Lenticular cells are parenchyma cells that form lenticels, which are pore-like structures found on plant surfaces.
Understanding Lenticels and Lenticular Cells
Lenticels are essentially small openings or pores on the surface of plant organs like stems, petioles (leaf stalks), and fruits. They are made up of a collection of loosely packed parenchyma cells, which are referred to as lenticular cells. These cells facilitate gas exchange between the plant's internal tissues and the surrounding atmosphere. Unlike stomata, which can open and close to control gas exchange, lenticels remain permanently open.
Key Characteristics of Lenticels:
- Location: Found on the epidermis of various plant organs such as stems, petioles, and fruits.
- Composition: Made up of parenchymatous cells, which are called lenticular cells.
- Function: Facilitate gas exchange (primarily oxygen and carbon dioxide) for respiration.
- Open State: Unlike stomata, they are always open.
- Visibility: Lenticels are often visible to the naked eye, especially on the surfaces of some fruits.
Examples of Lenticels:
| Plant Organ | Example |
|---|---|
| Fruit | Mango, apple, avocado |
| Stem | Bark of woody plants |
| Petiole | Stems and petioles of many dicotyledonous plants |
Why are Lenticular Cells Important?
Lenticular cells, by forming the structure of lenticels, are essential for plant respiration. Because stems and roots may have corky or waxy layers that hinder gas exchange, lenticels offer a pathway for these critical gas exchanges to take place.
Practical Insights:
- Visible lenticels can be an identifying feature for certain types of fruits.
- Lenticels are important in plant physiology for allowing the diffusion of gases in and out of plant tissues.
- Lenticels can sometimes be entry points for pathogens; however, their primary function remains crucial for plant survival.
In conclusion, lenticular cells are a specific type of parenchymatous cell that comprise the permanently open pores known as lenticels, which are crucial for gas exchange in plants.
