Stems
- This plant part lies above the soil surface emerging from the plumule of the embryo, exhibiting growth that is positively phototropic and negatively geotropic
- These structures possess internodes and nodes from which different plant structures develop such as leaves, branches, flower buds, bracts
- Functions –
- Fluid and nutrition transport
- Mechanical support
- Appropriate arrangement of leaves and branches
- Nutrients storage
- Infinite growth
- Production of new organs/tissues
- Stem consists of the following morphologically – nodes, apical and axillary buds, internodes
- They develop from apical meristematic tissue – vegetative cones
Roots
- One of the major vegetative organs of vascular plants that are linked to their substrates are roots, ideally underground
- Found below the soil surface, it emerges from the radical of the embryo
- Exhibit growth that is positively geotropic and negatively phototropic
- They are not differentiated into internodes and nodes
- Functions –
- Water absorption
- Nutrient storage
- Anchoring plants
- Infinite growth
- Vegetative propagation
- Roots can be any of these depending on their origin and development – main root, adventitious roots, lateral roots
Difference Between Stems and Roots
Listed below are some of the important differences between stems and stems
| Characteristics | Stems | Roots |
| What it means | Plant structures bearing shoots and buds with leaves | Part of the vascular plant that is underground typically |
| Primary function | Supply minerals, water and food to all plant parts | Anchor the plant, water and mineral absorption |
| Property of growing towards light – Phototropism | Positively phototropic | Negatively phototropic |
| Property of growing towards soil – Geotropism | Negatively geotropic | Positively geotropic |
| Morphological differences | Bears leaves, flowers and buds | Bears flowers and buds |
| Instead of shoot tip possess a terminal bud | Root cap at the root tip | |
| Can either be unicellular or multicellular, stem hairs – present throughout | Unicellular root hair – at the cluster, behind root cap | |
| At younger stages, typically green in colour | Typically white in younger stages, grows darker | |
| Possess nodes and internodes | Nodes and internodes – absent | |
Root hair –
|
Root hair –
|
|
| Stem branches are exogenous and emerge from axillary buds | Root branches are endogenous, can emerge from any region | |
| Anatomical differences | Epidermal cells cutinized | Epidermal cells are not cutinized |
| Function of epidermis – protection | Function of epidermis – to absorb nutrients and water | |
| Epidermis of young stem has stomata | Stomata absent | |
| Cortex – narrow
Cortex differentiated into – outer, middle and inner cortex |
Cortex – broad
Cortex undifferentiated |
|
| Hypodermis present in an unrecognizable pattern in the endodermis | Hypodermis absent.
Endodermis is distinctly prominent |
|
| Chlorenchyma – present (in outer cortical cells) | Chlorenchyma – absent | |
| Pericycle – multilayered. Important in secondary thickening | Pericycle – uninuclear. Important in secondary thickening | |
| Xylem – endarch | Xylem – exarch | |
| Xylem and phloem fibres – present | Xylem and phloem fibres – absent | |
| Vascular bundles – conjoint and collateral | Vascular tissues – radial | |
| Secondary vascular growth – Present by cambium by both intra and interfascicular | Secondary vascular growth – if present emerges from conjunctive parenchyma and pericycle |
Stems and roots constitute important plant structures forming the root system and shoot system. Explore details on other plant structures, along with their differences, types and much more at BYJU’S.
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