How Many Bones Are In The Human Body?

How many bones are in the human body? A human body is made up of 206 bones which forms a skeleton, skeleton provides structure, shape and support to a human body. Number of bones in human body is different in different age group. Infant skeleton contains 100 more bones then an adult skeleton. By the passage of time these bones then defuse to make single bones. There are five categories of bones: * Long bones * Short bones * Flat bones * Irregular bones * Sesamoid bones

Bones in human body:

Bones are the composition of calcium carbonate and calcium phosphate. It forms a skeleton of human body. It also serves as the protection of different organs. Most of the bones contain bone marrow which produce red and white cells, store minerals, enable movement and give shape and support of a human body.

How many bones are in human body?

Bones adult vs. infants:

An infant has more bones then an adult. Yes a baby’s skeleton contain 300 bones which is greater than an adult’s skeleton. The baby’s bone later grow together and defuse to form an adult skeleton having 207 bone.

Bones male vs. female:

Apparently male and female both have same number of bones i.e 207 bones. But bones of male skeleton is comparatively stronger, wider, thicker and high in density then a female bones.

Difference between male and female bones:
There are number of features which differentiate male skeleton from female. The differences are following:

  • Female frontal bone is rounded while male have less round frontal bone then a female skull.
  • Female has smooth brow bone while male have prominent ridge (brow).
  • Female has rounded eye orbit and male has square eye orbit.
  • Female skull has pointed chin and male skull has square chin as most of them contain square shape faces.
  • Female skull form obtuse angled jaw line while male skull has acute angled jaw line.
  • Female skeleton is smaller and lighter in weight while male has large and heavy skeleton.

Classification of bones:

According to the shape a human skeleton is classified into five categories of bones:

  1. Long bones
  2. Short bones
  3. Flat bones
  4. Irregular bones
  5. Sesamoid bones

Long bones:

Long bones are the bones which are longer than its width. They are cylinder in shape. Long bones are comparatively hard bones that gives our body strength, shape and helps in movement.

Example:

Long bones include the bones of:

  • Arms (humerous, ulna, radius)
  • Legs (femur, tibia, fibula)
  • Finger (metacarpals, phalanges)
  • Toes (metatarsals, phalanges)

Short bones:

Short bones are equal by mean of length, width and thickness. They are cubic in shape. These bones also help in some amount of mobility, provide support and strength of a human body.

Example:

Short bones of a human body include the bones of:

  • Wrists (carpals)
  • Ankle (tarsals)

Flat bones:

Flat bones are usually thin and curved, it works as an adhesive for muscles and also protects internal organs.

Example:

Example of flat bone are:

  • Skull bones (cranial)
  • Shoulder blades (scapulae)
  • Breast bone (sternum)
  • Ribs

Irregular bones:

Irregular bones as its name define that it is irregular in shape that’s why it does not lie in any of the above mentioned category. It is complex and does not have any define shape. It also protects internal organs.

Example:

Example of this most complex bones include:

Sesamoid:

Sesamoid bones are small round shape bones which looks like sesame seed. These bones are found in tissues which connect bones with muscles (tendons) which protect tendons from heavy pressure and stress. The number of sesamoid bones can vary from person to person.

Example:

The patellae is the only example of sesamoid bones.

Bones in human body:

There are approx. 300 bones in human body by birth which is reduce and become 206 bones in adulthood. Bones are the fundamental part of the human skeletal system. Following is the list of bones which is found in human skeleton:

  • skull (forehead, brow bone and jaw bones)
  • spine (lumbar vertebrae, tail bone)
  • chest (ribs, chest bone)
  • arms (shoulder blade, collar bone, humerus)
  • hand (carpals, meta carpals, phalanges)
  • pelvis (hip bone)
  • legs (thigh bone, knee cap, fibula)
  • feet (tarsals, metatarsals, phalanges)

The skeleton:

The human skeleton is a framework of body which provide support, movement, protection of internal organs, production of red blood cell and storage of minerals. The number of bones in male and female skeletal system is almost same but female contain penile bone which helps in childbirth.
A human skeleton can be divided into two parts:

  • Axial skeleton
  • Appendicular skeleton

Axial skeleton:

Axial is derived from the word Axis which means central point. Axial means the bones of axial skeleton located along with the center of body. Axial skeleton is the part of skeleton which contains the bones of major part of a human body, i.e. bones of head and vertebrate. Axial skeleton consists of 80 bones which includes:

  • Skull
  • Rib cage
  • Vertebrate column

Skull:

A human skull contain 22 bones including cranium and facial bones. Cranium has the important function to protect human brain while there are 14 facial bones in human skull which gives the shape to human face. A human infant has 8 separate plate in their head which later fuse together and form a skull.

