Which of the following statements about skeletal muscles is incorrect?

Haryana CHO - 2022

Applied Anatomy

Easy

Appeared in: Haryana CHO - 2022

Explanation

The statement that skeletal muscles are spindle-shaped is factually incorrect, making it the correct answer to the question.
Skeletal muscle fibers are characterized by their long, cylindrical shape and run parallel to each other.
In contrast, smooth muscle fibers are spindle-shaped (fusiform), which means they are wider in the middle and taper towards the ends.
This difference in shape is a key histological feature used to distinguish between muscle types.

Option A: This is a correct statement about skeletal muscle. The sarcomere is universally recognized as the basic functional and contractile unit of striated muscle.
Option B: This is a correct statement about skeletal muscle. A defining feature of skeletal muscle fibers is the presence of multiple nuclei located at the periphery of the cell.
Option D: This is a correct statement. The sarcoplasmic reticulum is a specialized form of the smooth endoplasmic reticulum, adapted for calcium ion storage and release in muscle cells.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Histological Characteristics of Skeletal Muscle as background academic context rather than a clinical decision trigger.
Understanding the distinct features of muscle types is crucial for diagnosing and managing various medical conditions. For example, rhabdomyolysis involves the rapid breakdown of skeletal muscle, while leiomyomas (fibroids) are benign tumors of smooth muscle.
The peripheral location of nuclei in skeletal muscle is an important histological marker. In certain muscular dystrophies, the nuclei may migrate towards the center of the fiber, indicating a pathological process.
What if? If the question had asked for an incorrect statement about smooth muscle, 'Nuclei are peripherally placed' or 'Presence of sarcomeres' would be incorrect statements, as smooth muscle has a single central nucleus and lacks sarcomeres.

How to Approach the Question

First, identify that the question asks for the 'incorrect' statement. This means three of the options will be true facts about skeletal muscle, and one will be false.
Read the stem carefully to identify the subject: 'skeletal muscles'.
Evaluate each option individually based on your knowledge of muscle histology.
Option A: Recall the basic unit of muscle contraction. Is it the sarcomere? Yes.
Option B: Recall the nuclear arrangement in skeletal muscle. Are they peripheral? Yes.
Option C: Recall the shape of skeletal muscle fibers. Are they spindle-shaped? No, they are cylindrical. This is likely the incorrect statement.

Concept Tested & Keywords

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