The Skeletal System Chapter 13 section 2

Functions of the Skeletal System  Provides shape and support  Protects your organs  Allows you to move  Makes blood cells  Stores minerals

Shape and support  Holds up your body  Gives the body shape  The backbone is the center of the skeleton Made of vertebrae Made of vertebrae Vertebrae strung together Vertebrae strung together It adjusts as you bend It adjusts as you bend

Movement and protection  The skeleton allows you to move and protects your organs  Bones are associated with muscles Bones that help you move are long and stick- like (ex. Femur and tibia) Bones that help you move are long and stick- like (ex. Femur and tibia)  Bones protect your body Bones that protect are flattened (ex. Cranium, and sternum) Bones that protect are flattened (ex. Cranium, and sternum)

Mover or protector?

Makes and stores substances  Bone makes blood Blood cells are made in the center of bones Blood cells are made in the center of bones The cells pass into the blood The cells pass into the blood  Bone stores materials like calcium and phosphorus The materials are released into the blood when they are needed The materials are released into the blood when they are needed

Check up Questions List the 5 functions of the skeleton. List the 5 functions of the skeleton. What is the center of the skeleton called? What is the center of the skeleton called? Bones that make you move are ________ Bones that make you move are ________ and _____________. and _____________. Bones that protect are ___________. Bones that protect are ___________. What are the 2 minerals stored in the bone? What are the 2 minerals stored in the bone?

Joints of the Skeleton  Joints join the bones together  Joints allow you to move  There are two kinds of joints Movable Movable Immovable Immovable

Immovable joints  These joints connect bones and don’t allow them to move  They allow for growth

Movable joints  Movable joints also join bones together  Bones in movable joints are held together with ligaments  Movable joints contain cartilage Cartilage is flexible Cartilage is flexible Covers ends of bones and prevents rubbing Covers ends of bones and prevents rubbing  Movable joints contain a fluid The fluid lubricates The fluid lubricates

Joint anatomy

Types of Moveable Joints  Hinge Joint – back and forth movement ( elbow)

Ball and socket – allows greatest range of motion (hip joint) 10/manphys/joints.htm 10/manphys/joints.htm

Pivot joint – one bone to rotate around another (ulna and radius)

Saddle joint – all movement possible

Gliding joint – allows one bone to slide over another (wrist and ankle joint)

Check up Questions What are the 2 functions of joints? What are the 2 functions of joints? What are the 2 types of joints? What are the 2 types of joints? Immoveable joints connect bones Immoveable joints connect bones and don’t allow them to _________. and don’t allow them to _________. Bones with moveable joints are held together with ______________. Bones with moveable joints are held together with ______________. List the different types of moveable joints. List the different types of moveable joints.

Bones – Strong and living  Bones are living  Bones have structure  Bones grow  Bones develop

Bones Structure  Covered with a membrane  Supplied with blood vessels and nerves  The external layer is compact bone  The internal layer is spongy bone  The spaces in the bone are filled with marrow Red marrow – makes blood cells Red marrow – makes blood cells Yellow marrow stores fat for energy Yellow marrow stores fat for energy

Bone Anatomy

Bone strength  Structure makes a bone strong and light  Bone strength allows it to absorb lots of force Strength of bone comes from calcium and phosphorus in the bone Strength of bone comes from calcium and phosphorus in the bone  Bones are light – your skeleton is 20% of your weight

Bone growth  Bones are living – they contain cells and tissues  Bones form new bone as you grow and during life  Bones can heal when they are broken

Bone development  Cartilage often forms bone as you grow  Some cartilage remains in your body

Check up Questions Bones can ______________ a lot of force. Bones can ______________ a lot of force. Bones are ____________ and contain cells and ____________. Bones are ____________ and contain cells and ____________. Bones are ___________.(20% of our body weight) Bones are ___________.(20% of our body weight)

Taking care of your bones Good diet and exercise keep bones healthy  Diet Contains enough calcium and phosphorus Contains enough calcium and phosphorus Calcium from milk and cheeseCalcium from milk and cheese Phosphorus from meat, leafy green veggies, whole grainsPhosphorus from meat, leafy green veggies, whole grains  Exercise During exercise your bones are stressed by supporting your weight and being pulled on by muscles During exercise your bones are stressed by supporting your weight and being pulled on by muscles Stressing bones increases their strength Stressing bones increases their strength

Some Bone Diseases/disorders  Osteoporosis – bones are weak because of calcium loss (old person disease)  Arthritis – joint cartilage is damaged and bone can’t slide  Sprain – Ligament that connect a joint are overstretched or even torn  Achondroplasia – bones cannot grow in length

Osteoporosis

Arthritis

Sprain

Achondroplasia

Check up Questions Your diet should contain ___________ and ______________. Your diet should contain ___________ and ______________. What types of food contain calcium and/or phosphorus? What types of food contain calcium and/or phosphorus? How does exercise keep your bones healthy? How does exercise keep your bones healthy?