Rib cage:

A rib cage contain 12 pair of ribs and a sternum of 25 separate small bones. It protects the vital organs of human body such as: heart and lungs. It looks like crescent with one flattened and other is rounded. The rounded end joint with vertebrae at the back and flattened end come together at front.
The rib cage is further divided into three types:

  • True ribs (upper seven pair of ribs attach with cartilage)
  • False ribs (8th to 10th pair of ribs which does not attach with cartilage)
  • Floating ribs (the last two ribs do not attached and simply float or hanging)

Did you know?
The first rib of the cage is comparatively short, flat and more curved then other rib.

Vertebral column:

Vertebral column is the longest series of bones which join skull with pelvic bones and also gives support to the rib cage. At the time of birth a human have 33 vertebrae which then later fuse together and becomes 24 in normal development. The vertebral column consists of 5 parts:

Summary:

There are 80 bones in Axial Skeleton:

  • Skull, which contain 22 bones.
  • Middle ear ossicles which contain 6 bones (3 bones in each ear)
  • 1 bone in neck which named hyoid
  • 26 bones of vertebral column
  • Chest bone
  • 12 pair of ribs i.e. 24 bones

Appendicular skeleton:

Appendicular skeleton is another set of bones which includes bones of upper and lower limbs, shoulder and pelvic. It involves in mobility more than axial skeleton. It contains 126 bones which includes:

  • 4 bones of shoulder girdles
  • 6 bones of arms and forearms
  • 54 bones in hands including fingers and wrist
  • 2 bones of pelvic
  • 8 bones of thigh and legs
  • 52 bones of foot including fingers and ankles.
    Appendicular bones further divided into two types:
  • The bones that are located within the limbs.
  • The bones which attach limbs with axial skeleton.

Did you know?
There is one bone in human body which is not connected with any other bone and that bone is hyoid bone (bone in tongue)

Function of skeleton:

Skeletal system:

Skeletal system is the framework of human body which consists of bones (the essential component), tissues (connective tissues), cartilage, tendons and ligaments.

Function:

Except providing support, shape and movement of human body the skeletal system of a human body serves in the following ways:

  • Produce blood cells: bones contain bone marrow which is responsible to produce red and white blood cells.
  • Protects vital organs: it support and protect the vital organ of human body, bones in human skeletal system include skull (which protects brain), rib cage (protects heart and lungs) and vertebral column (protects spinal cord).
  • Store and supply minerals: bones of human body store and supply minerals of human body such as calcium and vitamin D.

Bones layers:

Each bone of human skeleton (any type of bones) contains these layers:

  • Periosteum
  • Compact bones
  • Spongy bones
  • Cartilage
  • Joints
  • Ligaments
  • Tendons

Periosteum:

Periosteum is the outer surface of the bone in human body. It contains connective tissues wrap around all over the bone except joints spaces. Periosteum layer help in defining shape of bones in growing period and it also help in recovery of bones.

Compact bones:

It is the heaviest and strongest layer of the bone which is also known as cortical bone. It has to be very hard because it gives support to the muscles during mobility also it is responsible for store and release minerals.

Spongy bones:

Spongy bones are comparatively soft then cortical bone or compact bone. It is the inner layer of bone which is also known as cancellous bone. It is usually found near joints and inside the vertebrae. It contains small holes which is the house of bone marrow, these holes are involve in production of red blood cells.

Cartilage:

Cartilage is the smooth substance present on the tip of every joint of bone which helps in reduction of friction in bone and provide then mobility without rubbing with each other.

Joints:

Joints are the area where bones meet together and allow body to move. There are three types of joints:

  • Immoveable joints: these joint can join bones together but never allow them to move. The joints of skull bones are the example of immoveable joints.
  • Partially moveable joints: these joints of bone can move but have very limited mobility or very less movements. Joints of rib cage is the example of partially moveable joints.
  • Moveable joints: these joints can move in wide range. Example of moveable joints are: shoulder, elbow, knees.

Ligaments:

Package of connective tissues which hold bones with each other. It limits the joints to move abnormally to protect bones from injuries due to stretching. There are 900 ligaments in human body.

Tendons:

Package of connective tissues which connect muscles with bones.

