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Under the skin of the hands, you will find the body’s most sophistica­ted network of bones and joints.

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Do colours influence our mood and do all flies lay on their backs when they die?

A hand is a fine-tuned gripping device and an important sensory organ made up of a clever system of unbroken bones, muscles, joints, ligaments, tendons, nerves, and blood vessels. The bones and muscles cooperate to provide the hand with strength, the joints ensure mobility, and the nerves are responsibl­e for the sense of touch. The powerful forearm muscles bend fingers and wrists by pulling at the bones of the hand via long, slim tendons. The hand itself contains a number of small muscles, which in complex interactio­n take care of the fingers’ ultrafine precision motions such as controllin­g the direction of a pen or threading a needle.

The hand itself consists of the carpus, the metacarpus, and the fingers. The carpus is a mosaic of eight bones located in two rows that are closely linked by tight ligaments. One bone for every finger make up the metacarpus. The thumb's metacarpal bone is shorter than that of the four other fingers, but much more flexible in the basic joint. This ensures that the thumb can be moved in front of the palm of the hand, allowing the hand to grip a tool, rope, etc.

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