Skeletal System,Muscular System,
&The Skin
We are born with over 300 bones. As we grow, some of these bones fuse
together. As adults we have
only 206 bones!
Bone Facts:Function - Your bones manufacture red blood cells and store useful minerals.
Bones are held together by muscles that allow them to move.
Some bones are joined by flexible parts called joints.
Ligaments – connective tissue which holds bone in moveable joints. (A sprain is when ligaments are stretched too far.)
The smallest bones are in your ear.
The largest bone, the femur, is found in your thigh.
• The bones in your body are very much alive.
• Each is a living organ made of several different tissues.
• Like all the other living tissues in your body, bone tissue is made of cells that take in nutrients and use energy.
• Bone cells have the same needs as other body cells.
Living Bones
Functions of Your
Skeletal System
1.The skeleton gives shape and support to your body.
2.Bones protect your internal organs.
3.Major muscles are attached to bone and help them move.
4.Blood cells are made in the bone marrow.
Functions of Your Skeletal System
5.Calcium and phosphorous are stored in the skeleton for later use.
Jaw Bone
Tail Bone
Skull – protects the brain.
• Bones have bumps, edges, round ends, rough spots, and many pits and holes.
• Muscles and ligaments attach to some of the bumps and pits.
Bone Structure
• In your body, blood vessels and nerves enter and leave through the holes.
Define:
•Joint•Cartilage•Ligament
• Joint - Anyplace where two or more
bones come together. • Cartilage - Slick,
smooth, slippery,
flexible tissue that
makes movement
easier .• Ligaments - A tough band of
tissue that is attached to bones.
• Cartilage – a connective tissue that is more flexible than bone.
•It reduces friction that would be caused by bones rubbing together.
• Joints are broadly classified as immovable or movable.
Immovable Joints
• An immovable joint allows little or no movement.
Ex. skull and pelvis
Movable Joints – Describe each:
•Pivot Joint•Ball and Socket Joint•Hinge Joint•Gliding Joint
• pivot joint - one bone rotates in a ring of another bone that doesn’t move.
Movable Joints
• Ex. Forearm
• ball-and-socket joint consists of a round bone fitting into a cup-like bone.
Movable Joints
• Ex. Shoulder & Hip
• hinge joint-back-and-forth movement like hinges on a door.
Movable Joints
• Ex. Knee, elbows, toes, & fingers
• gliding joint - a bone slides over another bone in a back-and-forth motion.
• Ex. Wrists, ankles, and between vertebrae
Movable Joints
Your rib cage is made up of 12 vertebrae, 24 ribs and a breastbone in three parts. It protects your heart and lungs from knocks and bumps.
Look, Mom, no hands....no feet!!
Over half your bones are found in your hands and feet. There are 26 bones in each foot and 27 in each hand.
Skeletal System
OsteoporosisOsteoporosis – mineral loss in bones where they become weak
and break easily.
Scoliosis
Interactivehttp://www.ehc.com/vbody.asp
-Possible causes:congenital spine deformities, genetic conditions, neuromuscular problems, etc.
-Over 80% of scoliosis cases, have no known cause and are found in otherwise healthy people.
MRI’s soft tissue X Rays bone tissue
“I’m just “bigged boned”.” (??)
Movable Joints –
•Pivot Joint - Forearm
•Ball and Socket Joint – Hip / Shoulder
•Hinge Joint – Fingers, elbow, knees and toes
•Gliding Joint – Neck vertebra & down spine, wrist, ankle
Human Skeleton 9
KidsHealth
Muscles & the Facts
• Goose Bumps – caused by smooth muscles, the tiniest muscles.
• 100 muscles in your face
• 17 muscles used to smile • 43 muscles to frown!!!!!
FACTOID• Spasm- strong muscle
contractions when enough food & oxygen aren’t available.
Movement of the Human Body
• Muscle - an organ that can relax, contract, and provide the force to move your body parts.
What is the difference between voluntary and involuntary muscles?
Involuntary Muscles – muscles you can’t control consciously.
• work all day long• Ex: circulatory and digestive muscles.
Voluntary muscles - Muscles that you are
able to control .
Parts of the Muscular System
Smooth Muscles
Cardiac Muscles
Skeletal Muscles
Tendons
Define each part of the Muscular System.
Cardiac muscles Involuntary muscle that
controls the heart.• Skeletal muscles
– Voluntary muscles that make us move
– THEY WORK IN PAIRS. Muscles always pull. They never push.
Smooth muscles Involuntary muscles in organs and body systems.
Types of Muscles:
• the muscles that move bones
• muscles that work in pairs
Skeletal MusclesSkeletal Muscles
•Tendons - Tissues that attach muscle to bones to
enable movement .
Walking bobby pin
Cardiac Muscle• Cardiac muscle - found only in the heart.
• This type of muscle contracts about 70 times per minute every day of your life.
Smooth Muscles
• Smooth muscles - found in your organs.
• involuntary muscles that slowly contract and relax. • Internal organs are
made of one or more layers of smooth muscle.
Muscular System
Pushing the Limits 43
What is Skin???
• http://www.wimp.com/whatskin/
Epidermis – Upper layer of thin skin where skin cells die and flake off.
Dermis – Layer of cells below the epidermis where blood vessel and nerve endings are located.
Your Largest Organ
• Your skin is the largest organ of your body.
• Much of the information you receive about your environment comes through your skin.
• You can think of your skin as your largest sense organ.
List the 6 functions of the Integumentary / Skin
System.
Functions of Integumentary / Skin System
• Covers body and prevents water loss.• Protects body from infection or injury.• Regulates body temperature.• Eliminates waste - salt and excess
water.• Gathers information from environment
(Touch, etc.)• Produces Vit. D to help digestive
Skin….Stress….Hormones….Pimples
http://ed.ted.com/lessons/does-stress-cause-pimples-claudia-aguirre
Melanin
• Cells in the epidermis produce the chemical melanin.
• Melanin is a pigment that protects your skin and gives it color.
• The different amounts of melanin produced by cells causes differences in skin color.
Melanin
• When your skin is exposed to ultraviolet rays, melanin production increases and your skin becomes darker.
• Lighter skin tones have less protection from the Sun
• Such skin burns more easily and may be more susceptible to skin cancer.
Skin Cancer• Damaged skin
cells begin to grow and divide uncontrollably.
Squamous Cell – another type of skin cancer.