Question

Identify the hydrophobic and hydrophilic region(s) of a phospholipid.

Short answer

Question: Identify the hydrophobic and hydrophilic regions of a phospholipid. Answer: The hydrophilic region of a phospholipid consists of the head group, which includes a glycerol molecule, a phosphate group, and a polar organic group. The hydrophobic region comprises the two fatty acid tails, which are long hydrocarbon chains that repel water due to their nonpolar nature.

Step-by-step solution

Understand the structure of a phospholipid

Phospholipids are the main component of cell membranes and are composed of a hydrophilic (water-loving) head group and two hydrophobic (water-fearing) fatty acid tails. The head group typically contains a phosphate group, while fatty acid tails are long hydrocarbon chains.

Identify the hydrophilic head group

The hydrophilic head group of a phospholipid mainly consists of a glycerol molecule, a phosphate group, and usually a polar organic group (like choline). The negatively-charged phosphate group and the additional polar group allow the phospholipid head to form hydrogen bonds with water molecules, making it water-soluble. Hence, the head group is considered the hydrophilic region of the phospholipid. Here's a simple illustration of a phospholipid: ``` O || - P - O - CH_2 - O - R || OCH_2 ``` In this illustration, the phosphate group is represented by P and is connected to a glycerol molecule backbone (CH_2 - O - CH_2). The "R" is the polar organic group.

Identify the hydrophobic fatty acid tails

The hydrophobic fatty acid tails of a phospholipid consist of long hydrocarbon chains, which are nonpolar and do not interact with water molecules. Due to this lack of interaction with water, the fatty acid tails are considered the hydrophobic region of the phospholipid. The tails are usually depicted as zigzag lines connected to the glycerol backbone, as shown in the illustration below: ``` O || - P - O - CH_2 - O - R || OCH_2 - CH_2 - CH_2 - CH_2 - CH_2 - CH_2 - CH_2 - CH_2 - CH_2 - ... ... CH_3 ``` In this illustration, the hydrocarbon chains are represented by CH_2, followed by CH_3 at the end, indicating the hydrophobic fatty acid tails.

Recap the hydrophobic and hydrophilic regions of a phospholipid

The phospholipid consists of a hydrophilic head group (glycerol, phosphate group, and polar organic group) and two hydrophobic fatty acid tails (long hydrocarbon chains). The hydrophilic head group interacts with water molecules through hydrogen bonding, while the hydrophobic fatty acid tails repel water due to their nonpolar nature.