Unlike other gymnosperms, Gnetum possesses vessels in its xylem, a characteristic typically associated with angiosperms. Vessels enable efficient water transport and represent an advanced evolutionary trait. This makes Gnetum an exceptional case among gymnosperms.
| 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 |