Which one of the following is a feature of Membrane ?

Which one of the following is a feature of Membrane ?

Bilayer of phospholipid molecule in which proteins and cholesterol are embedded
Bilayer of proteins molecule in which lipid and cholesterol are embedded
Bilayer of neutral lipid in which proteins and cholesterol are embedded
Bilayer of neutral lipid lacking cholesterol and proteins
This question was previously asked in
UPSC CDS-2 – 2022
A key feature of a biological membrane (like the plasma membrane) is that it is a bilayer of phospholipid molecules in which proteins and cholesterol are embedded.
– The fluid mosaic model describes the structure of the cell membrane.
– It consists of a double layer (bilayer) of phospholipid molecules, with their hydrophilic heads facing outwards and inwards, and hydrophobic tails facing each other in the interior.
– Various proteins are embedded within, associated with, or spanning this lipid bilayer, performing functions like transport, signaling, and enzymatic activity.
– Cholesterol molecules are also interspersed within the phospholipid bilayer in animal cells, helping to regulate membrane fluidity.
– Option B is incorrect because the fundamental structure is a lipid bilayer, not a protein bilayer.
– Options C and D are incorrect because biological membranes are primarily composed of phospholipids (amphipathic lipids), not neutral lipids, and typically contain proteins and often cholesterol (in animal cells).