Question 32

Phospholipids make up the bilayer of the cellular membrane.

The cellular membrane is primarily composed of phospholipids, which form a bilayer that serves as a barrier and structural foundation for the cell.

A) Nucleic acids

Nucleic acids, such as DNA and RNA, are not components of the cellular membrane bilayer. Instead, they are primarily involved in genetic information storage and transfer within the cell.

B) Phospholipids

Phospholipids are the key structural components of the cellular membrane bilayer. Their unique amphipathic nature allows them to arrange themselves into a double-layered structure that is essential for the membrane's integrity and functionality.

C) Proteins

While proteins are important components of the cellular membrane and are embedded within or attached to the phospholipid bilayer, they do not form the bilayer itself. Instead, they play various roles such as transport, signaling, and structural support.

D) Carbohydrates

Carbohydrates are not part of the membrane bilayer. They are typically attached to proteins and lipids on the extracellular side of the membrane, serving as recognition sites and contributing to cell-cell interactions.

Conclusion

Phospholipids are the fundamental building blocks of the cellular membrane bilayer, making option B the correct choice. Other options, while relevant to cellular structure and function, do not constitute the bilayer itself, highlighting the unique role of phospholipids in membrane architecture.