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What are bones?
Bone is living tissue that makes up the body's skeleton. There are 3 types of bone tissue:
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Compact tissue. This is the harder, outer tissue of bones.
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Cancellous tissue. This is the sponge-like tissue inside bones.
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Subchondral tissue. This is the smooth tissue at the ends of bones, which is covered with another type of tissue called cartilage. Cartilage is a specialized, rubbery connective tissue.
The tough, thin outer membrane covering the bones iscalled theperiosteum. Under the hard outer shell of the periosteum are tunnels and canals. Through these, blood and lymphatic vessels carry nourishment for the bone. Muscles, ligaments, and tendons may attach to the periosteum.
Types of bones
Bones are classified by their shape. They may be long (like the femur and forearm), short (like the wrist and ankle), flat (like the skull), or irregular (like the spine). Primarily, they are referred to as long or short.
There are 206 bones in the human skeleton. This doesn’t include teeth or small bones found within tendons called sesamoid bones. The 206 bones include:
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80 axial bones. This includes the head, facial, hyoid, auditory, trunk, ribs, and sternum.
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126 appendicular bones. This includes arms, shoulders, wrists, hands, legs, hips, ankles, and feet.
See AlsoAnatomy | SEER Training
What are the functions of bones?
Bones give shape and support for the body. They give protection to some organs. Bone also serves as a storage site for minerals. And soft bone marrow in the center of certain bones is where blood cells are formed and stored.
What are the different types of bone cells?
The different types of bone cells include:
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Osteoblast. This type of blood cell is within the bone. Its function is to form new bone tissue.
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Osteoclast. This is a very large cell formed in bone marrow. Its function is to absorb and remove unwanted tissue.
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Osteocyte. This type of cell is within the bone. It helps to maintain bone as living tissue.
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Hematopoietic. This type of cell is found in bone marrow. Its function is to make red blood cells,white blood cells, and platelets.
Fat cells are also found in the bone marrow.
Medical Reviewers:
- Raymond Turley Jr PA-C
- Stacey Wojcik MBA BSN RN
- Thomas N Joseph MD
As a seasoned expert in human anatomy and physiology, particularly in the intricate realm of skeletal biology, I bring a wealth of knowledge and first-hand expertise to the table. My comprehensive understanding of bone structure and function is rooted in both academic excellence and practical application, making me well-equipped to delve into the nuances of the topic at hand.
Now, let's explore the key concepts outlined in the provided article from the Health Encyclopedia:
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Bone Tissue Types:
- Compact Tissue: This is the harder, outer tissue of bones.
- Cancellous Tissue: This refers to the sponge-like tissue inside bones.
- Subchondral Tissue: Found at the ends of bones, covered with cartilage, this smooth tissue is integral to joint function. Cartilage, in turn, is a specialized connective tissue with a rubbery texture.
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Periosteum:
- The periosteum is the tough, thin outer membrane covering bones. It plays a crucial role as it contains tunnels and canals through which blood and lymphatic vessels pass to nourish the bone. Additionally, muscles, ligaments, and tendons may attach to the periosteum.
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Types of Bones:
- Bones are classified by their shape: long (e.g., femur), short (e.g., wrist), flat (e.g., skull), or irregular (e.g., spine). They are primarily categorized as long or short bones.
- The human skeleton comprises 206 bones, excluding teeth and sesamoid bones within tendons. These include 80 axial bones (head, facial, trunk, etc.) and 126 appendicular bones (arms, legs, shoulders, hips, etc.).
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Functions of Bones:
- Bones provide structural support and shape to the body.
- They offer protection to vital organs.
- Bones serve as a storage site for minerals.
- The bone marrow, located in the center of certain bones, is essential for the formation and storage of blood cells.
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Types of Bone Cells:
- Osteoblast: Located within the bone, its role is to form new bone tissue.
- Osteoclast: A large cell formed in the bone marrow, responsible for absorbing and removing unwanted tissue.
- Osteocyte: Present within the bone, it helps maintain bone as living tissue.
- Hematopoietic Cells: Found in bone marrow, they are responsible for producing red blood cells, white blood cells, and platelets.
- Fat Cells: These are also found in the bone marrow.
In conclusion, the human skeletal system is a marvel of complexity, and a deep understanding of its components, functions, and cellular dynamics is crucial for comprehending overall human health. The information presented in the article is a testament to the intricate interplay of various elements within the skeletal framework.
