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Quadrupedal Mechanics - Anatomy & Physiology (view source)
Revision as of 01:01, 20 June 2013
, 01:01, 20 June 2013→A muscle either makes movement, or prevents it: Action or heat?
==='''A muscle either makes movement, or prevents it: Action or heat?'''===
==='''A muscle either makes movement, or prevents it: Action or heat?'''===
[[File:QMFig 4.1.png|thumb|'''Fig.4.1 Muscle structure 1''']]
Forces produced within muscles achieve animal posture and motion. A muscle (Fig 4.1 a, b) consists of a large number of fibres (Fig 4.1 c) arranged in such a way that a force is developed between the two ends of the muscle when the fibres are stimulated by electrical impulses coming from nerves. This force may cause movement, but if the force is no greater than opposing forces either within the animal's body (i.e. from antagonist muscles) or acting externally on the animal's body (such as the force of gravity), no movement will result.
Forces produced within muscles achieve animal posture and motion. A muscle (Fig 4.1 a, b) consists of a large number of fibres (Fig 4.1 c) arranged in such a way that a force is developed between the two ends of the muscle when the fibres are stimulated by electrical impulses coming from nerves. This force may cause movement, but if the force is no greater than opposing forces either within the animal's body (i.e. from antagonist muscles) or acting externally on the animal's body (such as the force of gravity), no movement will result.
:::::'''Fig. 4.1 Muscle structure 1'''
:::::'''Fig. 4.1 Muscle structure 1'''
:::::The semitendinosus muscle of a dog, as seen by the unaided eye (a & b), and in transverse section with the light microscope (c).
==='''The contractile proteins of muscle''' ===
==='''The contractile proteins of muscle''' ===