Platyhelminthes, or flatworms, lack a true body cavity, making them aceolomates. Their bodies are filled with mesodermal cells, leaving no space for organs to be suspended in a coelom. This characteristic is a key feature distinguishing them from coelomates and pseudocoelomates.
| List I (Enzyme) | List II (Function) |
|---|---|
| (A) Cytochrome oxidase | (I) Electron transport system |
| (B) Topoisomerases | (II) Change linking number |
| (C) Cohesins | (III) DNA Replication |
| (D) PCNA | (IV) Cell cycle |