Bones & Muscles

How many bones How many bones does the human does the human skeleton contain?skeleton contain?

206

Functions of the skeletal system

Give shape & support Protect internal organs Moves muscles Form blood cells Store calcium and phosphorous

Periosteum: soft, thin, covers and protects the bone

Compact Bone: Hard, outer surface. Can heal itself when broken

Spongy Bone: Porous, contains blood vessels, nerves

Marrow: manufactures red blood cells

Bone Cross Section

Skeletal System

is divided into

two parts

Axial Skeleton Skull (protects

the brain). Ribs ( protect

lungs, and heart).

Spinal column (houses and protects the spinal cord).

Appendicular Skeleton

Legs Pelvis Arms Shoulders

Types of Joints Immovable

Skull Pelvis

Moveable Pivot Ball & socket Hinge Gliding

http://www.nhfyouthworld.org/junior/mayjun/skeleton.jpg

Types of Joints

•Ball and Socket Joint

•Bone with a rounded end that fits into a cuplike cavity on another bone

http://www.shockfamily.net/skeleton/JOINTS.HTML

Ball & Socket: Shoulders and Hips

Allows arms and hips to move in any direction

Can move in a full 360 degrees

Types of Joints

• Pivot Joint

•One bone rotates in a ring of another bone that does not move

http://www.funhousefilms.com/b-pivot2.jpg

Pivot Joints: First two neck vertebrae & joint beneath elbow

Moves in a semicircle motion by twisting against each other

Types of Joints

http://www.shockfamily.net/skeleton/JOINTS.HTML

•Hinge Joint

•Back-and-forth movement like hinges on a door

Hinged: Elbows & Knees

Move like hinges on a door

Limited movement

Can only swing back and forth

Type of Joints

http://www.shockfamily.net/skeleton/JOINTS.HTML

•Gliding Joint

•One part of a bone slides over another bone

Gliding Joints: Spine, Wrists, Ankles

Slide against each other in a gliding motion

Gives your wrists and ankles lots of freedom

Immoveable joints are located in the skull and pelvis.

http://www.lifesci.utexas.edu/faculty/sjasper/images/john21.19.jpg

http://www.bio.psu.edu/

http://www.bmb.psu.edu/courses/bisci004a/tissues/skeletal.jpg

http://www.bio.psu.edu/

http://www.sc.edu/union/Sears/AnimalTissue/im.tissueCardiac.jpg

http://www.bio.psu.edu/

http://www.bmb.psu.edu

How do muscles work

http://www.sirinet.net/~jgjohnso/muscle.html

Muscle Fiber

Muscle

Myofibril

Inside a Muscle

http://www.cytochemistry.net/microanatomy/muscle/smooth1.jpg