Final answer:
The three amphipathic lipids present in the cell membrane are phospholipids, sphingolipids, and cholesterol. These components are crucial for the membrane's structure, with phospholipids forming the bilayer, sphingolipids contributing to cell recognition, and cholesterol modulating membrane fluidity.
Step-by-step explanation:
Three amphipathic lipids that are present in the cell membrane are phospholipids, sphingolipids, and cholesterol. Phospholipids, as the principal component, are composed of a hydrophilic head and two hydrophobic tails, allowing them to form the characteristic lipid bilayer of cell membranes. Sphingolipids, which also contain an amino alcohol sphingosine, play roles in cell recognition and signaling. Cholesterol modulates the fluidity and stability of the membrane.
Amphipathic molecules like phospholipids have both hydrophilic (water-loving) and hydrophobic (water-fearing) regions. The hydrophilic head faces the aqueous environments inside and outside the cell, while the hydrophobic tails face each other, forming the interior of the membrane—which is impermeable to most water-soluble substances.