How do the phospholipids in archaea differ from those in other cells?a. They have tails made of unsaturated fatty acids instead of saturated fatty acids.b. They do not contain hydrocarbon chains.c. They have isoprenoid tails instead of fatty acid tails.d. They have two hydrocarbon chains instead of three hydrocarbon chains.

Verified step by step guidance

1. Step 1: Understand the structure of phospholipids. Phospholipids are a type of lipid molecule that is the main component of the cell membrane. They are composed of two fatty acid tails and a phosphate group head.
2. Step 2: Recognize that the structure of phospholipids can vary between different types of cells. In particular, the structure of phospholipids in archaea, a type of single-celled microorganism, differs from those in other cells.
3. Step 3: Evaluate each of the given options. Option a suggests that archaeal phospholipids have tails made of unsaturated fatty acids instead of saturated fatty acids. Option b suggests that they do not contain hydrocarbon chains. Option c suggests that they have isoprenoid tails instead of fatty acid tails. Option d suggests that they have two hydrocarbon chains instead of three.
4. Step 4: Recall that the key difference between archaeal phospholipids and those in other cells is in the nature of their tails. Archaeal phospholipids have isoprenoid tails, which are made up of repeating five-carbon units, instead of the fatty acid tails found in other cells.
5. Step 5: Based on this information, the correct answer is option c: They have isoprenoid tails instead of fatty acid tails.

Key Concepts

Phospholipid Structure

Phospholipids are molecules that form the fundamental structure of cell membranes, consisting of a hydrophilic (water-attracting) 'head' and hydrophobic (water-repelling) 'tails.' In archaea, the tails can differ significantly from those in bacteria and eukaryotes, influencing membrane fluidity and stability.

Isoprenoid Tails

In archaea, phospholipids often feature isoprenoid tails, which are branched hydrocarbons derived from isoprene units. This contrasts with the straight-chain fatty acids found in the phospholipids of bacteria and eukaryotes, providing archaea with unique membrane properties that enhance their survival in extreme environments.

Membrane Composition and Function

The composition of cell membranes, including the types of phospholipids present, is crucial for maintaining cellular integrity and function. In archaea, the unique structure of their phospholipids contributes to their ability to thrive in extreme conditions, such as high temperatures and salinity, by providing greater membrane stability.