Skeletal System Notes

• What do all Vertebrates have?

  • An endoskeleton (inside)

    • helps retain shape and form

• What’s the skeletal system composed of?

  • all of the bones and joints in the body

  What are the functions of an Endoskeleton?

  1. Provides support and form

  2. A lever system from attachments of muscles

  3. Protects inner organs

  4. Stores minerals (calcium, phosphorus)

  5. Produce RBC’s and WBC’s in Red Marrow

  6. Stores fat in Yellow Marrow

What does cartilage do?

• cushions and protects joints and allows them to move

• Changes to bone as Calcium and phosphorus are added during growth

Structure of Bones Notes

• What are bones made up of?

  • Osteocytes, Calcium Salts, Haversian Canals, Periosteum

• WHAT ARE THESE?

  • Osteocytes- regulate the amount of calcium stored and released from bones

  • Calcium Salts- like a shell that gives bone strength and protection

  • Haversian Canals- a passage that runs through bones and contains blood vessels and nerves

    • carries oxygen and nutrients to bones & removes wastes

  • Periosteum- tough membrane on the OUTER surface of bones

    1. contains blood vessels and nerves that enter the bone

    2. Makes new bone for growth and repair

    3. Site for muscle and bone attachments

• What are the Types of Bones?

  1. Compact Bone

     1. A thick layer beneath the periosteum

     2. Very dense, strong

     3. Found in the outer layer and ends of the bone

  2. Spongy Bone

     1. Beneath the layer of compact bone

        Is not soft but spongy.

     2. Very strong

     3. Contains bone marrow

  • What does the spongy bone add ?

    • adds strength without adding mass

Bone Marrow Notes

Axial Skeleton Notes

• Skull