the Radial and Ulnar Veins. Blood from the arm is collected by the Brachial and Basilic Veins. The Basilic Vein becomes the Axillary Vein in the shoulder region and then becomes the Subclavian Vein in the upper trunk.
A prominent, superficial vein on the forearm and arm is the Cephalic Vein, which runs from the wrist to the shoulder. The Median Cubital Vein at anterior elbow connects the Cephalic vein to the deeper Basilic Vein and is the common site to draw blood for laboratory analysis.
After the arteries have supplied the oxygenated blood to the capillary beds of all the body parts and organs, the de-oxygenated blood is collected from the capillary beds from those body parts and organs and transported back to the heart by “venous return.” In general, there is a vein that corresponds to the artery in each regional part of the body (often by the same name).
Lower Limb & Pelvis: Blood from the foot is collected by the Dorsal and Plantar Arches. Blood from the leg is collected by the anterior and posterior Tibial Veins and the Fibular Vein. Blood from the thigh is collected by the Popliteal, Femoral, and Deep Femoral Veins. The Femoral Vein becomes the External Ileac Vein in the pelvis region and is joined by the Internal Ileac Vein to become the Common Ileac Vein. The right and left Common Ileac Veins join to form the Lumbar Vein, which corresponds to the Abdominal Aorta.
Trunk: The Lumbar Vein receives the right and left Renal Veins from the kidneys and the Hepatic Vein from the Gastro-Intestinal System. The Lumbar Vein then passes through the diaphragm to become the Inferior Vena Cava, which empties directly into the Right Ventricle of the heart.
Note: The blood from the capillary beds of the digestive organs supplied by the Mesenteric Artery is collected by the Hepatic Portal Vein and delivered to the liver. After being “detoxified” in the capillary beds of the liver, the blood is collected by the Hepatic Vein, which empties into the Lumbar Vein.
Upper Limb: Blood from the hand is collected by the Palmar Arches. Blood from the forearm is collected by the Radial and Ulnar Veins. Blood from the arm is collected by the Brachial and Basilic Veins. The Basilic Vein becomes the Axillary Vein in the shoulder region and then becomes the Subclavian Vein in the upper trunk.
A prominent, superficial vein on the forearm and arm is the Cephalic Vein, which runs from the wrist to the shoulder. The Median Cubital Vein at anterior elbow connects the Cephalic vein to the deeper Basilic Vein and is the common site to draw blood for laboratory analysis.
There are two prominent superficial veins in the leg and thigh. The Small Saphenous Vein in the lateral leg empties into the deeper Popliteal Vein at the knee. The Great Saphenous Vein in the medial leg and thigh empties into the deeper Femoral Vein at the groin. These superficial veins have several (8-20) valves.
The valves and walls of the Saphenous Veins can lose their integrity due to increased gravitational pressure and fail to transport the blood efficiently. This can cause the veins to become varicose (enlarged and twisted).
Although very unsightly and sometimes uncomfortable, varicose veins are not considered a serious medical condition, unless complications arise. Exercise improves muscle tone and circulation in the legs and reduces the risk of developing varicose veins, but exercise can not cure them.
Head & Neck: The blood from the face and scalp is collected by the External Jugular Vein. The blood from the anterior part of the neck is collected by the Anterior Jugular Vein. Both veins empty into the Subclavian Vein. The blood from the brain is collected by the large Internal Jugular Vein, which joins the Subclavian Vein to form the Brachiocephalic Vein. The right and left Brachiocephalic Veins join to form the Superior Vena Cava (SVC). The SVC empties directly into the Right Ventricle of the heart.
The valves and walls of the Saphenous Veins can lose their integrity due to increased gravitational pressure and fail to transport the blood efficiently. This can cause the veins to become varicose (enlarged and twisted).
Although very unsightly and sometimes uncomfortable, varicose veins are not considered a serious medical condition, unless complications arise. Exercise improves muscle tone and circulation in the legs and reduces the risk of developing varicose veins, but exercise can not cure them.
Head & Neck: The blood from the face and scalp is collected by the External Jugular Vein. The blood from the anterior part of the neck is collected by the Anterior Jugular Vein. Both veins empty into the Subclavian Vein. The blood from the brain is collected by the large Internal Jugular Vein, which joins the Subclavian Vein to form the Brachiocephalic Vein. The right and left Brachiocephalic Veins join to form the Superior Vena Cava (SVC). The SVC empties directly into the Right Ventricle of the heart.
