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Question 557
Biochemistry → General
Classification
Question
SSBAQuestion Header
Which statement most accurately describes the composition of cytoplasm?
Question Stem
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Options
A
It consists predominantly of DNA and histones
B
It contains approximately 80% water within a complex protein-and-lipid biochemical structure
C
It consists predominantly of RNA and proteins in equal proportions
D
It is a lipid bilayer containing respiratory-chain proteins
E
It is composed mainly of tubulin and actin
Explanation
Cytoplasm is described as jelly-like material enclosed by the trilaminar cell membrane. It has a complex biochemical structure containing proteins and lipids and is nearly 80% water. Cytoplasmic organelles are contained within it.
Option Validity
A) DNA associated with histones forms chromatin within the nucleus.
C) Ribosomes are RNA-protein complexes, but this does not describe the overall composition of cytoplasm.
D) Respiratory-chain proteins are associated with mitochondrial cristae.
E) Tubulin and actin are components of the cytoskeleton rather than the predominant composition of cytoplasm.
Further Reading
Saxena R. Textbook for MRCOG-1: Basic Sciences in Obstetrics & Gynaecology. Chapter 4 — Structure and Function of Normal Cell. Printed page 124.