The Cardiovascular and
Lymphatic Systems (1:10)
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The cardiovascular system moves
blood through the body, while the
lymphatic system circulates lymph
throughout the body.
plasma
hemoglobin
platelets
capillaries
lymph
pathogen
blood pressure
Why the Blood Circulates
The cardiovascular system provides
nutrients and oxygen, carries away wastes,
and helps fight disease.
Your heart pumps blood to your body’s cells 24
hours a day, even when you’re asleep.
Why the Blood Circulates
Your heart accomplishes these important tasks:
Carrying oxygen from the lungs to body cells
Absorbing nutrients from food and delivering nutrients to body cells
Carrying carbon dioxide from your cells back to your lungs to be exhaled
Delivering other waste products to the kidneys for removal from the body
Helping the white blood cells fight disease by attacking infectious organisms
How the Blood Circulates
The cardiovascular system consists of the
heart, blood, and blood vessels.
Your heart is the muscle that makes the
cardiovascular system work.
The Heart
Inside the heart are four chambers separated by a
wall of tissue called the septum.
The two top chambers are called the atria.
The two lower chambers are called ventricles.
The Heart
Valves between the atria and ventricles allow blood
to flow through the chambers.
At the top of the right atrium is an area of muscle
that acts as a pacemaker for the heart.
The Heart
How Blood Circulates
Pulmonary circulation is the process by which
blood moves between the heart and the lungs.
Blood that has lost oxygen and picked up carbon
dioxide and wastes receives fresh oxygen in the
lungs.
Blood
Blood is the fluid that delivers oxygen, hormones,
and nutrients to the cells and carries away wastes.
Blood
Components of Blood
Plasma
Red
Blood
Cells
White
Blood
Cells
Platelets
Blood
About 55 percent of total blood volume consists of
plasma, which is mainly water, but it also contains
nutrients, proteins, salts, and hormones.
Plasma
The fluid in which other
parts of the blood are
suspended
Blood
Red blood cells make up about 40 percent of
normal blood. They contain hemoglobin.
Hemoglobin
The oxygen-carrying
protein in blood
Blood
Hemoglobin contains iron that binds with oxygen in
the lungs and releases the oxygen in the tissues.
Hemoglobin also combines with carbon dioxide, a
waste gas that is carried from the cells to the lungs
to be exhaled.
Blood
Surrounding and ingesting the
organisms that cause disease
White blood cells
have one of three
purposes:
Forming antibodies that provide
immunity against a second
attack from that specific disease
Fighting allergic reactions
Blood
When the wall of a blood vessel tears, platelets
collect at the tear and form a clot that blocks the
flow of blood.
Platelets
Types of cells in the
blood that cause blood
clots to form
Blood
Millions of each type
of blood cell can be
found in just 1
millimeter of blood.
Blood
Humans have one of four types of blood.
A
B
AB
O
(contains
antigens)
(contains
antigens)
(contains
antigens)
(does not contain
antigens)
Blood
A person with blood types A, B, or AB must receive
blood from someone with the same blood type due
to the antigens or from someone with type O blood
because it has no antigens.
Blood
People with type O blood are called universal
donors, because anyone can receive their blood.
Blood Vessels
Arteries
The Three
Main Types of
Blood Vessels
Capillaries
Veins
Blood Vessels
Arteries are vessels that branch into progressively
smaller vessels called arterioles, which deliver
blood to capillaries.
Arteries
Blood vessels that carry
oxygenated blood away from
the heart
Blood Vessels
Capillaries reach almost all body cells. Capillaries
near the skin’s surface can dilate or constrict to
adjust body temperature.
Capillaries
Small vessels that carry blood
from arterioles and to small
vessels called venules, which
empty into veins
Blood Vessels
The large veins, the vena cava, carry
deoxygenated blood to the right atrium. Pulmonary
veins carry oxygenated blood to the left atrium.
