Monocot and Dicot Root
9 Minutes
Monocot and dicot roots for students: learn how to identify root structures, cell layers, and vascular bundles in an English science lesson.
- Comparing monocot and dicot seeds using rice and groundnut
- The four cell layers of a plant root and their functions
- Vascular bundle layout, cambium, pith, and fibrous vs taproots
What this lesson teaches
Monocot and dicot roots are the two distinct root systems found in flowering plants, differing in how their inner transport tissues are organized and how their root branches grow. While the outer cell layers function similarly in both types, key structural differences inside the vascular bundle determine whether a plant is a monocotyledon or a dicotyledon.
Monocot and dicot seeds
Flowering plants are divided into monocotyledons and dicotyledons based on their structure, which is visible starting from the seed. A dicot seed, such as a groundnut, can be split evenly into two halves. A monocot seed, such as a grain of rice, cannot be split into two parts. Because their seeds are built differently, the plants that grow from them develop noticeable differences throughout their stems and roots.
The four cell layers of a root
- The epidermis is the outer protective layer whose root hairs absorb surrounding water from the soil.
- The cortex receives this absorbed water from the root hairs and transfers it inward to the endodermis.
- The endodermis has barrel-shaped cells hardened by a polymer called suberin, creating Casparian strips that pass water inward.
- The vascular bundle contains xylem to supply water throughout the plant and phloem to distribute food.
Differences in the vascular bundle
- In a dicot root, the vascular bundle is arranged in the shape of a plus sign, whereas in a monocot root, it is arranged in a circular ring.
- A dicot root contains a specialized tissue layer called cambium located between the xylem and phloem, which is absent in a monocot root.
- A monocot root contains a central space called the pith that is used to store food, while a dicot root lacks a pith completely.
Taproots versus fibrous roots
A plant root can also be identified without a microscope simply by looking at its outward shape. Dicot plants develop a primary taproot with secondary lateral roots branching out because they contain cambium tissue. Monocot plants lack cambium, which prevents secondary roots from forming. Instead, monocots produce a fibrous root system that looks like coconut coir.