Synopsis:

A bone of human body is the composition of Periosteum, Compact bones, Spongy bones, Cartilage, Joints, Ligaments and Tendons. The outer surface of a bone enveloping with connective tissues are known as PERIOSTEUM which helps in modeling or giving shape of bone and recover from injury. COMPACT BONES are the hardest layer of bone which protects internal layers of bones. The bone marrow holes are present in SPONGY BONES are soft inner layer of bone then comes CARTILAGE which works as the greasing substance for bones which provide rub free movement. The point where bones meet together is JOINT. LIGAMENTS and TENDONS are almost similar but ligaments holds bones with each other while other one connects muscles with bones.

Bone cell:

There are three types of bone cell:

  • Osteoblasts: involve in formation of bone cells.
  • Osteoclasts: manage break down and absorption of bone tissues.
  • Osteocytes: these are complete and mature blood cells.

Bone disease:

Some of the common bone diseases include:

  • Bone infection
  • Bone cancer
  • Rickets

Summary:

A human body consists of 206 bones which develop skeletal system of human body. Skeleton provide shape, structure and protection of human body. There are two parts of skeletal system i.e. axial skeleton and appendicular skeleton. Axial skeleton holds major parts of human body while on other hand appendicular skeleton decorates the axial skeleton. Bone of human body further divided into five types, long bones, short bones, flat bones, irregular bone and sesamoid. A complex human bone is layered with periosteum, compact bones, spongy bones, cartilage, joints, ligaments and tendons.

FAQs:

1. Does male skeleton is different from female skeleton?

Not exactly! The number of bone either in male or female are same but the only difference between both skeleton is the skeleton of male is heavy, strong and high density then a female.

2. Why a child have different number of bones then an adult?

All 300 bones of infant body are not actually bones some of them are cartilage which become strong when they grow up and some of them fuse and grow together.

3. What is the shortest bone of human body?

“STAPES” are the shortest bone of human body which is present in the middle ear.

4. What is the longest bone of human body?

“FEMUR” is the longest bone of human body of 19.9 inches in length. It is commonly known as thigh bone.

5. Why we called a bone irregular?

An irregular bone can vary from person to person by mean of its shape and size. The shape of irregular bone is not fixed that’s why it does not lie in any category of bone and known as irregular bone.

6. What is the reason which increased risk of fracture in bone?

The chances of fracture increase due to a bone diseases called osteoporosis. It cause decrease in bone mass and minerals.

7. What are the floating ribs?

Floating ribs are top most rib of cage which is hang freely and does not connected like others. It is more curved and deep then other rib.

8. What is the key difference between axial skeleton and appendicular skeleton?

Axial skeleton is the part of skeleton which holds the bone of main parts of human body like skull, rib cage and vertebrae which protects the vital organs of human body while appendicular skeleton is the accessory of axial skeleton and contains the bone of upper and lower limbs and shoulder.

9. What connects bones with each other?

“LIGAMENTS” are the package of connective tissues which holds or connects bones with each other.

10. Which bone contains bone marrow?

SPONGY BONES are the inner layer of bone which contain holes for bone marrow.

11. Is tongue part of skeletal system?

No! The tongue is itself not the part of skeletal system but it contains a horse shoe shaped bone in neck which somehow connect with vertebrae column.

12. Which area of bones does not contain periosteum layer?

A bone is covered with periosteum layer which is envelop with connective tissues. It heels bone injury faster. The joint surface is the only area which does not connected with periosteum layer.

13. Which bone is weak in human body?

The collar bone is consider as the weakest bone of human skeletal system.

14. What are bone tissues?

There are two types of bone tissues: cortical and cancellous, cortical or compact bones are the hardest tissue which is the outer surface of bone and covers and protects all inner layer while cancellous bone or spongy bones are soft inner layer of bone which contain bone marrow.

15. Is number of ligaments different in infants from adults?

The number of ligaments is equal in both infants and adults i.e. 900 but the infant bones’ ligaments are softer than an adult and can be slip easily with minor stress.

16. A body without bone is possible?

No way! A body can never survive without bones. With the absence of bone a body will look like a sac of skin having different organs and fats. As only the bone is responsible for maintain the shape of body.

17. What is the rare bone diseases?

The rare bone diseases is scientifically termed as Gorham-Stout diseases in which bone loss occurred. Infected bones start vanishing or start abnormal growth.

