: Skeletal muscles (striated) are responsible for voluntary movements, while smooth muscles control internal organs and are involuntary.

: Bones are made of organic substances (which provide flexibility) and inorganic minerals like calcium (which provide hardness).

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: A lack of physical activity can lead to weakened muscles and cardiovascular issues.

: Muscle fatigue is caused by the accumulation of metabolic waste (like lactic acid) and the depletion of energy stores during prolonged physical activity. Health and Posture

: Maintaining correct posture is essential during childhood and adolescence while bones are still growing to prevent conditions like scoliosis.

: Functions as a support frame, protects internal organs, and allows for movement. It consists of the skull, spinal column, rib cage, and the skeleton of the upper and lower limbs.