What are bones?
A: A bone is a rigid organ that constitutes part of the skeleton in most vertebrate animals.
What do bones do?
A: They protect the various other organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, and enable mobility.
Bones come in a variety of what?
A: Shapes and sizes and have a complex internal and external structure.
They are lightweight yet what?
A: Strong and hard and serve multiple functions.
Bone tissue (osseous tissue) is hard tissue, a type of
A: Connective tissue.
It has a honeycomb-like matrix internally, which helps
to give the bone what?
Bone tissue is made up of different types of what?
A: Bone cells.
Osteoblasts and osteocytes are involved in what?
A: The formation and mineralization of bone.
What are osteoclasts involved in?
A: The resorption of bone tissue.
Other types of tissue found in bones include what?
A: Bone marrow, endosteum, periosteum, nerves, blood vessels and cartilage.
In the human body at birth, there are approximately how
many bones present?
Many of these fuse together during development, leaving
a total of how many separate bones in the adult?
A: 206, not counting numerous small sesamoid bones.
What is the largest bone in the body?
A: The femur or thigh-bone.
What is the smallest?
A: The stapes in the middle ear.
Bone is not uniformly solid, but consists of what?
A: A flexible matrix (about 30%) and bound minerals (about 70%) which are intricately woven and endlessly remodeled by a group of specialized bone cells.
Bone is actively constructed and remodeled throughout
life by special bone cells known as what?
A: Osteoblasts and osteoclasts.
Within any single bone, the tissue is woven into what
two main patterns?
A: Cortical and cancellous bone.
Each with different what?
A: Appearance and characteristics.
What is the hard outer layer of bones composed of?
A: Cortical bone, which is also called compact bone as it is much denser than cancellous bone.
It forms what?
A: The hard exterior (cortex) of bones.
The cortical bone gives bone it’s what?
A: Smooth, white, and solid appearance, and accounts for 80% of the total bone mass of an adult human skeleton.
What is cancellous bone, also called trabecular or
A: The internal tissue of the skeletal bone and is an open cell porous network that follows the material properties of bio foams.
Cancellous bone has a higher what than cortical bone?
A: Surface-area-to-volume ratio and it is less dense.
The greater surface area also makes it suitable for
metabolic activities such as what?
A: The exchange of calcium ions.
Cancellous bone is typically found where?
A: At the ends of long bones, near joints and in the interior of vertebrae.
Cancellous bone is highly vascular and often contains what?
A: Red bone marrow where hematopoiesis, the production of blood cells, occurs.