Skeletal System

Skeletal System Humor

What is the job of the skeletal system? The skeleton has five major functions: 1) Provides shape and support. 2) With the muscular systems allows you to move. 3) Protects the soft parts of your body. (Brains, heart, lungs, etc.) 4) Bone marrow makes red blood cells. 5) Bones stores minerals until our body needs them.

1. Provides Shape and Support Legs bones support your body Mandible supports your teeth Muscles are attached to bones An adult human has 206 bones in their body. When a human baby is born they have about 300 bones. What happens to them?

2. Enables you to move The skeletal system cannot move on its own, it needs help from the muscular system. The muscles pull on the bones to make them move.

3. Protects your organs The skeleton also protects your internal organs. Examples: Your rib cage protects your heart, lungs and stomach. Your skull protects your brain.

Your eyes are protected by the eye sockets. Copyright © 2010 Ryan P. Murphy

Your brain is protected by the skull case Copyright © 2010 Ryan P. Murphy

Traumatic brain injury (TBI) A blow to the head that disrupts normal brain function. A mild blow to the head can result in being knocked unconscious. A water barrier is between the skull and brain that also protects it. (skull demo) Copyright © 2010 Ryan P. Murphy

Helmets can help prevent serious brain injury. Wear them! Copyright © 2010 Ryan P. Murphy

Helmets can help prevent serious brain injury. Wear them! Copyright © 2010 Ryan P. Murphy

4. Produces blood cells The bones produce blood cells for the body in the bone marrow. Two types of marrow Red - makes more red blood cells (which carry oxygen), white blood cells (which fight infection), and platelets (that stop bleeding). Yellow - stores fat and can serve as an energy reserve

An average of 2.6 million red blood cells are produced each second by the bone marrow to replace those worn out and destroyed by the liver. Copyright © 2010 Ryan P. Murphy

5. Stores minerals Bones are also a storage unit for certain minerals. Calcium and phosphorus are stored within the bones. The bones release these minerals as they are needed.

Levels of Organization – Skeletal System Cell – Bone cells, cartilage cells, blood cells, adipose (fat) cells, neurons (nerve cells) Tissue –cartilage, connective tissues, epithelial tissues, blood-forming tissues, adipose tissue, and nervous tissue Organ – Bones Organ System – Skeletal System Organism – individual animals

Bones Song Bone tissue is a type of connective tissue that contains lots of calcium and phosphorous salts. About 25% of bone tissue is water, another 25% is made up of protein fibers like collagen. The other 50% of bone tissue is a mixture of mineral salts, primarily calcium and phosphorous.

Layers of the Bone Bones are complex living structures that undergo growth and development. Only 20% of a human’s body weight is from their bones. Bones are light weight but can withstand a lot of pressure. Bones are alive! They can grow and repair after a break.

Layers of the Bone

Outer Layer Periosteum - the fibrous membrane of connective tissue that snugly covers most bones Its main function is to provide nourishment and sensation to the bone by providing the blood supply. 

Compact (Cortical) Bone The compact bone is one of the three layers of a bone. It is a dense, rigid bone. It is shaped like a cylinder and is so hard that surgeons must use a saw to cut through it. This dense layer supports the weight of the body and is made up of mostly calcium and minerals.

Spongy (Trabecular) Bone Spongy (Trabecular) bone comprises the majority of interior long bone tissue, in addition to that of the hip and vertebrae. It is found at the end of the bones. It looks like a sponge with many small spaces within it. It is very light.

Bird bones have air spaces in them so they are light weight. Why does a bird need light weight bones? Copyright © 2010 Ryan P. Murphy

What animal is this? Copyright © 2010 Ryan P. Murphy

What animal is this? Copyright © 2010 Ryan P. Murphy

What animal is this? Copyright © 2010 Ryan P. Murphy

An anteater. Copyright © 2010 Ryan P. Murphy

What animal is this?

Answer! Ray / Manta Ray Sharks and rays do not have bones but have cartilage instead. Copyright © 2010 Ryan P. Murphy

Joints Joints occur where two bones meet. They make the skeleton flexible — without them, movement would be impossible. There are 360 joints in the human body. A joint can be: Movable- joints that can move Immovable- joints that can’t move

Movable Joints of the skeleton The skeleton has six different types of movable joints. Each one moves in a different way. 1) Plane or Gliding joint 2) Hinge joint 3) Ball and socket joint 4) Saddle joint 5) Pivot joint 6) Ellipsoid joint

How are bones held together? Bones are held together by ligaments. Ligaments are long, fibrous straps that fasten bones together.

Ligaments Ligaments Ligaments- strong connective tissue that holds bones in line and in place. Ligaments link bone to bone. Warning! Graphic picture next.

How are muscles attached to bones? Tendons Tendons attach muscles to bones. They are made of strong connective tissue that does not break when pulled.

Cartilage Cartilage Knee Cartilage Cartilage is flexible rubber tissue that cushions and protects the bones where they meet and rub against each other in a joint. Cartilage is found at the ends of bones. Feel the tip of your nose or your ear. They are made of cartilage.

Skeletal System Rap http://www.youtube.com/watch?v=aRXv3qOl8-4