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Biology 2nd Baccalaureate

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Skip navigation Bones of the human body

Axial skeleton

It forms the axis of the body and has the function of protecting its soft parts. It is formed by:

Skull bones

Its function is to protect the brain. The skull is made up of:

  • Parietals: supports the meninges.
  • Temporary: they contain the ear.
  • Frontal: it is the base of the forehead.
  • Occipital: it has a hole that allows the passage of the spinal cord.
  • Sphenoid: at the base of the skull.
  • Ethmoid: between the sphenoid and the frontal bone.

Bones of the face

They are responsible for protecting the sense organs. Are composed of:

  • Upper jaws: occupy the center of the face.
  • Unguis or lacrimal: in the internal part of the orbit.
  • Zygomatic or malarial: they form the cheekbones of the cheeks.
  • Nasal: make up the upper part of the nose.
  • Lower turbinates: they are located inside the nostrils.
  • Palatine: they are located behind the maxilla, and contribute to the formation of the nostrils.
  • Vomer: it is part of the nasal septum.
  • Lower jaw or mandible: located in the lower part of the face.

Huesos de la cabeza

By Original by LadyofHats. Translated by Ascánder. [Public domain], via Wikimedia Commons


The spinal column protects the spinal cord. It is made up of vertebrae, separated by the intervertebral discs. It is divided into several regions:

  • Cervical. Composed of seven vertebrae that make up the neck , designed to allow head movements.
  • Dorsal. Twelve vertebrae that join the ribs.
  • Lumbar. Formed by five vertebrae.
  • Sacra. The sacrum is made up of five welded vertebrae.
  • Coccyx. The coccyx or coccyx is made up of four or five joined vertebrae.

Huesos de la columna vertebral: vértebras

By Nenamoralessalazar (Own work) [CC BY-SA 4.0], via Wikimedia Commons

Rib cage

The rib cage is made up of:

  • The sternum. Located vertically in the middle of the rib cage. It is attached to the clavicles and the first ribs.
  • The ribs:
    • Real ribs. Seven ribs attached behind to the dorsal vertebrae and in front to the sternum by means of cartilage.
    • False ribs. There are three ribs on each side, which are joined, behind, with the vertebral column and, in front, between them and the last true ribs by means of cartilage.
    • Floating ribsThe last two ribs on each side, joined behind with the vertebral column, and free in front, without joining the sternum.

Tipos de costillas: verdaderas, falsas y flotantes

Basado en By Cristobal carrasco (Own work) [Public domain], via Wikimedia Commons

Interactive activity: The bones of the trunk.

Appendicular skeleton

It is made up of the 126 bones that are part of the upper and lower extremities and the shoulder and pelvic girdle.

Shoulder girdle

  • Clavicle: it is a thin, flat bone shaped like an italic "s". It is articulated with the shoulder blade and sternum.
  • Shoulder blade or scapula: large, flat, triangular bone that articulates with the clavicle and humerus.

Upper limbs

  • Humerus: it is the longest bone in the arm, articulated in its upper part with the shoulder blade, and in its lower part with the ulna and radius, through the elbow joint.
  • Ulna: it is a long bone, parallel to the radius, articulated superiorly with the humerus, and inferiorly with the radius and the carpal bones. It is located on the inside of the forearm.
  • Radius: long bone on the outside of the forearm, located outside the ulna.
  • Hand: the bones of the human hand are:
    • Carpus: the wrist is made up of 8 carpal bones arranged in two groups of 4.
    • Metacarpus or palm: 5 bones, one metacarpal for each finger.
    • Phalanges: 14 bones that make up the fingers. All fingers have three phalanges, except the thumb, which has only two.

Huesos de las extremidades superioresBy Torax (Own work) [GFDL or CC BY-SA 4.0-3.0-2.5-2.0-1.0], via Wikimedia Commons

Pelvic girdle

The pelvic girdle is made up of a pair of hip bones, joined in front and behind, fused with the sacrum. This structure is known as the pelvis.

Each hip bone is formed by the union of three bones:

  • Ilium: it is the largest bone in the pelvis. It is attached to the sacrum. Shape the hips.
  • Pubis: it is located in the front part of the pelvis.
  • Ischium: lower and posterior part of the pelvisIt is the bone that we lean on when we are sitting.


By derivative work: LP (talk)Pelvis_diagram.png:Je at uwo at en.wikipedia (Pelvis_diagram.png) [Public domain], from Wikimedia Commons

Lower limbs

  • Femur: it is the thigh bone, the longest and strongest in the human body. It is articulated with the pelvis and knee.
  • Patella: small triangular bone located on the anterior aspect of the knee.
  • Tibia: long bone shaped like a triangular prism located on the inside of the leg. It articulates with the femur and with the ankle.
  • Fibula: long, thin bone, parallel to the tibia.
  • Foot: the bones of the human foot are:
    • Tarsus: seven bones, arranged in two rows, that constitute the back of the foot, between the bones of the leg and the metatarsals.
    • Metatarsal: five bones, one for each toe, that make up the midfoot.
    • Phalanges: they are the long bones that make up the fingers, three for each finger, except the big toe, which only has two.

Huesos de las extremidades inferiores: cadera y pierna

Domino público

Game: Bones of the human body.

Activity: The bones of the human body.

Game: Parts of the skeleton.

Activity: The names of the bones of our skeleton. (No registration required)

Game: Human Bones.


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