The Role of the Vascular System
Homeostasis (hō-mē-əˈ-stā-sis), noun – The maintenance of a relatively stable equilibrium between interdependent elements of a living organism by adjusting physiological processes.
In order to maintain homeostasis and provide adequate blood flow to the different parts of the body during changes in physiological demands, such as during rest, mild-moderate exercise, or maximal strenuous activity, the cardiovascular system engages in “resource allocation.”
When exercising, more blood will be directed to skeletal muscles and the heart, lungs, and skin, and less to the other organs. Following a meal, more blood is directed to the digestive system, and less to skeletal muscles. (Thus, the recommendation to not exercise immediately after a meal.) Only the brain receives a fairly constant supply of blood whether you are exercising, studying, eating, or sleeping.
Homeostasis (hō-mē-əˈ-stā-sis), noun – The maintenance of a relatively stable equilibrium between interdependent elements of a living organism by adjusting physiological processes.
In order to maintain homeostasis and provide adequate blood flow to the different parts of the body during changes in physiological demands, such as during rest, mild-moderate exercise, or maximal strenuous activity, the cardiovascular system engages in “resource allocation.”
When exercising, more blood will be directed to skeletal muscles and the heart, lungs, and skin, and less to the other organs. Following a meal, more blood is directed to the digestive system, and less to skeletal muscles. (Thus, the recommendation to not exercise immediately after a meal.) Only the brain receives a fairly constant supply of blood whether you are exercising, studying, eating, or sleeping.
The Vascular System Inter-Connects All the Body Systems
The chart below is given to illustrate the complexity of the many interdependent systems of the human body. It does not even begin to scratch the surface of the life sciences, let alone the mysteries of our Creator God.
The roles of the vascular system detailed in this chart will not be on the Certification Exam.
The vascular system makes life possible, because the life is in the blood.
Leviticus 17:11 – For the life of the flesh is in the blood: and I have given it to you upon the altar to make an atonement for your souls: for it is the blood (the life of Christ) that maketh an atonement for the soul.
Psalm 139:14 – I will praise thee; for I am fearfully and wonderfully made: marvelous are thy works; and that my soul knoweth right well.
Isaiah 43:7 – Even every one that is called by my name: for I have created him for my glory,
I have formed him; yea, I have made him.
Psalm 139:14 – I will praise thee; for I am fearfully and wonderfully made: marvelous are thy works; and that my soul knoweth right well.
Isaiah 43:7 – Even every one that is called by my name: for I have created him for my glory,
I have formed him; yea, I have made him.
Module 4C: LAB
Name and Locate the Major Arteries of the Vascular System
and the body parts or organs that each artery supplies.
Name and Locate the Major Arteries of the Vascular System
and the body parts or organs that each artery supplies.
The Arteries & Veins to know for the Certification Exam include:
Thoracic Aorta
-- Ascending Aorta
Common Carotid Artery
Subclavian Artery
-- Descending Aorta
Abdominal Aorta
Common Ileac Artery
Superior Vena Cava
Inferior Vena Cava
Thoracic Aorta
-- Ascending Aorta
- Coronary Arteries
- Brachiocephalic Artery
- -- Right Common Carotid Artery
- -- Right Subclavian Artery
- Left Common Carotid Artery
- Left Subclavian Artery
Common Carotid Artery
- External Carotid
- Internal Carotid
Subclavian Artery
- Axillary Artery
- Brachial Artery
- Ulnar Artery
- Radial Artery
- Palmar Arches
-- Descending Aorta
- Posterior Intercostal Arteries
Abdominal Aorta
- Renal Arteries
- Celiac Trunk
- Mesenteric Arteries
- Common Ileac Arteries
Common Ileac Artery
- Internal Ileac Artery
- External Ileac Artery
- Femoral Artery
- Popliteal Artery
- Tibial Artery
- Fibular Artery
- Plantar Arch
Superior Vena Cava
- Brachiocephalic Vein
- Subclavian Vein
- Internal Jugular Vein
- -- External Jugular Vein
Inferior Vena Cava
- Lumbar Vein
- Common Ileac Vein