1. Tap vs Fibrous vs Adventitious Roots
| Feature | Tap root | Fibrous root | Adventitious root |
|---|---|---|---|
| Origin | Direct elongation of radicle forms primary root with lateral branches | Primary root short-lived; many roots arise from base of stem | Arises from plant parts other than radicle |
| Typical group | Dicotyledonous plants | Monocotyledonous plants | Various plants |
| Examples | Mustard | Wheat | Grass, Monstera, banyan |
| Major functions | Absorption, anchorage, food storage and synthesis of plant growth regulators | ||
2. Leaf Characters Compared
| Feature | Type 1 | Type 2 | Examples |
|---|---|---|---|
| Venation | Reticulate: veinlets form a network | Parallel: veins run parallel | Usually dicots / most monocots |
| Leaf | Simple: incision does not touch midrib or petiole | Compound: incision reaches midrib/petiole, forming leaflets | China rose / neem or silk cotton |
| Compound leaf | Pinnately: leaflets on common rachis | Palmately: leaflets at one point on petiole | Neem / silk cotton |
| Phyllotaxy | Alternate: one leaf per node | Opposite: pair per node; Whorled: more than two | Mustard / guava / Alstonia |
3. Racemose vs Cymose Inflorescence
| Feature | Racemose | Cymose |
|---|---|---|
| Main axis | Continues to grow | Terminates in a flower |
| Order of flowers | Acropetal: younger flowers towards apex | Basipetal: younger flowers towards base |
| Opening sequence | Centripetal in condensed inflorescences | Centrifugal |
| Key recognition | Indeterminate axis | Determinate axis |
4. Flower Symmetry, Sexuality and Ovary Position
| Character | Types | Examples / key point |
|---|---|---|
| Symmetry | Actinomorphic: any radial plane; zygomorphic: one vertical plane; asymmetric: none | Mustard / pea / canna |
| Sexuality | Bisexual: androecium + gynoecium; unisexual: one only | Flower reproductive organs |
| Hypogynous | Other whorls below gynoecium; ovary superior | Mustard, china rose, brinjal |
| Perigynous | Whorls on rim of thalamus at almost same level; ovary half-inferior | Plum, rose, peach |
| Epigynous | Thalamus encloses and fuses with ovary; other parts above; ovary inferior | Guava, cucumber, sunflower ray florets |
5. Floral Terms: Aestivation, Stamens and Carpels
| Feature | Type | Examples / meaning |
|---|---|---|
| Aestivation | Valvate / twisted / imbricate / vexillary | Calotropis / china rose / Cassia / pea |
| Stamen adhesion | Epipetalous / epiphyllous | Attached to petals in brinjal / perianth in lily |
| Stamen cohesion | Polyandrous / monadelphous / diadelphous / polyadelphous | Free / one bundle / two bundles / many bundles |
| Carpels | Apocarpous / syncarpous | Free in lotus and rose / fused in mustard and tomato |
| Placentation | Marginal / axile / parietal / basal / free central | Pea / tomato / mustard / sunflower / Dianthus |
6. Dicot Seed vs Monocot Seed
| Feature | Dicotyledonous seed | Monocotyledonous seed |
|---|---|---|
| Cotyledons | Two, often fleshy and food-storing | One large shield-shaped cotyledon: scutellum |
| Food reserve | May be endospermic (castor) or non-endospermic (bean, gram, pea) | Generally endospermic; endosperm bulky |
| Seed coat | Testa outside, tegmen inside; hilum and micropyle visible | Usually membranous and fused with fruit wall in cereals |
| Embryo protection | Radicle and plumule on embryonal axis | Coleorhiza covers radicle; coleoptile covers plumule |
| Example | Bean / gram / pea | Maize |