Question

Explain how hydrophilic and hydrophobic properties of phospholipids help to maintain the structure of the cell membrane.

A) By forming a fluid mosaic, aiding in cell recognition, regulating cell transport
B) By repelling water molecules, providing a barrier, allowing selective permeability
C) By binding proteins, facilitating cellular communication, preventing fluidity
D) By restricting movement, enabling active transport, facilitating diffusion

Answer 1

The hydrophilic heads and hydrophobic tails of phospholipids form a bilayer that creates a selectively permeable cell membrane, essential for maintaining internal homeostasis by controlling substance passage.

Step-by-step explanation:

The hydrophilic and hydrophobic properties of phospholipids play a critical role in maintaining the structure of the cell membrane. The hydrophilic 'heads' of phospholipids are attracted to water, while the hydrophobic 'tails' repel water. This causes phospholipids to arrange themselves into a bilayer with the hydrophobic tails facing inward, away from the water, and the hydrophilic heads facing outward, towards the water. This arrangement forms a selectively permeable barrier that enables the cell to maintain its internal environment by controlling the passage of substances into and out of the cell.

Moreover, the membrane's lipid bilayer structure provides selective permeability, which is essential for passive transport. Phospholipids are tightly packed, with a hydrophobic interior that allows only small, nonpolar materials to move through the lipid bilayer without assistance, while water-soluble materials require help to cross. This property is crucial for maintaining homeostasis within the cell.