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Question 540
Biochemistry → General
Classification
Question
SSBAQuestion Header
Following fusion of a primary lysosome with a phagosome, which change most directly permits effective degradation of the engulfed material?
Question Stem
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Options
A
Formation of mitochondrial cristae
B
Acidification with activation of lysosomal enzymes
C
Polymerisation of tubulin
D
Attachment of ribosomes to its membrane
E
Replication of centrioles
Explanation
A primary lysosome becomes functionally active after fusion with a phagosome or endosome to form a secondary lysosome. Its hydrolytic enzymes are activated in the acidic environment.
Option Validity
A) Cristae are structural components of mitochondria.
C) Tubulin polymerisation relates to microtubules rather than lysosomal digestion.
D) Ribosome attachment characterises rough endoplasmic reticulum, not lysosomal activation.
E) Centriole replication occurs in relation to mitosis and does not activate lysosomal enzymes.
Further Reading
Saxena - MRCOG-1 Basic Sciences - Biochemistry, printed p.126.