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The skeletal system is made up of the bones that give structure to the human body. Bones protect and support vital organs and work with muscles to help the body move. Bone marrow is the soft inner part of many bones of the body.
Some of the bones in the skeletal system include the:
The spine is made up of many vertebrae and provides the main central support for the human body. It also protects the spinal cord (nerves that go from the brain to other parts of the body) and allows flexible movement. There are 4 main sections to the spine:
The thorax (chest) includes a number of different bones. These include:
The arms (not including the hands) consist of three bones:
The pelvis, or hip bones, has 3 major parts:
The pelvis connects the spine to the lower legs and helps support the upper body
The legs (not including the ankles or feet) have three main bones:
Bone marrow is the soft, spongy inner part of many bones. In some bones the marrow is only fatty tissue. In other bones it contains blood-forming cells. These cells make new red blood cells, white blood cells, and blood platelets.
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
Last Revised: December 13, 2022
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