The Circulatory System
Lesson 1:
Overview of the Circulatory System
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Upon completion of this lesson, students
should be able to …
Identify the organs that make up the
circulatory system.
Identify the structures that make up the heart
and briefly explain the function of each.
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Explain the conduction system of the heart.
Explain the functions of the arteries, veins,
and capillaries.
Identify the organs of the lymphatic system,
their location in the body, and the function of
each.
Describe lymph and explain how it is
circulated throughout the body.
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Show Discovery DVD
 The Beast Within
Cardiovascular system (CV)
 Consists of several components:
 Heart
 Blood
 Blood vessels
 Lymphatic system
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Pumping blood
through blood vessels
to the entire body
Provides oxygenated
blood and removes
waste
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Carries blood to the lungs
gets oxygen and releases carbon dioxide
carries the oxygenated blood to cells
The cells give up waste products to the blood
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transports substances to and from the CV
system
Is part of the immune system
1.
What are some of the problems that might
cause trouble in the cardiovascular system?
Be specific.
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http://www.neok12.com/php/watch.php?v=z
X7a08025104407275797477&t=CirculatorySystem
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Muscular pump
cardiac muscle fibers
4 chambers
Beats an average of 60 – 100 beats a minute
(bpm)
Each time the heart contracts, blood is ejected,
& pushed through the body in blood vessels
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Located to the left of the mediastinum
About the size of a fist
Shaped like an upside-down pear
Tip of the heart is called the apex
Sternum is located directly in front of the
heart
 Endocardium
 Myocardium
 Pericardium
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Inner layer
Lines the heart chambers
Smooth, thin layer
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Thick muscular middle layer
Contraction
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Outer layer
Fluid between the 2 layers of the sac reduces
friction as the heart beats
1.
What is meant by endocarditis, myocarditis,
and pericarditis?
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Coloring page inner heart anatomy
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Divided into 4 chambers
 2 atria (upper chambers)
 2 ventricles (lower chambers)
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These are divided into right and left sides by
walls – the interatrial and interventricular
septum
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http://www.neok12.com/php/watch.php?v=z
X760b6c717d557e72515c02&t=CirculatorySystem
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Cardiac circulation
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4 valves:
control the direction of blood flow
From chamber to chamber
From lungs to heart
To aorta
An atrioventricular valve
controls the
opening between
the right atrium
and right ventricle
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right ventricle and
pulmonary artery
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Allows blood to flow
from the right
ventricle into the
pulmonary artery
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Aka bicuspid valve
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Blood flows from
left atria to the left
ventricle
 Blood leaves the
left ventricle
enters the aorta
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Inferior and superior vena cava – take blood
from the body back to the heart
Pulmonary arteries – take blood from the
heart to the lungs
Pulmonary veins – take blood from the lungs
to the heart
Aorta – takes blood from the heart to the
body
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Netter’s Color Page External Heart
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Watch This First one
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Cardiologist
Hematologist
Vascular Surgeon
1.
What happens when the coronary arteries
get blocked?
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http://www.neok12.com/php/watch.php?v=z
X06707e06626a48527c7145&t=CirculatorySystem
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Path of a red blood cell
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Arteries carry blood away from the heart
 Arterioles: smaller arteries that connect to capillaries
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Veins – carry blood back to the heart
 Venules: smaller veins that connect to capillaries
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Capillaries – connecting the arteries and veins
 O2 and CO2 exchange
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thin walls that contain valves
Valves force blood to flow toward the heart
Pressure lower than in arteries
More superficial than arteries
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Lymph nodes
 Lymphatic vessels
 Thymus gland
 Spleen
 Tonsils
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Fx:
1. Remove
impurities
2. Manufacture
lymphocytes
3. Produce
antibodies
Axillary
Become enlarged during infections of
arms and breasts.
Cervical
Drain parts of head and neck.
Inguinal
Drain area of the legs and lower pelvis.
Mediastinal
Assist in draining infection from within
the chest cavity.
 Act as filters to
protect the
body
Tonsils are often removed
when infected.
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LUQ of the abdomen
In baby – produces new red blood cells
In adults – filters out and destroys old red
blood cells and recycles the iron