Veins
Blood vessels that return
blood to the heart
How Lymph Circulation Works
The lymphatic system helps fight infection
and provides immunity to disease.
The lymphatic system is a system of vessels
much like the cardiovascular system.
How Lymph Circulation Works
The lymphatic system consists of a network of
vessels and tissues that move and filter lymph.
Lymph
The clear fluid that fills the
spaces around body cells
How Lymph Circulation Works
Lymph contains water, proteins, fats, and
specialized white blood cells called lymphocytes
that protect the body against pathogens.
Pathogen
A microorganism that
causes disease
How Lymph Circulation Works
Lymph is filtered by lymph nodes, small beanshaped organs found in lymph vessels.
White blood cells within lymph nodes trap and
destroy pathogens.
Maintaining Your Circulatory Health
Healthy habits can help protect the health of
the cardiovascular and lymphatic systems.
Many problems with the cardiovascular and
lymphatic systems first appear later in life.
Maintaining Your Circulatory Health
Maintaining Your Circulatory Health
Eat a well-balanced diet.
Maintain a healthy weight.
Participate in regular aerobic exercise for at least 30 minutes three or
four times per week.
Avoid secondhand smoke and using tobacco products.
Avoid illegal drug use.
Get regular medical checkups.
Blood Pressure
Maintaining blood pressure in the cardiovascular
system is important for proper blood circulation.
Blood pressure
A measure of the amount of force that the
blood places on the walls of blood vessels,
particularly large arteries, as it is pumped
through the body
Blood Pressure
Systolic pressure
The maximum pressure as your
heart contracts to push blood
into your arteries.
A blood pressure
reading includes
two numbers.
Diastolic pressure
The pressure at its lowest point
when your ventricles relax.
Blood Pressure
A healthy person’s blood pressure will vary within a
normal range of below 120/80.
Blood pressure that is above 140/90 is considered
high and places a strain on the heart.
Cardiovascular System Problems
Some cardiovascular problems are inherited;
others result from illness, diet, or aging.
Disorders of the cardiovascular system have
wide-ranging effects and varying treatments.
Cardiovascular System Problems
Congenital heart defects
Conditions of the heart that are present at birth.
Heart murmurs
Abnormal sounds that are made as blood flows
through the heart.
Varicose veins
Formed as result of the valves in veins not closing
tightly enough to prevent backflow of blood.
Anemia
A condition in which the ability of the blood to carry
oxygen is reduced.
Hemophilia
An inherited disorder. The blood does not clot
properly.
Leukemia
A form of cancer in which any one of the different
types of white blood cells is produced excessively
and abnormally.
Lymphatic System Problems
Problems of the lymphatic system can range
from mild to life-threatening.
Disorders of the lymphatic system may be
caused by infection or heredity.
Lymphatic System Problems
Tonsillitis
Your tonsils help reduce the number of pathogens
entering the body through the respiratory system.
If the tonsils become infected, tonsillitis results.
Immune
deficiency
Immune deficiency results if the immune system is
weakened and can no longer protect the body
against infection.
Hodgkin’s
disease
Also called Hodgkin’s lymphoma, this type of
cancer affects the lymph tissue in lymph nodes and
the spleen.
After You Read
Reviewing Facts and Vocabulary
1. Why is the cardiovascular system
important to your overall health?
This system carries oxygen and nutrients to
cells, carries carbon dioxide and wastes
away from cells, and fights disease through
blood cells that fight infection.
After You Read
Reviewing Facts and Vocabulary
2. What behaviors will help you prevent
high blood pressure?
Maintain a healthy weight with a nutritious,
low-salt diet; stay physically active;
manage stress; avoid tobacco and drugs.
After You Read
Reviewing Facts and Vocabulary
3. What do the blood pressure numbers
measure?
The top number measures the maximum
pressure as your heart contracts to push
blood into your arteries. The bottom number
measures the pressure at its lowest point
when your ventricles relax.