Download Chapter 5

Chapter 5
Systems of the Human Body
Lesson 1 What are the skeletal and
muscular systems?
1. A group of tissues working together form
an organ. Organ carry out processes
that are needed for life.
Example: Your heart is made of muscles, nerves,
and tissues that work together to pump blood.
2. A group of organs working together forms
an organ system. If one organ in a
system is damaged, the other organs will
be affected.
Skeletal System
3. Your skeleton is made mostly of a tissue called
bone. Your body cannot stand without its
skeletal system.
4. Your skeleton protects the organs in your
body and helps you move.
5. Calcium is a mineral that helps keep your
bones strong and muscles and nerve tissues
working properly. Bones store calcium and
other mineral for your body.
6. Bones also produce different kinds of blood
cells, which fight bacteria and help stop
bleeding.
Joints
7. When one bone attaches to another
bone, it is called a joint. There are
two types of joint.
• Ball-and-socket joints – allow
circular movement (shoulders and
hips)
• Hinge joints – allow back and
forward movement or bending
(knee)
Muscular System
8. Muscles that move your body are attached to
your skeleton (skeletal muscles) and form the
muscular system.
9. You can walk, run, smile, sing, breathe, and
swallow because of your muscular system.
Types of Muscles
Voluntary Muscles – you choose when they work
and most are skeletal muscles.
•
Involuntary Muscles – You cannot control.
They help you digest food and breathe.
Lesson 2
What are the respiratory and
circulatory systems?
Lesson 2- Respiratory and
Circulatory System
1. When your body cells use oxygen, they give off
carbon dioxide, which leaves your body when
you breathe.
2. Lungs are the main organs in the respiratory
system. The diaphragm is the muscle below
the lungs that forces air in and out.
**See page 149 for pictures of the parts of the
respiratory system!
Lesson 2—Respiratory and
Circulatory System
3. Your respiratory and circulatory systems
work together to bring oxygen to cells
and carbon dioxide away from cells.
4. Oxygen passes from your lungs to your
blood to your heart.
5. The circulatory system (heart, blood
vessels, and blood) has the special job of
moving blood through the body.
Your Heart ♥
6. Both sides of your heart work as a pump
and collect blood. The right side collects
blood from the body and pumps it to your
lungs. The left side collects blood filled
with oxygen from the lungs and pumps it
to the body.
7. Each side of the heart has two
chambers, an atrium and a ventricle.
The Heart
8. The atrium receives blood.
9. The blood passes through a valve (tube)
to the ventricle.
Lesson 3
What are the digestive and
nervous systems?
Digestive System
1. Your digestive system breaks food into
nutrients that your body can use. This is
called digestion. It begins in your mouth.
** See page 153 to see the path food
takes through the body.
Central Nervous System
2. Your central nervous system is the control
center of your body. It carries signals from one
system to another.
3. This system controls breathing, heart rate, and
movements of muscles.
4. The nervous system handles information from
the sense organs.
Example: After touching a hot stove, you feel the
heat, and jerk your hand away.
Parts of the CNS
5. The spinal cord is the link between your
brain and other parts of your body.
Sometimes the spinal cord decides what
your body does. Reflexes are controlled
by the spinal cord.
6. The brain is made of billions of nerves
cells. It is protected by the skull.
Lesson 4
How does the body defend itself?
Lesson 4
1. Microorganisms can cause diseases in
your body if they don’t stay where they
belong. They are found on your skin, in
your mouth, and in your digestive
system. Most of the time, they are
harmless.
2. Your body uses special cells, tissues,
organs, and chemicals to keep the bad
microorganisms from causing harm.
Lesson 4--Fighters
3. Your skin is your first “fighter.” It provides
chemical protection.
4. Tears help protect diseases from
reaching your eyes. Saliva in your
mouth, mucus in your throat, and acid in
your stomach are other “fighters” found
in your body.
Lesson 4
5. Pathogens are organisms that cause
diseases. They do not belong in our
bodies and can cause infectious
diseases, which are contagious.
6. Bacteria and viruses are parts of
pathogens. Bacteria can cause strep
throat or food poisoning. Viruses invade
your nose, mouth, or throat and can give
you a cold.
Lesson 4--Fighting Back
7. Your immune system is made of
defensive cells and acts like your body’s
army. It protects you from many
pathogens.
8. A vaccine is a kind of medicine that
protects you from a disease. They are
not available for every disease.