2. systems
Several different systems make up the human
body
Every minute of everyday different systems work
together as a team to keep you alive and healthy
You probably know that you have a
heart, stomach, and two lungs. each of those parts
are called organs
Each organ in your body has it’s own job to do
Each of your body systems is made out of organs.
Your heart is an organ in the circulatory system.
Your stomach is an organ of the digestive system.
Your lungs are organs of your respiratory system.
3. Cells tissues and systems
• Other body systems are: skeletal
system, muscular, and nervous system. All organs
in your body work together and depend on each
other.
• Each organ in your body is made out of two
tissues or more kinds of tissues
• In fact, all living things are made out of cells
• You have hundred different kinds of cells. Muscle
cells, nerve cells, and bone cells.
• Muscle cells form muscle tissue. Muscles change
shape to help you move.
4. Tissues
Nerve cells form nerve tissues. Your brain
and nerve are both made out of nerve
tissues
Bones and muscles
The bones in your skeleton give you
shape. Your bones also support you
Bones also work with your muscles to help
you move the way you do
Parts of your skeleton also protect softer
organs
Your skull which protects your brain
5. Bones and muscles
The ribs form a cage which protects your heart
and lungs
Cartilage
When you were born, your body was mostly
made out of rubbery tissues called “cartilage”.
As we grow, some of the bones start to replace
most of the cartilage. However, some cartilage
remains. For example, your ear and the tip of
your nose are made of cartilage.
6. X-rays
pictures called “x-rays” help doctors
see broken bones
Because tissues are living, broken
bones can heal
A cast holds a broken bone in the
correct position while it mends
New bone cells begin to form
The place where two bones of the
skeleton meet is called the “joint”
7. X-rays
Joints allow movement. They give your skeleton
it’s ability to bend, twist and turn.
You have hinge joints in your elbows and knees.
Muscles
A muscle is a tissue that is made out of muscle
cells. Muscles have the job to make other body
parts move. Muscles also give your body it’s
shape and protect soft organs inside you.
Muscles can move bones because muscle cells
change their shape
This is why muscles work in pairs. One muscle
pulls a bone one way. Another muscle pulls the
bone the opposite way.
8. Muscles
• When biceps contract they pull the hand
towards the shoulder. The arm bends.
When the triceps contract, the muscles
pull the arm away from the shoulders. The
arm straitens out.
Kinds of muscles
• Arm muscles arm kinds of muscles
• Certain other muscles are : involuntary
muscles. They work even when you sleep.
For example, the muscles that move food
through your digestive system are
involuntary muscles.
9. Exercises
1- Say two jobs that body systems do.
2- Name one organ in each of these systems :
circulatory, digestive, and respiratory system.
3- What are organs made of ? What are tissues made up
of ?
4- How does the skeletal system help your body ?
5- How does a broken bone heal ?
6- What are the differences between two kinds of
muscles ?
7- Why is it important that your heartbeats and breathing
are controlled by involuntary muscles ?
8- How do joints help you move ?
9- What are two things muscles do ?
10- How do muscles help you move ?
10. Answers
1- Breathe in and out (respiratory) helps you read and think
(nervous).
2- Circulatory: heart
respiratory: lungs
digestive: stomach
3- Organs are made of different kinds of tissues. Tissues or made
of different cells.
4- The skeletal system give your body it’s shape and support your
body. (holds your body)
5- Because it’s a living tissue, it can heal.
6- Some muscles are involuntary and other are voluntary muscles
11. Answers (7—10)
7- It is important that our heart muscle is
involuntary so that it can still work in
activities such as sleeping.
8- Joints give the ability to bend, twist and turn.
9- Muscles help us move and protect our softer
organs.
10- Muscles work in pairs and in action
opposite too each other