The human skeleton: structure, function and its importance

El human skeleton The human body is one of the most complex structures in our body, providing mechanical support, protection to organs and facilitating movement. Over the years, it has been the subject of study due to the multiple functions it performs and the adaptive capacity it offers to humans to perform different physical activities. Here we will explore in detail how many bones are part of the human body, the different classifications of these and how they are organized to allow a wide variety of movements.

How many bones has the human body?

At birth, a human being has about 350 bonesHowever, as we grow, many of these bones fuse together, reducing the number to about 206 bones in adulthoodThis fusion process occurs mainly in the areas of the skull, spine, and pelvis.

Bone fusion: During childhood and adolescence, bone fusion is crucial to body development. Areas where bones fuse include the pelvis, where the three bones that make up the pelvis (ilium, ischium, and pubis) become the hip bone. The skull and spine also undergo bone fusion throughout the growth process.

The human skeleton: Main divisions

The human skeleton is divided into two large structures: the axial skeleton and the appendicular skeletonThis division simplifies the classification of bones according to their function.

axial skeleton

El axial skeleton forms the central axis of the body and includes:

• The skull, which protects the brain.
• The spinal column, composed of vertebrae that protect the spinal cord.
• The ribs and sternum, protecting the heart and lungs.

The axial skeleton is composed of 80 bones that allow it to protect the vital organs of the body.

appendicular skeleton

El appendicular skeleton It is made up of the bones of the upper and lower extremities, as well as the shoulder and pelvic girdles, which connect the limbs to the axial skeleton. This system includes:

• On arm bones: humerus, radius and ulna.
• On leg bones: femur, tibia and fibula.
• The shoulder girdles (clavicle and scapula) y pelvic, which provide stability and connect to the limbs.

Classification of bones according to their shape

The bones of the human body can be classified into five main categories according to their shape and function:

• long bones: Length predominates over width and thickness. Examples: femur, humerus.
• Short bones: They have more uniform dimensions. Examples: carpal bones (wrist).
• Flat bones: They are thin and provide protection. Examples: skull, sternum.
• irregular bones: They have complex shapes. Examples: vertebrae.
• Sesamoid bones: They develop within tendons. Example: patella.

Main functions of the skeleton

The human skeleton has multiple essential functions for the body:

• Mechanical support: Provides the framework that supports the body and allows for bipedal posture.
• Movement: Together with joints and muscles, it enables complex movements. Tendons connect muscles to bones to facilitate these movements.
• Protection: It protects vital organs such as the brain, heart and lungs.
• Production of blood cells: It takes place in the red bone marrow, located in certain long, flat bones.
• Mineral storage: Bones are the main storehouse of calcium and phosphorus.

How does movement occur in the body through the skeleton?

Movement is the result of the interaction of three main components:

• Muscles: Attached to bones via tendons, muscles exert force on the skeleton to generate movement.
• Joints: They are the connections between bones that allow both movement and stability. There are several types of joints: synovial, cartilaginous and fibrous.
• Nervous system: Nerves send signals to muscles, which contract to move bones across joints.

In addition, some joints, such as those in the skull, are designed to be immobile and protect the organs of the nervous system, while others, such as those in the shoulders and knees, retain great mobility.

Bones and bone marrow

Inside the bones is the bone marrow, which performs two essential functions:

• Red bone marrow: It produces red blood cells, white blood cells and platelets.
• Yellow bone marrow: It is found in many long bones and stores lipids.

These hematopoietic functions are crucial for maintaining a healthy blood system and for defending the body against diseases and necessary nutrients, such as oxygen.

Changes in the skeleton with aging

Over time, bones go through a process of remodeling, in which old bone cells are replaced by new ones. However, with age, bone density decreases, which can lead to problems such as osteoporosis, a disease that increases the risk of fractures.

In addition, some diseases that affect the skeleton can appear over time, such as rickets or bone cancer, conditions that require a specific diagnosis and treatment.

Bone fractures are also common in older ages due to the fragility of the skeletal system, and treatment for these injuries can range from casts to surgeries to fix the fractured bones.

In short, it is important to take care of your bones throughout your life with a diet rich in calcium, vitamin D and regular physical exercise.

The human skeleton is not just a support structure; it is a complex mechanism that plays a vital role in maintaining life, providing movement, protection, and blood cell production. The different classifications and divisions of the skeleton allow the human body to function optimally, and proper care of the skeletal system is essential for a long and healthy life.