Question

Soap bubbles form because fatty acid salts organize into: (A) lysosomes. (B) micelles. (C) phospholipid bilayers. (D) hydrogen bonds.

Short answer

(B) micelles

Step-by-step solution

Understand the components

Identify the key term in the question: 'fatty acid salts.' These are compounds that have both hydrophobic (water-repelling) and hydrophilic (water-attracting) parts.

Recognize the behavior of fatty acid salts in water

In water, the hydrophobic tails of fatty acid salts avoid water and interact with each other, while the hydrophilic heads interact with the water.

Identify the structure formed

When fatty acid salts are in an aqueous solution, they tend to form spherical structures where the hydrophobic tails are hidden inside and hydrophilic heads face outward towards the water. This structure is known as a micelle.

Evaluate the answer choices

Consider each option: (A) lysosomes are cell organelles, not related to fatty acid salts; (B) micelles accurately describe the structure formed; (C) phospholipid bilayers are part of membrane structure, not spherical; (D) hydrogen bonds are types of chemical bonds, not structures.

Select the correct answer

Based on the analysis, the correct answer is (B) micelles.

Key concepts

micelles

In aqueous solutions, fatty acid salts naturally organize into structures called micelles. These spherical formations occur because fatty acid salts have dual characteristics—hydrophobic tails that repel water and hydrophilic heads that attract water. When introduced to water, the hydrophobic tails of these molecules try to avoid interacting with water and thus, gather in the center of the micelle. The hydrophilic heads, on the other hand, face outward, engaging with the surrounding water molecules. This arrangement minimizes the unfavorable interaction between water and the hydrophobic tails, creating a stable structure.

hydrophobic and hydrophilic interactions

Hydrophobic and hydrophilic interactions play crucial roles in the behavior of molecules in biological chemistry. Hydrophobic molecules, like the tails of fatty acids, do not mix well with water. They tend to clump together to minimize their exposure to water. Conversely, hydrophilic molecules, such as the heads of fatty acids, are attracted to water and interact favorably with it. These interactions are fundamental in the formation of structures like micelles:

• Hydrophobic tails stay inside the micelle, away from water.
• Hydrophilic heads face the water, making the structure stable.

This dynamic is essential for understanding why soap bubbles and other similar structures form.

aqueous solutions

Aqueous solutions are simply solutions where water is the solvent. Many chemical reactions and interactions in biological systems occur in aqueous solutions. When substances like fatty acid salts are placed in water, their hydrophilic and hydrophobic parts behave differently:

• Hydrophilic parts dissolve well and interact with water molecules.
• Hydrophobic parts do not dissolve, leading to the formation of structured arrangements like micelles.

Understanding these behaviors is crucial for studying various biological and chemical processes, as water is the most common solvent in biological systems.

biological chemistry

Biological chemistry focuses on chemical processes within and relating to living organisms. It explains how molecules like fatty acid salts behave in environments such as the human body, largely composed of water. Knowing how hydrophobic and hydrophilic interactions work helps in understanding cellular processes and the formation of structures like membranes and micelles. For instance:

• Fatty acids form the basic components of cell membranes.
• Hydrophilic heads face the watery cell exterior and interior, while hydrophobic tails remain inside.

This knowledge is fundamental in fields like biochemistry and molecular biology.