Download Cardiovascular System - CK

Cardiovascular System
Say Thanks to the Authors
Click http://www.ck12.org/saythanks
(No sign in required)
To access a customizable version of this book, as well as other
interactive content, visit www.ck12.org
CK-12 Foundation is a non-profit organization with a mission to
reduce the cost of textbook materials for the K-12 market both
in the U.S. and worldwide. Using an open-content, web-based
collaborative model termed the FlexBook®, CK-12 intends to
pioneer the generation and distribution of high-quality educational
content that will serve both as core text as well as provide an
adaptive environment for learning, powered through the FlexBook
Platform®.
Copyright © 2013 CK-12 Foundation, www.ck12.org
The names “CK-12” and “CK12” and associated logos and the
terms “FlexBook®” and “FlexBook Platform®” (collectively
“CK-12 Marks”) are trademarks and service marks of CK-12
Foundation and are protected by federal, state, and international
laws.
Any form of reproduction of this book in any format or medium,
in whole or in sections must include the referral attribution link
http://www.ck12.org/saythanks (placed in a visible location) in
addition to the following terms.
Except as otherwise noted, all CK-12 Content (including
CK-12 Curriculum Material) is made available to Users
in accordance with the Creative Commons Attribution/NonCommercial/Share Alike 3.0 Unported (CC BY-NC-SA) License
(http://creativecommons.org/licenses/by-nc-sa/3.0/), as amended
and updated by Creative Commons from time to time (the “CC
License”), which is incorporated herein by this reference.
Complete terms can be found at http://www.ck12.org/terms.
Printed: April 30, 2013
www.ck12.org
C ONCEPT
Concept 1. Cardiovascular System
1
Cardiovascular System
• Describe the functions of the cardiovascular system.
What do you do for "cardio"?
"Cardio" has become slang for exercise that raises your heart rate. Cardio can include biking, running, or swimming.
Can you guess one of the main organs of the cardiovascular system? Yes, your heart.
Functions of the Cardiovascular System
Your cardiovascular system has many jobs. At times the cardiovascular system can work like a pump, a heating
system, or even a postal carrier. To do these tasks, your cardiovascular system works with other organ systems, such
as the respiratory, endocrine, and nervous systems.
The cardiovascular system (Figure 1.1) is made up of the heart, the blood vessels, and the blood. It moves nutrients,
gases (like oxygen), and wastes to and from your cells. Every cell in your body depends on your cardiovascular
system. If your cells don’t receive nutrients, they cannot survive. The main function of the cardiovascular system
is to deliver oxygen to each of your cells. Blood receives oxygen in your lungs and then is pumped, by your heart,
throughout your body. The oxygen then diffuses into your cells, and carbon dioxide, a waste product of cellular
respiration, moves from your cells into your blood to be delivered back to your lungs and exhaled. Each cell in your
body needs oxygen, as oxygen is used in cellular respiration to produce energy in the form of ATP.
The cardiovascular system also plays a role in maintaining body temperature. It helps to keep you warm by moving
warm blood around your body. Your blood vessels also control your body temperature to keep you from getting too
hot or too cold. When your brain senses that your body temperature is increasing, it sends messages to the blood
vessels in the skin to increase in diameter. Increasing the diameter of the blood vessels increases the amount of blood
and heat that moves near the skin’s surface. The heat is then released from the skin. This helps you cool down. What
do you think your blood vessels do when your body temperature is decreasing?
The blood also carries hormones, which are chemical messengers, through your body.
1
www.ck12.org
FIGURE 1.1
The cardiovascular system moves nutrients and other substances throughout the
body.
Vocabulary
• cardiovascular system: Organs involved in circulating blood and lymph through the body, including the
heart, blood vessels, and the blood.
Summary
• The cardiovascular system is made up of the heart, the blood vessels, and the blood.
• The cardiovascular system moves nutrients, hormones, gases, and wastes to and from your cells.
Practice
Use the resource below to answer the questions that follow.
• Intro To The Cardiovascular System at http://www.youtube.com/watch?v=DAXa4eR1s0M (4:04)
2
www.ck12.org
Concept 1. Cardiovascular System
MEDIA
Click image to the left for more content.
1. Where does blood enter the heart? Where does it exit the heart?
2. How does blood entering the right side of the heart differ from blood entering the left side of the heart?
3. Why is it important for the heart to have one way valves? How do you think a leaky valve affects the
functioning of the heart?
4. What are coronary arteries? What are their function? How are they involved in heart disease?
Review
1. List two components of the cardiovascular system.
2. List two functions of the cardiovascular system.
References
1. Mariana Ruiz Villarreal (LadyofHats). . Public Domain
3