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Question 543
Biochemistry → General
Classification
Question
SSBAQuestion Header
Which structural relationship best explains continuity between the nuclear envelope and the endoplasmic reticulum?
Question Stem
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Options
A
The inner nuclear membrane forms the Golgi cis face
B
Nuclear pores are continuous with mitochondrial cristae
C
The nucleolus forms the endoplasmic-reticulum lumen
D
The outer nuclear membrane is continuous with endoplasmic reticulum and the intervening space communicates with its lumen
E
Chromatin extends directly into rough endoplasmic reticulum
Explanation
The nuclear membrane is double and porous. Its outer membrane is continuous with the endoplasmic reticulum, and the space between the nuclear membranes is continuous with the endoplasmic-reticulum lumen.
Option Validity
A) The Golgi cis face receives material from endoplasmic reticulum but is not formed by the inner nuclear membrane.
B) Mitochondrial cristae are unrelated to nuclear pores.
C) The nucleolus contains RNA and protein and does not form the endoplasmic-reticulum lumen.
E) Chromatin consists of DNA and histone and does not extend directly into rough endoplasmic reticulum.
Further Reading
Saxena - MRCOG-1 Basic Sciences - Biochemistry, printed p.127.