Asked by Tyler Novak on May 07, 2024
Verified
What produces the striations of a skeletal muscle cell?
A) the sarcoplasmic reticulum
B) t-tubules
C) sarcoplasm
D) myofilaments
Myofilaments
The filamentous components of muscles, comprising mainly of actin (thin filaments) and myosin (thick filaments), essential for muscle contraction.
Sarcoplasmic Reticulum
A specialized type of smooth endoplasmic reticulum found in muscle fibers, critical in regulating calcium ions and thus muscle contraction.
T-tubules
Tubular extensions of the cell membrane in muscle cells, transmitting electrical signals from the surface to the interior of the muscle fiber.
- Learn the essential architecture and action of muscle cells.
Verified Answer
CC
Christian CarturanMay 08, 2024
Final Answer :
D
Explanation :
The striations of a skeletal muscle cell are produced by the organized arrangement of myofilaments (thin and thick filaments) within the myofibrils. The repeating pattern of light and dark bands seen under a microscope is a result of the overlapping pattern of actin and myosin filaments within the sarcomere, the basic unit of contraction in a muscle cell. The sarcoplasmic reticulum and t-tubules are involved in regulating the release of calcium ions, which is necessary for muscle contraction, but they do not directly produce the striations. The sarcoplasm is the cytoplasm of a muscle cell and does not contribute to the striations.
Learning Objectives
- Learn the essential architecture and action of muscle cells.