the skeletal system 6 th grade. are bones in your body alive? what are they made of? yes! the bones...
TRANSCRIPT
Are bones in your body alive? What are they made of?
• YES!• The bones in your body are alive – Made of tissues that have cells that take in
nutrients and use energy
Reason #2:
• PROTECT your internal organs– Ex. skull protects your brain – Ex. ribs surround the heart and lungs
Reason #5:
• Large quantities of CALCIUM and PHOSPHORUS are stored in the skeleton for later use these make bones hard
Under the periosteum, what are the 2 types of bone tissue?
• Compact Bone Tissue:
• Spongy Bone Tissue:
Compact Bone Tissue
– HARD structure that gives bones strength– Contains deposits of calcium and phosphorus– Bone cells and blood vessels are found in this layer--keeps the bone from being too rigid, brittle or easy to break--even though it is hard, it is still ALIVE
Spongy Bone Tissue
• Located at the end of long bones
• Has many small open spaces to make your bones lightweight
The cavities and spaces in spongy bone are filled with MARROW
– Yellow marrow: composed of fat cells– Red marrow: produces red blood cells at a rate of
2-3 million cells per SECOND
What is Cartilage?
• A smooth, slippery, thick layer of tissue that covers the ends of bones
• Flexible, important to joints because it reduces friction so that bones to not rub together
• People with damaged cartilage have pain when they move
Bone Cells
• Osteoblasts: build up bone by depositing calcium and phosphorus to make them strong
• Osteoclasts: break bone down, releasing calcium and phosphorus into the bloodstream– Your body needs these elements to move your
muscles
What are joints? What are ligaments?
• Joints: Any place where 2 or more bones come together they do not rub against each other
• Ligaments: a tough band of tissue that hold joints in place
The joint is the place where the 2 bones come together, the cartilage is the layer of tissue between the bones, and the ligament is a tough layer and of tissue holding
the bones in place.
Ligaments vs. Tendons
• Ligaments connect BONE to BONE
• Tendons connect BONE to MUSCLE
https://www.youtube.com/watch?v=PdJ5QDkqG2g