MP Board · Class 9 · Science · TissuesDescribe the structural features, nuclear nature, and location of Striated, Unstriated, and Cardiac muscle tissues in the human body.
Muscular tissues are responsible for movement in the body and are classified into three types based on structure and control:
-
Striated (Skeletal) Muscles: These muscle cells are long, cylindrical, unbranched, and multinucleate (having many nuclei near the periphery). They display clear alternate light and dark bands (striations) when viewed under a microscope. They are voluntary in nature and are attached to bones, helping in skeletal movement (e.g., muscles of arms and legs).
-
Unstriated (Smooth) Muscles: These cells are long, spindle-shaped (tapering at both ends), unbranched, and uninucleate (having a single central nucleus). They lack striations, giving them a smooth appearance. They are involuntary and line the walls of internal organs such as the stomach, intestine, blood vessels, and iris of the eye.
-
Cardiac Muscles: These cells are short, cylindrical, branched, and uninucleate. They show faint striations and intercalated discs. Present exclusively in the walls of the heart, they are involuntary and show rhythmically continuous contractions throughout life.