Question

what are the differences and similarities between skeletal and smooth muscle tissue

Answer 1

Similarities: Both are muscle.
Differences: Smooth muscle isn't striated.

Answer 2

Skeletal Muscle Structure.The cells of skeletal muscles are long fiber-like structures. They contain many nuclei and are subdivided into smaller structures called myofibrils. Myofibrils are composed of 2 kinds of myofilaments. The thin filaments are made of 2 strands of the protein actin and one strand of a regulatory protein coiled together. The thick filaments are staggered arrays of myosin molecules.
* Units of organization of skeletal muscle. The filaments are organized into structures called sarcomeres. Sarcomeres are constructed in the following manner:
* Z lines are at the borders of the sarcomere. They align in adjacent myofibrils.
* I bands are areas near the edge of the sarcomere containing only thin filaments.
* A bands are regions where thick and thin filaments overlap and correspond to the length of the thick filaments.
* H zones are areas in the center of the A bands containing only thick filaments.

Cardiac Muscle. in vertebrates is only found in the heart. It is striated. Muscles cells are branched, and the junctions between the cells contain intercalated discs that electrically connects all heart muscle cells, allowing coordinated action. Cells can also generate their own action potential.


Smooth Muscle. lack striations and contain less myosin; the myosin is not associated with specific actin strands. Contractions are slow but there is a greater range of control. Calcium must enter the cell through the plasma membrane during an action potential. Found in the walls of blood vessels and the digestive organs.

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