Same chapter3 marksDifficulty: Medium
State two functions each of the endoplasmic reticulum, the Golgi apparatus and the lysosome.
Cell: The Unit of Life
3 marksDifficulty: Medium
Describe the fluid mosaic model of the plasma membrane.
Original Khojo Papers practice question — not from a past board paper.
Answer
The membrane is a bilayer of phospholipids with their hydrophilic heads outwards and hydrophobic tails inwards, in which protein molecules are embedded, some on the surface and some spanning the bilayer. The lipids and many of the proteins move laterally, so the membrane is fluid, and the scattered proteins give it the appearance of a mosaic.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The model was proposed by Singer and Nicolson in 1972.
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