MICROANATOMY

Detailed explanation-1: -Smooth Muscle The non-striated (smooth) muscle cell is spindle-shaped and has one central nucleus. Smooth muscle contracts slowly and rhythmically.

Detailed explanation-2: -The tension generated is relative to the amount of calcium concentration within the cell. ATPase activity is much lower in smooth muscle than it is in skeletal muscle. This factor leads to a much slower cycling speed of smooth muscle.

Detailed explanation-3: -When made to contract, the smooth muscle cells shorten, thereby propelling the luminal contents of the organ, or the cell shortening varies the diameter of a tube to regulate the flow of its contents. There are also bundles of smooth muscle cells attached to the hairs of the skin and to the iris and lens of the eye.

Detailed explanation-4: -In general, smooth muscles contract more slowly than do skeletal muscle fibers and maintain the contraction for longer periods of time. Smooth muscles can be divided into phasic muscles which contract more rapidly and tonic muscles which contract slowly and maintain tension for long periods of time.