The nature of phospholipid head and tail are ________ and _________ respectively.
Polar hydrophobic and non-polar hydrophilic
Polar hydrophilic and non-polar hydrophobic
Polar hydrophilic
Non-polar hydrophobic
Phospholipids, which are organized in a bilayer, make up the majority of lipids. The heads (the portion of phosphorus) are polar, whereas the tails (the portion of lipids) are non-polar. The heads, which make up the exterior and inner linings, are "hydrophilic" (loving water), but the tails, which are exposed to the cell membrane's interior, are "hydrophobic" (water-fearing). Hence, option 2 is the correct answer.
Explanation for the incorrect options :
Option 1 is incorrect because the hydrophilic head is charged or polar, it dissolves in water. This enables it to create hydrogen bonds or electrostatic interactions with the water molecules. Yet, because the hydrophobic tail is non-polar and uncharged, it cannot interact with water molecules and is hence insoluble in water.
Option 3 is incorrect because the phospholipid tail is non-polar and hydrophobic in nature.
Option 4 is incorrect because the phospholipid head is polar and hydrophilic in nature.