Joints (Musculoskeletal System)

Joints

7th Grade Science - Ms. Reid

Vocabulary Review

• Joint - a place where two bones meet

• Ligament - tissue which connects two bones

• Tendon - tissue which connects a muscle to a bone

Multiple Choice

Which pair would be connected by a ligament?

• biceps & triceps

• femur & fibula

• biceps & humerus

• cartilage & scapula

Multiple Choice

Which pair could be connected by a tendon?

• humerus & ulna

• gluteus maximus & abdominals

• ulna & radius

• biceps & scapula

Cartilage

• firm, smooth, white connective tissue

• found at the ends of bones and in between joints

• infants have a lot of cartilage, which is replaced by bone as they grow

Open Ended

Where can you find cartilage in your body? (If you don't know, take a guess!)

Joint Classification

• Immovable (fixed) - cranium

• Slightly movable (cartilaginous) - vertebrae

• Movable (synovial) - hip

types of movable (synovial) joints

Hinge Joints

• allows bones to swing in 1 direction, only

• similar to hinges on a door

• Examples: knee, elbow, finger joints, toe joints, part of ankle

Like doors, hinge joints can move in 1 direction, such as left to right OR up and down.

This is the hinge joint in the knee.

This is the hinge joint in the elbow.

Multiple Select

Hinge joints...

• are found in the elbow

• are the most flexible joint

• can move in one way

• can move in two ways

• are found in the neck

Ball-and-socket Joint

• the most flexible joint

• allows for almost all movement

• ball-like end of a bone fits into a cup-like socket of another

• Examples: shoulder, hip

How a ball-and-socket joint can move

Because it is a ball-and-socket joint, your hip can move in many ways.

Your shoulder can also move up & down, move left & right, twist, and pivot!

Multiple Select

Ball-and-socket joints can...

• move up and down

• move left to right

• twist

• pivot

Pivot Joint

• one bone twists around another

• allows side-to-side or turning movement

• Examples: top vertebrae meeting the cranium (neck)

How a pivot joint moves

The top of the spine meets the cranium in a pivot joint.

Multiple Choice

Which of the following is an example of a hinge joint?

Multiple Choice

Which of the following is an example of a ball-and-socket joint?

• vertebrae

• toe

• shoulder

• knee

Multiple Choice

Which of the following is an example of a pivot joint?