18. Tooth is bone?

Teeth also have minerals, blood vessels and cells but it cannot consider as bone because it doesn’t grow together if broken or they cannot regenerate themselves.

Related Articles:

  • Bones are made up of connective tissue reinforced with calcium and specialised bone cells.
  • The body is constantly re modelling the skeleton by building up new bone tissue and breaking down old bone tissue as required.
  • Healthy bone needs a balanced diet, regular weight-bearing exercise and the right levels of various hormones.
    Bones provide the structure for our bodies. The adult human skeleton is made up of 206 bones. These include the bones of the skull, spine (vertebrae), ribs, arms and legs. Bones are made of connective tissue reinforced with calcium and specialized bone cells. Most bones also contain bone marrow, where blood cells are made. Bones work with muscles and joints to hold our body together and support freedom of movement. This is called the musculoskeletal system. The skeleton supports and shapes the body and protects delicate internal organs such as the brain, heart and lungs. Bones contain most of our body’s calcium supply. The body is constantly building up and breaking down bone tissue as required. Healthy bone needs a balanced diet, regular weight-bearing exercise and the right levels of various hormones.
    Bone types:
    There are four different types of bone in the human body:
  • Long bone – has a long, thin shape. Examples include the bones of the arms and legs (excluding the wrists, ankles and kneecaps). With the help of muscles, long bones work as levers to permit movement.
  • Short bone – has a squat, cubed shape. Examples include the bones that make up the wrists and the ankles.
  • Flat bone – has a flattened, broad surface. Examples include ribs, shoulder blades, breast bone and skull bones.
  • Irregular bone – has a shape that does not conform to the above three types. Examples include the bones of the spine (vertebrae).
    Bone tissue:
    The different layers of bone tissue include:
  • Periosteum – the dense, tough outer shell that contains blood vessels and nerves
  • Compact or dense tissue – the hard, smooth layer that protects the tissue within
  • Spongy or cancellous tissue – the porous, honeycombed material found inside most bones, which allows the bone to be strong yet lightweight
  • Bone marrow – the jelly-like substance found inside the cavities of some bones (including the pelvis) that produces blood cells.
    Bone marrow:
    Bone marrow is where blood cells are made. The three different types of blood cell made by bone marrow include:
  • Red blood cells – carry oxygen around the body.
  • White blood cells – make up the body’s immune system.
  • Platelets – are used for clotting.
    Bone cells:
    Our body is constantly re modelling its skeleton by building up and breaking down bone tissue as required. As a result, each bone is rebuilt from scratch about every decade. The bone cells involved in this process include:
  • Osteoblasts – the cells that build bone tissue
  • Osteocytes – the cells that maintain bone tissue by controlling the mineral and calcium content
  • Osteoclasts – the cells that break down old bone tissue.
    Bone density:
    Many factors work together to ensure the strength and health of bones. Bone density relies on:
  • A steady supply of dietary calcium
  • Adequate vitamin D from sunshine and food
  • A healthy diet with plenty of vitamins and minerals
  • Various hormones including parathyroid hormone, growth hormone, calcitonin, oestrogen and testosterone
  • Regular weight-bearing exercise.
    Bone conditions:
    Some conditions of bone include:
  • Fractures – broken bones of various types
  • Osteoporosis – loss of bone density and strength
  • Osteomyelitis –­ infection of the bone
  • Osteitis –­ bone inflammation, for example, Paget’s disease of the bone
  • Acromegaly – overgrowth of bones in the face, hands and feet
  • Fibrous dysplasia – abnormal growth or swelling of bone
  • Rickets – a child’s growing bones fail to develop due to a lack of vitamin D
  • Multiple myeloma – cancer of the plasma cells in bone marrow
  • Bone cancer – primary bone cancers include osteosarcomas and chondrosarcomas. However, most cancers found in bone have spread from other organs such as the breast, prostate, lung or kidney.
    The skeleton:
    The human skeleton is made up of 206 bones, including bones of the:
  • Skull – including the jaw bone
  • Spine – cervical, thoracic and lumbar vertebrae, sacrum and tailbone (coccyx)
  • Chest – ribs and breastbone (sternum)
  • Arms – shoulder blade (scapula), collar bone (clavicle), humerus, radius and ulna
  • Hands – wrist bones (carpals), metacarpals and phalanges
  • Pelvis – hip bones
  • Legs – thigh bone (femur), kneecap (patella), shin bone (tibia) and fibula
  • Feet – tarsals, metatarsals and phalanges.