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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
The lipid bilayer of cell membrane exist as
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The correct answer is  The lipid bilayer shows free lateral movement of its components, hence the membrane is said to be fluid in nature. Fluidity enables the membrane to perform endocytosis and exocytosis. However, the components do not freely move from inner to outer layer or outer to inner layer (flip-flop movement is restricted). During apoptosis (programmed cell death), flip-flop movement occurs. Somewhat similar to a gel.Ref: DM Vasudevan, page no: 11