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Question 523
Biochemistry → General
Classification
Question
SSBAQuestion Header
A muscle cell requires a cytoskeletal intermediate filament to maintain its structural integrity. Which protein is the most appropriate component?
Question Stem
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Options
A
Tubulin
B
Actin
C
Keratin
D
Desmin
E
Myosin
Explanation
Intermediate filaments are approximately 10 nm in diameter and contribute to cellular structural integrity. Their constituent proteins include keratin, glial filaments, neurofilaments, vimentin and desmin. Desmin is the relevant intermediate-filament protein in muscle.
Option Validity
A) Tubulin forms microtubules rather than intermediate filaments.
B) Actin is a principal component of microfilaments.
C) Keratin is an intermediate-filament protein but is not the appropriate muscle-associated component in this question.
E) Myosin is associated with microfilaments rather than intermediate filaments.
Further Reading
Richa Saxena. Textbook for MRCOG-1: Basic Sciences in Obstetrics & Gynaecology. Biochemistry and Nutrition — Biochemistry — Cytoskeleton. Printed page 128.