Why do we have a skull

The skeleton

The skeleton is the framework of the body, it gives your body support, carries its weight and protects the sensitive organs. The skull protects the brain, the rib cage protects the heart, lungs and liver, and the pelvis protects the reproductive organs.

The bones also serve as mineral stores for calcium and phosphate and produce different types of blood cells.

The skeleton is made up of bones of all shapes and sizes. The largest bone is the thigh bone, the smallest the ossicle.
How we can move depends on the structure of the individual bones and joints.

The spine is at the center of our skeleton. It ensures that you can walk upright.

Before birth, the bone still consists of a soft filling tissue (mesenchyme), later cartilage forms from it and gradually the bones become hard.
In total, a person has 350 bones when he is born. Some later grow together so that the adult human has only about 206 bones.
The bones are moved by the muscles and joints that receive their orders from the nervous system.

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The skull
The skull forms the face and protects the brain. This is important because strong blows could injure the brain. That's why you also wear a helmet that cushions shocks for various sports.

The spine
The spine holds the head and trunk upright and allows the body to rotate and bend. It is the mainstay of the body. It also protects your spinal cord.

The joints
The bones are rigid, but the joints make them very flexible. Where two bones meet, they form joints.
There are very different joint systems for the different movements of the body:

Hinge: The hinge allows you to move your elbows and knees. It is the simplest form of joint.
Swivel Joint: It's located on the neck so you can turn your head. Some also say wheel joint.
Ball joint: The shoulder and hip are ball joints that can be moved from top to bottom and from front to back.
Saddle joint: This joint is only found at the bottom of the thumb. It can be moved in two directions, to the side and up and down.

So that the joints do not rub against each other, they are covered with articular cartilage and embedded in synovial fluid.
The intervertebral disc wiping the vertebrae also cushions the body.

Types of bones
Bones store various minerals such as calcium, phosphorus and magnesium. Living bones are not dry, they are moist. Various tasks for the body are performed in the bones. The shape indicates the task that the bone has to fulfill.
Long bones are long bones that act as levers, e.g. upper arm and thigh bones and the shin bone.
Plate bones are the top of the skull, shoulder blade and sternum. They have a protective function
Short bones, e.g. B. the talus and the root bones of the hands serve as bridges
Irregular bones are the vertebrae, some of the facial bones, and the iliac bone. For them, compressive strength and elasticity are particularly important.

The bone marrow
Some bones are hollow and contain the bone marrow that makes the red and white blood cells.
About half of the bone marrow is engaged in making red blood cells. It is therefore also called "red bone marrow". There is also another bone marrow with a lot of fat in the bone. It's called "yellow bone marrow". If necessary, it can be converted into red bone marrow and then also produce new blood cells.



Did you know, that....
....... the proportion of bones in the weight is only about 14%?

.... the proportion of body calcium in the bones is 99%?

..... that the smallest bone is the 'stirrup' in the ear and weighs only about 2-4 mg?

.. the tallest man who ever lived was 272 cm tall, the tallest woman 247 cm?

... the smallest man was 57 cm tall and the smallest woman 59 cm tall?

.... the heaviest man in the world weighed 635 kg?

... the lightest woman, aged 20, weighed 5.9 kg?

..... the first protective helmet was the soldier's and knight's helmet?

..... that a broken rib does not need a cast because it is held by the muscles?

.... the bones would be like rubber without calcium?




Some people are more flexible than others. In the circus or variety there are "contortionists" who are extremely agile. This requires constant and years of practice.


What else might interest you:

Why do bones break?

How does a broken bone heal?

Are there growing pains?





Why does man walk upright?

Why are we growing



Bone disease

Flat feet
disc prolapse
Broken bone
Bone cancer
Softening of the bones
Arthritis / osteoarthritis
Vitreous bone disease
Joint injuries


Body side
You can find more about the body at
My body and me