Skeletal system - by Elizabeth Tate Is made up of all your bones, cartilage, and joints.


Structure and function
  • The major functions are to make a frame for your body, to movement possible, to protect your internal organs, to create new blood cells, and to store inorganic materials.
    • Such as, calcium, phosphate, magnesium, sodium, potassium, carbohydrates along_bone.jpgnd much more.
  • Epiphysis, are expanded ends of bones that articulates with another bone, usually forming a joint.
  • Diaphysis, are the shafts of the bone.
  • Articular cartilage, or hyaline cartilage, covers the ends of bones.
  • Periosteum is the tough memberane-like covering the entire bone, except for articular cartilage. It connects with tendons and ligaments and froms bone tissues.
  • Types of bone tissue are:
    • Compact bone, which is the wall of the diaphysis, it’s solid, and strong.
    • Spongy bone, which is epidhysis, and is covered by a thin layer of compact bone.
  • Matrix is where the bone cells live, and is composed of collagen and inorganic salts.
  • Osteocytes, are mature bone cells.
  • Osterporosis, is an increase in activity of osteoclast and causes a breakdown of bones and the subsequent fewer minerals in the extra cellular matrix, which makes bones fragile.
  • Endochorndral bones, are all other bones and they start as hyaline cartlage and gradually turn into solid bone through, ossification.
  • Epiphyseal disk, also known as your growth plate, is a band of cartilage between the epiphysis and diaphysis and they increase the length of the bones as cells ossify.
  • There is three types of joints: synarthrotic, amphiarthotic, and diarthrotic.hand.jpg
    • Synarthrotic are unmovable or fixed joints.
    • Amphiarthotic are slightly moveable joints.
    • Diarthrotic are moveable or synovial joints.
  • bone marrow:
    • red marrow: mainly in spongy bone, and it produces red blood cells.
    • yellow marrow: it stores fat and replaces red marrow throught out childhood.
  • You have about 206 bones in your body as an adult and around 300 as a baby.
    Your bones are divided into two main divisions: axial and appendicular.
    • Your axial skeleton is made up of the head, neck, skull, and the trunk of your body.foot.jpg
      • Consisting of, your hyoid bone, vertebral colum, thoracic cage, and sternum.
    • Your appendicular skeleton is made up of the limbs, and bones connecting to the pectoral or pelvic gridles.
      • Pectoral girdle, shoulders, scapula, clavicale, and upper limbs.
      • Pelvic girdle, coxal bones, and lower limb
  • The Skull.
    • Intramembranous bones are broad flat bones of the skull, and they form from membrane-like sheets of connective tissue.
    • bones of the skull:
      • frontal: anterior proption above the eyes.
      • parietal: you have one on each side of your skull, and it is located behind the frontal bone.
      • occipital: forms the back of the skull and the base of the cranium.
      • temporal: forms parts of the sides and the base of the cranium.
      • sphenoid: is wedged between several other bones in antior portion of the cranium.
      • maxillaa: forms upper jaws.
      • mandible: lower jaws, only movable bone of the skull.
      • sygomatic bone: is your cheekbone.cranium_front.jpgcranium_side.jpg

Enzymes and hormomes
  • human growth hormone: affects the growth and development of bones.
  • mineralocorticoids: controls the release of minerals.
  • androgens:are sex horomoes, and they affect the way your bones grown wether it be male or female. affects the pectorial girdle and pectorial girdle.
  • parathyroid & prostaglandin E: stimulate resorption and bone formation.

  • Osteoclast, dissolve bone tissue to release minerals, and this is called resorption.
    • controlls the amount of bone tissue you have.
    • deposits minerals back into bones and the blood.
  • the bone marrow repaces new red blood cells as they are needed.

  • the cells comunicate through gap junctions to controll the bone formation and resorption.
    • Osteoblasts, osteocytes and osteoclasts

it's a really cool video, you don't have to watch if you don't want to.