Final answer:
Most organelles in eukaryotic cells are indeed surrounded by membranes similar to the plasma membrane's phospholipid bilayer, but these membranes can differ in protein and lipid composition to suit their specific functions.
Step-by-step explanation:
The question posed about whether most organelles are bound by a membrane that differs from the plasma membrane's lipid bilayer has a precise answer: false. Most organelles within eukaryotic cells, such as the mitochondria, endoplasmic reticulum, Golgi apparatus, and lysosomes, are also enveloped by membranes that are primarily composed of a phospholipid bilayer embedded with proteins, similar to the plasma membrane. However, these membranes can have differences in the types and arrangements of proteins and lipids they contain, which are tailored to the specific functions of each organelle.
For instance, the mitochondrial membrane contains proteins that are involved in cellular respiration and ATP production. Similarly, the endoplasmic reticulum has proteins for protein synthesis and lipid metabolism, whereas the Golgi apparatus contains proteins involved in modifying, sorting, and packaging proteins and lipids for transport. Although the basic structure of a phospholipid bilayer with embedded proteins is common to all these membranes, the composition and function of the proteins and lipids can vary significantly, supporting the organelle-specific roles in the cell.