The key difference between coleoptile and coleorhiza is that the coleoptile is a protective sheath of the young shoot tip of monocot plants while the coleorhizae is a protective sheath of the radicle and the root of monocot plants.
Coleoptile and coleorhizae are two structures of monocot plants. In plant anatomy, the coleoptile and the coleorhiza play a protective function. These features present in the monocot seed. The characteristic features of both the structures differ with each other. Coleoptile is a green coloured protective sheath, which covers the plumule in monocot plants. In contrast, the coleorhiza is the protective sheath covering the radicle and the root cap of a monocot seed.
CONTENTS
1. Overview and Key Difference
2. What is Coleoptile
3. What is Coleorhiza
4. Similarities Between Coleoptile and Coleorhiza
5. Side by Side Comparison – Coleoptile vs Coleorhiza in Tabular Form
6. Summary
What is Coleoptile?
Coleoptile is one of the structures found in monocot seed. It acts as a protective covering for the plumule. The plumule is the shoot tip of the plant. The coleoptile emerges above the soil surface. It is green in colour. The green colour of the coleoptile is due to the presence of chlorophyll. Therefore, the coleoptile has the ability to photosynthesize. It has two vascular bundles on either side. The cells in the coleoptile specially adapted to increase the speed of the growth of the shoot. Therefore, the cells in the coleoptile increase in size upon maturation.
Figure 01: Coleoptile
As it performs photosynthesis, coleoptiles have a good supply of water via the presence of two water vessels. Upon reaching the soil surface, the growth of the coleoptile stops. Then through the terminal pore in the coleoptile, the first leaf will emerge out.
What is Coleorhiza?
Coleorhiza is a protective sheath in the monocot seed that protects the root tip or the radicle. It is a solid structure in plant anatomy. The coleorhiza is pale in colour and does not contain any chlorophyll.
Figure 02: Coleorhiza
Moreover, this grows towards the soil and does not emerge out of the soil. Due to this factor, they do not perform photosynthesis as they do not receive adequate sunlight.
The coleorhiza protects the root tip in a monocot seed. Once the coleorhiza emerges out of the seed, growth of the coleorhiza limits. The root emergence begins with the coleorhiza.
What are the Similarities Between Coleoptile and Coleorhiza?
- Coleoptile and Coleorhiza are structures of the monocot seed.
- Both act as a protective sheath.
- Also, both undergo rapid growth in its early phase.
What is the Difference Between Coleoptile and Coleorhiza?
Coleoptile and coleorhizae are two important sheaths in monocot plant seeds. They can be seen during the seed germination. Coleoptile is the sheath that protects the emerging shoot while coleorhiza is the sheath which protects the emerging root. Therefore, this is the fundamental difference between coleoptile and coleorhiza. Also, because of this difference in their function, coleoptile grows upwards from the soil while coleorhiza grows towards the soil. Another difference between coleoptile and coleorhiza is that the coleoptiles can photosynthesize while coleorhizae cannot.
The below infographic presents more details on the difference between coleoptile and coleorhiza.
Summary – Coleoptile vs Coleorhiza
The coleoptile and the coleorhiza are protective sheaths found in the monocot seed. The key difference between coleoptile and coleorhiza is the part in which they cover. The coleoptile protects the shoot tip whereas the coleorhiza protects the root tip. Due to the above difference, the coleoptile grows above the soil surface upwards whereas the coleorhiza grows towards the soil.
Reference:
1.“Coleoptile.” NeuroImage, Academic Press. Available here
Image Courtesy:
1.”Figure 32 02 10″By CNX OpenStax , (CC BY 4.0) via Commons Wikimedia
2.”14780362644″ by 14780362644 (CC0) via Flickr