The Most Tested NEET Trap: Stem vs. Root
| Feature | Potato (STEM) | Sweet Potato (ROOT) | Ginger (STEM) | Onion (STEM) | Colocasia (STEM) |
|---|---|---|---|---|---|
| Modification Type | Underground stem tuber | Tuberous adventitious root | Rhizome | Bulb | Corm |
| Nodes | Present (with eyes) | Absent | Present (clear) | Present (disc) | Present |
| Internodes | Present | Absent | Present | Absent (compressed) | Present |
| Axillary Buds | Present (the "eyes") | Absent | Present | Present | Present |
| Scale Leaves | Present | Absent | Present (cataphylls) | Present (fleshy layers) | Present (papery) |
| Turns Green in Light | YES | No | No (yellow turmeric) | No | No |
| Family | Solanaceae | Convolvulaceae | Zingiberaceae | Liliaceae | Araceae |
Mnemonic: "BINS confirm STEM" — Buds + Internodes + Nodes + Scale leaves = STEM
Subaerial Stem Modifications:
| Type | Example | Key Feature |
|---|---|---|
| Runner | Cynodon (doob grass) | Creeps on soil surface |
| Stolon | Fragaria (strawberry) | Arching branch, roots at tips |
| Offset | Eichhornia (water hyacinth) | Short horizontal branch in aquatic plants |
| Sucker | Chrysanthemum | Underground branch surfaces near parent |
Aerial Stem Modifications:
| Type | Example | Function |
|---|---|---|
| Tendril | Passiflora (passion flower) | Climbing support |
| Thorn | Bougainvillea | Protection (from axillary bud) |
| Phylloclade | Opuntia | Photosynthesis (leaf replaced by stem) |