( NURADILA AHIRAH BINTI LOKMAN – 5 GASTISIA)-
The answer was sent to me Via gmail on the 15th March 2011.
Qs: Explain how the bones, skeletal muscles, tendons and joints bring out movement in the arm or leg.
The skeletal muscles are made up of bundles of muscles fibres. These muscles are attached to the bones of the skeleton to effect movement. The skeletal muscles are not attached directly to the bones. They are attached to at least two bones across joints through the tendons. The bones of the skeleton to which the muscles are attached operate as levers. Skeletal muscles produce movements by exerting the force to pull on the tendons which are attached to bones. All skeletal muscles act as antagonistic pairs. The movement of forelimb is brought about by the contraction and relaxation of a pair of antagonistic muscles, which is called the biceps and triceps. Tendons are tough, strong and inelastic strands of dense connective tissues made up of fibres. Tendons join skeletal muscles to the bone. Ligaments are connective tissues which are flexible, strong and elastic. This allows two bones to be held together and permits limited movement but at the same time, ensures that bones do not become dislocated. Since muscles can only contract, at least two muscles must be used to move a bone in a position and back again. Movements of the body are brought about by the contraction of pairs of antagonistic muscles. Energy for this contraction comes from ATP produced by the mitochondria in the muscles. Muscles which contract when receiving impulses from the brain are voluntary muscles.
My comment: Your answer has covered points on bones, skeletal muscles, tendon and joints. Maximum mark is 10..So you scored 10/10 Congratulation J
Salam, what a good effort! Very lucky having those students... =)
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