Stem Anatomy of Monocots and Dicots

Introduction

The simulation “Stem Anatomy of Monocots and Dicots” aims to investigate the stem anatomy of monocot and dicot plants. The study of the internal structure of plants is called anatomy. Different organs in a plant show differences in their internal structure. Within angiosperms, the monocots and dicots are also seen to be anatomically different in the internal morphology of the stem.

Procedure

Collect a few thin green branches of recent growth of sunflower and maize stems, each having the thickness of a toothpick.
Wet the surfaces of the razor blade.
Carefully move the blade horizontally over the surface of the material in quick succession in such a manner that a very thin and complete slice of the material is cut.
Transfer all these sections into a watch glass containing water.
Choose the thinnest possible and complete sections, and transfer them into a watch glass containing safranin. Allow these to remain there for about 2 minutes.
With the help of a brush, gently transfer the section into another watch glass containing water to remove the excess safranin stain. Keep the material for a few minutes and transfer it into a watch glass containing a few drops of dilute acid in water to remove the excess safranin stain.
Wash with water and transfer the section onto a clean slide containing 1 drop of glycerine.
Place a coverslip over it, avoiding air bubbles, and transfer it to the stage of the microscope to be observed.

Observation

Monocot stems have a single-layered epidermis with no epidermal hairs. Trichomes are absent, the hypodermis is sclerenchymatous, the vascular bundles are scattered, conjoint, collateral, and closed, the bundle sheath is made of sclerenchyma, and ground tissue is present.

The dicot stem has a single-layered epidermis with epidermal hairs. Trichomes are present, hypodermis is collenchymatous, vascular bundles are arranged in a ring, conjoint, collateral, and open, and bundle sheath and ground tissue are absent.

Pith is well developed in dicots and not well developed in monocots. Secondary growth is seen in dicot stems and absent in monocot stems.

FAQs on Stem Anatomy of Monocots and Dicots

Q1. What is anatomy?

Ans: The study of internal morphology or structure, i.e., the cells of various tissues in an organ of a living body, is called anatomy.

Q2. Differentiate between dicot and monocot plants?

Ans: Depending on the nature of the embryo in the seed of a plant, plants are classified as monocotyledonous or dicotyledonous. Two cotyledons imply a dicot plant, such as the sunflower. One cotyledon implies a monocot plant, such as maize.

Q3. What are the characteristics of the monocot stem?

Ans: Monocot stem has single layered epidermis with no epidermal hairs. Trichomes are absent, hypodermis is sclerenchymatous, vascular bundles are scattered, conjoint, collateral and closed, bundle sheath is made of sclerenchyma, ground tissue is present.

Q4. What are the characteristics of the dicot stem?

Ans: The dicot stem has a single-layered epidermis with epidermal hairs. Trichomes are present, hypodermis is collenchymatous, vascular bundles are arranged in a ring, conjoint, collateral, and open, and bundle sheath and ground tissue are absent.

Q5. Write about the two differences between monocot and dicot stems.

Ans: Pith is well developed in dicots and not properly developed in monocots. Secondary growth is seen in dicot stems and absent in monocot stems.