7th Grade Study Guide for Skeletal System

Cranium

Cranium

Skull

Radius

Main forearm bone

Ulna

Lesser forearm bone

zygoma

Cheekbone

Humerus

upper arm bone

Maxilla

upper jaw

Mandible

lower jaw

Clavicle

collarbone

Scapula

shoulder blade

Sternum

Breastbone

Ribs

Vertebral Column

Spine

Pelvis

Hipbone

Femur

Upper leg bone

Patella

kneecap

Tibia

shin bone

Fibula

calf bone

Tarsals

Ankle bones

Metatarsals

Foot bones

Phalanges

Toe and finger bones

Carpals

wrist bone

Metacarpals

hand bones

Tendons

connects muscles to bone

Ligaments

connects bone to bone

Cartilage

cushion between bones at a join and protects the bone

The Role of the Bones

1. Give support to your body

2. Keep storage

3. Enable movement

4. Blood Cell Formation

Ball-and-Socket Joints

Ball-shaped end of one bone fits into a cup shaped socket/allows widest range of motion such as rotation

Hinge Joint

Allows movement in a single plane/Formed when a convex projection on one bone fits in a concave depression in another such as your knee

Pivot Joint

Is Formed when rounded or conical surfaces of one bone fit into a ring of one or tendon allowing rotation/allows freedom of movement between ball and socket and hing joining/found in wrists, ankle and neck

Sliding Joint

Is formed when flat or slightly flat surfaces move against each other allowing sliding or twisting without any circular movement/ in the carpals, tarsals, vertebrae

Fixed Joint

Do not allow movement and are extremely strong such as the joints of the skull/held together with ligaments and when ligament is stretched too far, it becomes strained/will heal over time

Axial Skeleton

Made up of 80 bones, contains the vertebral column, rib cage, and skull, enables upright posture

Appendicular Skeleton

Made up of 126 bones, contains the pectoral girdles, upper limbs, pelvic girdle, and lower limbs, enables movement

What are the components of the human skeleton

Bones, tendons, ligaments, muscles

The purpose of cartilage

The purpose of cartilage is to reduce the friction between bones, and absorb shock. 

The primary function of the muscle system

3 types of muscles

Cardiac muscle

smooth muscle

skeletal muscle