: Bones are made of organic substances (which provide flexibility) and inorganic minerals like calcium (which provide hardness).
: A lack of physical activity can lead to weakened muscles and cardiovascular issues. gdz po biologii 8 klass r.t opora i dvizhenie onlain sonin
: 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. : Bones are made of organic substances (which
: 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 It consists of the skull, spinal column, rib
: Maintaining correct posture is essential during childhood and adolescence while bones are still growing to prevent conditions like scoliosis.
: Skeletal muscles (striated) are responsible for voluntary movements, while smooth muscles control internal organs and are involuntary.