Exclusively breastfed babies do not require additional water even when it is very hot outside, as long as baby is allowed to nurse as needed. Even in extremely hot, dry weather your baby can get all the liquids needed via breastmilk.
Smooth muscles contract very slowly, whereas skeletal muscles can contract at different rates. Skeletal muscles can be composed of fast-contracting fibers, slow-contracting fibers or a mixture of both.
Types of Smooth Muscle. Single-unit (unitary) smooth muscle, called visceral muscle, is the most common type of smooth muscle. It contracts rhythmically as a unit, is electrically coupled by gap junctions, and exhibits spontaneous action potentials.mooth muscle cells are small, spindle-shaped cells with one central nucleus, and lack the coarse connective tissue coverings of skeletal muscle. Smooth muscle cells are usually arranged into sheets of opposing fibers, forming a longitudinal layer and a circular layer.