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Arm - Upper Limb

The upper limb includes the:
humerus (arm)

• radius and ulna (forearm)

bones of the hand: carpals (wrist), metacarpals (palm) and phalanges (fingers and thumb).

The humerus is a long bone connected to a ball and socket joint in the shoulder and a hinge joint at the elbow.
The radius is on the thumb-side of the forearm.
The ulna is on the pinky side of the forearm and includes the elbow (olecranon process).
The hand has 27 bones; 8 carpals in the wrist, 5 metcarpals in the palm and 14 phalanges (each finger has 3, except the thumb, which has 2.)

The arm and forearm bend at the elbow in a hinge joint, which is not as flexible as the shoulder joint, but is much more stable. The hand with its many joints is made to be flexible and agile. It can grasp and lift a heavy suitcase or careful pick up a pin. The upper limb is made to do both and everything in between.

*See the PDF below for an Upper Limb Labeling Page.

The Upper Limb (Arm)

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Next Generation Science Standards (NGSS)

Grade 6-8 - MS-LS1 From Molecules to Organisms: Structures and Processes

LS1.A: Structure and Function
• All living things are made up of cells, which is the smallest unit that can be said to be alive. An organism may consist of one single cell (unicellular) or many different numbers and types of cells (multicellular). (MS-LS1-1)
• Within cells, special structures are responsible for particular functions, and the cell membrane forms the boundary that controls what enters and leaves the cell. (MS-LS1-2)
• In multicellular organisms, the body is a system of multiple interacting subsystems. These subsystems are groups of cells that work together to form tissues and organs that are specialized for particular body functions. (MS-LS1-3)

Exploringnature.org has more than 2,000 illustrated animals. Read about them, color them, label them, learn to draw them.