How many bones are in the body

Bones provide structure for our body. The skeleton of an adult is made up of 206 bones. These include the bones of the skull, spine (vertebrae), ribs, arms and legs. Bone is made up of connective tissue reinforced by calcium and specialized bone cells. Most bones also contain bone marrow, which makes blood cells.

Bones work with muscles and joints to hold our bodies together and support freedom of movement. This is called the musculoskeletal system. Bone supports and shapes the body, and protects fragile internal organs such as the brain, heart, and lungs.

Bones contain most of our body's calcium supply. The body continuously builds and breaks down bone tissue as needed. Healthy bones require a balanced diet, regular weight-bearing exercise, and appropriate levels of various hormones.

The Skeleton

The human skeleton consists of 206 bones, including:

  • Skull-including jaw
  • Spine-cervical spine, thoracic and lumbar spine, sacrum and coccyx (coccyx) 
  • Chest-ribs and sternum (sternum)
  • Arm-scapula (scapula), clavicle (clavicle), humerus, radius and ulna
  • Hand- -Carpals (carpals), metacarpals and phalanges, 
  • Pelvis-hips
  • Legs-thighs (femurs), kneecaps (patellas), tibias (tibias) and fibula
  • Feet-tarsals, metatarsals and phalanges

Bone types


There are four different types of bones in the human body:

  • Long bones have an elongated shape. Examples include the bones of arms and legs (excluding wrists, ankles, and kneecaps). With the help of muscles, the long bones act as leverage and allow movement.
  • The short bones are squat, cube-shaped. Examples include the bones that make up the wrists and ankles.
  • Flat bones have a flat, broad surface. Examples include ribs, shoulder blades, sternum and skull.
  • The shape of irregular bones does not meet the above three types. Examples include the spine (vertebrae).

Bone tissues


The different layers of bone tissue include:

  • Periosteum-a dense, tough shell containing blood vessels and nerves
  • Dense or dense tissue the hard, smooth layer that protects the internal tissue
  • Sponge or cancellous tissue-a porous honeycomb material found in most bones, which makes the bone both strong and light
  • Bone marrow-a jelly-like substance found in the cavity of certain bones (including the pelvis) that produces blood cells.

Bone marrow


Bone marrow is where blood cells are made. The three different types of blood cells made by bone marrow include:

  • Red blood cells carry oxygen around the body. 
  • White blood cells constitute the body's immune system.
  • Platelets are used for blood clotting.

Bone cells


Our body continuously reshapes its bones by building and breaking down bone tissue as needed. Therefore, every ten years or so, every bone will be rebuilt from scratch. The bone cells involved in this process include:

  • Osteoblasts are cells that build bone tissue. 
  • Osteoblasts are cells that maintain bone tissue by controlling mineral and calcium content. 
  • Osteoclasts are cells that break down old bone tissue.

Bone density


Many factors work together to ensure the strength and health of the bones. Bone density depends on:

  • A stable supply of dietary calcium. 
  • Adequate vitamin D from sunlight and food. 
  • A healthy diet containing a lot of vitamins and minerals. 
  • Various hormones, including parathyroid hormone, growth hormone, calcitonin, estrogen and testosterone. 
  • Regular weight-bearing exercise.

Bone conditions

Some bone conditions include:

  • Fractures Various types of fractures 
  • Osteoporosis-loss of bone density and strength 
  • Osteomyelitis Bone infection 
  • Osteitis Bone inflammation, such as Paget’s disease of the bones 
  • Acromegaly Excessive growth of bones in the face, hands, and feet. 
  • Abnormal growth - fibrous dysplasia or bone swelling
  • Rickets-Children's growing bones cannot develop due to a lack of vitamin D. 
  • Multiple myeloma-Bone marrow plasma cell carcinoma
  • Bone cancer-Primary bone cancers include osteosarcoma and chondrosarcoma. However, most cancers found in bones have spread from other organs, such as breasts, prostate, lungs or kidneys.

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