Adding _____ to Drinking Water Is a Common Practice in Many

question 17

Multiple Choice

Adding _____ to drinking water is a common practice in many cities, meant to strengthen tooth enamel and decrease dental cavities.

• A) iodine
• B) fluorine
• C) zinc
• D) iron
• E) oxygen

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Definitions:

Z Line (Disc)

A key component in skeletal muscle fibers that anchors the actin filaments and marks the boundary between sarcomeres.

Motor Unit

A single motor neuron and all the muscle fibers it innervates, functioning as a single operational unit in muscle contraction.

Neuron

A specialized cell transmitting nerve impulses; a nerve cell.

Muscle Fiber

A single muscle cell, known for its long, cylindrical shape and role in contracting to facilitate body movement.