23 Aug

Skeletal System 206 Bones In The Body And Their Functions – AC

The 206 bones in the body and Their Functions

As might already be known to you, the human being skeleton is made up of 206 bones bones in human body that may vary in number from individual to individual depending on various factors. A lot of other factors affect these factors in unpredictable manner, such that it cannot be accurately determined that a certain individual has a certain number of bones in the body. It is also worth noting that some of these bones are fused with each other such that some scientist have reached a point where they think the bones are actually less than 206.

Point noted that these bones vary from individual to individual, but their functions do not really vary. In this article, we are going to discuss the functions of the 206 bones in human body. Their functions are definite in all individuals, which is where all the variations cease to exist. Therefore, without wasting much time, here we go. The bones in the body, broken down by parts and their functions:

Human body bones Skeletal system

Skeletal system 206 bones in the body and Their Functions

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Vertebral column bones in human body

Vertebral column bones

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The vertebral column, also known as the backbone, is unsurprisingly made of several bones for the sake of flexibility.  Here they are:

The spinal vertebrae of the vertebral column (33 bones)

The spinal vertebrae make up the larger part of the whole vertebral column. They make up the longer chain of the most flexible bones in the body.

The cervical vertebrae (7) : These are the smallest in the uppermost positional location in the spinal column. These support the skull, move the spine and protect the spinal cord which is a bundle of nerves that run throughout the vertebral column to the brain.

The thoracic vertebrae (12) : These have a rather too important function.  Together, these bones function to hold the rib cage and protect the heart and the lungs. They form the anterior articulatory surface for the ribs.

The lumbar vertebrae (5) : The lumbar bears the weight of the body. Sounds a little excessive, but the five are very efficient in their task.

The sacral vertebrae (5 at birth, later fused into one) : Also known as the sacrum, the main function of these bones is to connect the spine to the hip bones (iliac). They are separate at birth, but later in life, they are fused together to form one structure, the sacrum.

The coccygeal vertebrae (4 at birth, later fused into one) : Commonly called the coccyx, the four, later fused, bones provide attachment surface for muscles and ligaments of the pelvic floor. However, studies show that the functions of these bones are no longer required and therefore, are vestigial organs.

Chest bones in the body

Chest bones in the body

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The chest is a body structure and many people do not realize this straight away. In fact, out of all bones in the body, the chest bones are the most packed together, showing the level of criticality of the functions they perform.

The sternum (1):  the sternum is a long flat bony plate connected to the rib bones. Its functions are to form an articulatory surface for ribs as well as protection of the delicate organs that lie below it.

The ribs (24, in 12 pairs), made up of:

  • 3 pairs (the 8th, the 9th and the 10th pairs), usually referred to as false ribs are attached at the front to each other and to the 7th rib via cartilages and other joints
  • 2 pairs of floating ribs (11th and 12th pairs), have no anterior attachment.
  • Cervical ribs

The ribs generally form a protective armour as well as form a cavity within which lungs, the heart and other vital organs.

Skull bones

Skull bones external-anatomy-of-the-lateral-skull-right-side

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The skull is made up of several different bones, though fused together to seem like one, are still different bones. More than any where else where bones in the body pack together, bones in the skull form an almost air-gapped enclosing in which the brain is jealously protected.

The cranial bones (8)

Commonly called the cranium, these bones are fused and work to perform the same functions:

The occipital bone: found at the base of the skull, it provides an excellent articulatory surface between the skull and the first cervical bones.

The parietal bones (2): the two large parietal bones make up part of the roof and sides of the human skull, which act as protective cover on the brain and nerve networks in the human head

The frontal bone: this bone forms the front of the skull and has interestingly simple function, which is protecting the brain from mechanical damage. This explains why it is so hard to crack.

The temporal bones (2):  The temporal bones have several borders that make them suitable as joining borders between bones. They also have processes that provide a much broader articulatory surface.

The sphenoid bone: this bone has a butterfly-like shape that makes up its complexity and increases its interactivity with various bones.

The ethmoid bone:  this is a small bone in the skull that separates the nasal cavity from the brain and has the function of making sure activities in the two cavities remain separated.

The facial bones (15)

facial bones

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These, obviously, are the bones that make up the face and give it its shape. Whereas some versions of human anatomy count out some of the bones listed below in the facial bones, this article cannot omit them as they are still part of the whole unit of bones in the body.

The nasal bones (2): these are paired bones that form the anterosuperior bony roof of the nasal cavity. As might be guessed already, they prevent the nasal cavity from collapsing, thus making sure it remains open.

The maxillae (upper jaw) (2): It houses the teeth and forms the roof of the oral cavity. It also forms the floor of the lateral wall, and sometimes considered as part of it.

The lacrimal bone (2): form the medial wall of the orbit, thus easily articulating with the frontal bones.

The zygomatic bone (2): the zygoma forms the lateral portion of the inferior orbital rim. It also forms the anterior zygomatic arch, which essentially form the eye socket.

The palatine bone (2): form the roof of the mouth and floor of the orbit.

The inferior nasal concha (2): spongy in nature so that they effectively increases the surface are of the nasal cavity.

