Post on 30-Dec-2015
transcript
What is the skeletal system?
Skeletal system consists of bones, teeth, joints, & structures that connect bones to other bones or muscles (ligaments, tendons, & cartilage).
1. Support Many bones provide support, but long bones
especially important Acts as the frame for the rest of the body
long bones in legs help support the trunk other than long bones
the first vertebra supports the skull
2. Protection
Protect vital internal organs skull ->the brain rib cage ->heart, lungs, & abdominal organs
3. Movement Combination w/muscular system, the
skeletal system aids in movement Skeletal muscles are attached to bones by
tendons that act as a lever to move bones.
4. Mineral Storage Outer layers of bony tissues are used for the
storage of minerals (primarily calcium and phosphorus)
5. Blood Cell Formation & Energy Storage
Inner core of bone ->bone marrow Red marrow is a major site of blood cell & platelet
formation. Yellow marrow ->long bones & other mature
bones Yellow marrow consists mostly of fat & serves as
an energy reserve.
What is the purpose? Why is it important? Provides frame and support
Aids movementProtects vital organsMineral storageBlood cell formation
3 cell types found in bones 1. Osteoblasts form a bone structure by secreting
collagen, become enclosed in the matrix, & develop into osteocytes. (BUILD NEW BONE)
2. Osteocytes - exchange of nutrients & wastes with blood (SITE OF CYTE EXCHANGE)
3. Osteoclasts secrete enzymes that digest bone. Bone is a living tissue that is continually remodeled in
response to the body’s need for calcium Osteoclasts are important in the development, growth,
maintenance, & repair of bone (CLASH to break DOWN OLD BONE)
Short bone – cube shaped, (think complex joins like the hock or knee) i.e. carpus and tarsus
Flat bone – plate of bone, (think thin and curved to protect organs) i.e. scapula, rib, skull
Irregular bone – complex shaped attached to muscles, i.e. vertebrae
Long bone – bone is longer that it is wide, i.e. femur, tibia, humerus, etc. (think legs/support)
NOT AS COMMON IN ANIMALS EXCEPT IN PAWS/HANDS Sesamoid – small, seed-shaped bone, i.e. proximal and
distal sesamoids, patella
TYPES OF BONE
How are bones classified? Long bones – femur Short bones – knee Flat bones – ribs, scapula Irregular bones – vertebrae Sesamoid bones –knee cap