NEET BIOLOGY

Detailed explanation-1: -Smooth muscle is an involuntary non-striated muscle, so-called because it has no sarcomeres and therefore no striations (bands or stripes). It is divided into two subgroups, single-unit and multiunit smooth muscle. Within single-unit muscle, the whole bundle or sheet of smooth muscle cells contracts as a syncytium.

Detailed explanation-2: -Smooth muscle cells are spindle shaped, have a single, centrally located nucleus, and lack striations. They are called involuntary muscles. Cardiac muscle has branching fibers, one nucleus per cell, striations, and intercalated disks.

Detailed explanation-3: -At a cellular level, smooth muscle functions as an involuntary non-striated muscle. Smooth muscle contains thick and thin filaments that do not arrange into sarcomeres, resulting in a non-striated pattern.

Detailed explanation-4: -An example of involuntary muscle movement controlled by smooth muscles is peristalsis, or the contraction of digestive muscles throughout the organs and from one organ to another.

Detailed explanation-5: -Smooth muscle can be found in all the organ systems below: Gastrointestinal tract. Cardiovascular: Blood vessel and lymphatic vessels. Renal: Urinary bladder.