– The vomer: this bone lies at the base of the nasal cavity and forms the nasal septum.

– The mandible (lower jaw): is a U-shaped bone, and because it houses the teeth, its motion is essential for mastication of food.

The hyoid bone: it is even sometimes ignored as a facial bone, thus the ambiguity of its functions.

In the middle ears (6)

middle ears

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Who would ever know that bones actually aid in hearing? It gets to a point where the bones in the body actually begin to behave funny. Here are the 3 (very funny) bones that enable sound waves to be converted into the right format before being traversed through various media.

Malleus (2): initially vibrates as a result of perception of sound. Its vibrations are quick and accurate in relation to the sound waves.

Incus (2): receives vibrations from the malleus and also vibrates accordingly so that sound waves are properly converted to vibrations which travels though liquids.

Stapes (2): receives the vibrations from incus and finally submits the vibrations to the oval window into the liquid medium in which sound itself does not travel, but vibrations do.

Arm bones


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The human arm, as expected, is made up of several bones, though not as hard or as overly protective as some of the bones in the body already discussed. These bones include:

The bones of the upper arm (6 bones, 3 on each side)

The clavicle (collar bone): this is a slightly S-curve shaped bone that forms the attachment point between the arm and the chest.

The scapula: it provides a flat triangular surface for attachment of many muscles required to move the shoulders and the arms.

The humerus: being the only bone in the upper arm, it forms the attachment surface for muscles, as well as performing other functions of long bones generally, such as having a bone marrow that is used in a lot of areas in the body.

The bones of the lower arm (4 bones, 2 on each side)

The ulna: being the longer and larger of the two bones, forms joints with the humerus and the hand.

The radius: together with the ulna, they support the lower arm, form attachment surface for muscles and well as articulate with neighbouring bones.

The hand (54 bones, 27 in each hand)

The hand

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The carpals, include:

Scaphoid bone (2)

Lunate bone (2)

Triquetrum bone (2)

Pisiform bone (2)

Trapezium (2)

Trapezoid bone (2)

Capitate bone (2)

Hamate bone (2)

They form the wrist joint with the ulna and radius of the forearm and also form joints with the metacarpals. They form many gliding joints with each other to increase the flexibility of the wrist.

-The metacarpals (10, 5 on each hand): long and cylindrical, they form the supporting framework of the hand.

-The phalanges of the hand: they support and move the digits of the hand. They include:

Proximal phalanges (5 × 2=10)

Intermediate phalanges (4 × 2=8)

Distal phalanges (5 × 2=10)

Leg bones

Leg bones

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The leg bears most of the weight of the person. Of all bones in the body, the leg bones are the ones on which the highest expectations are placed. Essentially, in order for the leg bones to support the weight of the person, the bones must be strong enough and must have some way of creating a large surface area in order to spread the pressure and easily achieve balance.

-The coxal bone (hip bones, has 3 regions: ilium, ischium, and pubis (2)): together, they form the pelvic bone, which protect the delicate organs found in the pelvis. They also push aside to allow for childbirth in females.

-The sacrum and the coccyx: nearly useless in the modern human being, these two bones form a part which is used in attachment of muscles.

-The femur: this is the heaviest, largest and the strongest bone in the human body. It provides a surface for attachment of muscles in the thigh area.

-The patella (knee cap): this is a meniscus-like layer of tough fibrocartilage that acts as a shock absorber.

-The tibia: supports most of the body weight in the lower body.

-The fibula: supports muscles of balance in the lower leg and ankle.

The foot (52 bones in total, 26 per foot)

foot bones

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The foot itself, though used in soccer and rugby, is supposed to be the part that keeps the human being balanced and on support.

-The tarsals

Calcaneus or heel bone (2)

Talus (2)

Navicular bone (2)

Medial cuneiform bone (2)

Intermediate cuneiform bone (2)

Lateral cuneiform bone (2)

Cuboid bone (2)

Working together with the metatarsals, they work to support the body weight when one is standing upright.

-The metatarsals (10): Working together with the tarsals, they work to support the body weight when one is standing upright.

-The phalanges of the foot

Proximal phalanges (10, 5 on each side)

Intermediate phalanges (8, 4 on each side)

Distal phalanges (10, 5 on each side)

They connect to several muscles in the leg via long tendons and can flex or extend to change shape of the foot.

Sesamoid bones


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While a lot of these bones have had their functions discussed already, it is worth the time to redo their discussion. The name “sesamoid” comes from the fact that these bones look like sesame seeds in appearance and shape.

Together, these bones allow for flexibility and because they have already been discussed, they will only be listed without any kind of lengthy or even short discussion. They include:


-Pisiform bone


-Cyamella (bone)

Sesamoids in first and second metacarpal bones

Sesamoids in first metatarsal bone

Inconsistent sesamoids on other fingers and toes

-Lenticular process of the Incus bone

-Rider's bone

Inconsistent sesamoids in legs, arms, andbuttocks

Thus, that makes up the summary of all the 206 bones in the body, making an easy way into the study of bones in the body.

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