We can move. unit 3

CBM Los Pinos

Our body is made up of our head, torso and limbs.

HEAD

LIMBSTORSO

The locomotor system is what lets us move the different parts of our bodyand allows us to move around.We can move our body in many ways:

We can runWe can jumpWe can walk

The locomotor system includes bones, joints and muscles.

All the bones in our body make up the skeleton

We have muscles around many of these bones.

Most bones are connectedat joints.

The skeleton is made up of all the bones in our body.

An adult has 206 bones. But a baby has more!A baby has about 300 bones! This is because some of our bones join together as we grow.

Bones are hard and rigid. They are very strong and they don’tbend.

The skeleton has three parts:

Skull

Torso

Limbs

The skeleton has two functions:

It supports our body It protects the delicate organs inside our body

The skull protectsour brain.

The ribs protect our heart and lungs.

The bones in our body are all different shapes.

There are three types of bones:

Some are short.

Vertebrae are short bones.

Some are long.

The tibia is a long bone.

Others are flat.

Our skull is made up of flat bones.

There are long bones in our arms and legs.

Long bones

Long bones

There are short bones in our spine, hands and feet.

Spine Hand Foot

There are flat bones in our skull,ribs, pelvis and scapula.

Skull

Scapula

Ribs

Pelvis

Can you remember the name of some joints in our body?

JointsWrist

Knee

Shoulder

Hip Elbow

Ankle

Our bones are connected at joints.

Shoulder

ElbowWrist

Hip

Knee

Ankle

Some joints allow our bones to move a lot. We call these flexible joints.

The joints in our knees

Our elbow

and shoulders are all flexible joints.

Some joints only let our bones move a little.We call these semi-flexible joints.

Our spine has semi-flexible joints.

The vertebrae in our spine are semi-flexible joints.

Some bones are connected at joints that can’t move.

We call these fixed joints.

The joints in our skull are fixed joints.

Muscles

Muscles are soft when relaxed.

Most muscles are connected to bones.

Muscles move our bones by contracting and relaxing.

When muscles contract, they get shorter. When muscles relax, they get longer.

The Biceps and the Triceps work together.

When the biceps relax, the triceps contract.

When the biceps contract, the triceps relax.

We have two types of muscles

Voluntary Involuntary

We can move voluntary muscles when we want.

We can’t control involuntary muscles.They move automatically.

When we dance, run, jump,… Our heart is an involuntary muscle.It moves all the time without us thinking about it. Even when we are asleep!

There are over 600 hundred muscles in our body, and every muscle has a special function.

In our arms there are biceps and triceps.

Biceps

Triceps

We use these musclesto write, play tennis or pick things up.

In our legs there are biceps, quadriceps and calf muscles.

Biceps

Calfmuscles

Quadriceps

These muscles help us walk, run and jump.

In our shoulders there are deltoids.

Deltoids

The trapezius muscle is in our back.It helps us move our arms.

Trapezius

In our chest there are pectorals.

Our abdominals are near our stomach.

These muscles help us bend down.

Abdominals

We also have many muscles in our face. The masseter help us chew our food.

Masseter