how is the outermost layer of cell in plant, adopted to perform its function effectively?
how is the outermost layer of cell in plant, adopted to perform its function effectively?
The outermost cell layer of plants is Epidermis . The epidermis is the protective outer layer of clonally related cells covering all plant organs. It is composed of a number of specialised cell types which differentiate from the basal epidermal cell in adaptively significant frequencies and patterns. The epidermis is unique in developing solely through anticlinal divisions, generating a sheet of cells overlying the rest of the plant. This sheet is connected physically and biochemically to the cell layers below, with information exchange occurring in both directions. The specialised cell types within the epidermis develop either through communication among themselves, or, in some cases, through communication also with the underlying cell layers. Brief descriptions of the molecular genetic control of trichomes, stomata, root hairs and petal conical‐papillate epidermal cells are provided here, along with a summary of the role of the cuticle in epidermal cell morphology and of the interplay between cuticle regulation and cell morphology.
Key Concepts - The plant epidermis is a single layer of clonally related cells.
- Plant epidermis fulfils a basic protective function, but specialised cells within the epidermis have specific roles.
- The seedling epidermis arises by isolation of the outer layer during embryogenesis. The aerial epidermis and the root epidermis originate later, in the shoot apical meristem and in the root apical meristem, respectively.
- Stomatal guard cells allow gas exchange, and their patterning is controlled by cell‐lineage‐based developmental mechanisms.
- Trichomes protect the plant from herbivores, and their patterning is controlled by cell–cell interactions.
- Root hairs increase surface area for water and nutrient uptake, and are patterned according to positional signals.
- The cuticle overlying the epidermis can contribute to epidermal cell shape and function.
- There is interplay between the regulation of epidermal cell shape and the regulation of cuticle production.
Keywords: trichomes; stomata; differentiation; development; patterning; root hairs; cuticle
The epidermis is the protective outer layer of clonally related cells covering all plant organs. It is composed of a number of specialised cell types which differentiate from the basal epidermal cell in adaptively significant frequencies and patterns. The epidermis is unique in developing solely through anticlinal divisions, generating a sheet of cells overlying the rest of the plant. This sheet is connected physically and biochemically to the cell layers below, with information exchange occurring in both directions. The specialised cell types within the epidermis develop either through communication among themselves, or, in some cases, through communication also with the underlying cell layers. Brief descriptions of the molecular genetic control of trichomes, stomata, root hairs and petal conical‐papillate epidermal cells are provided here, along with a summary of the role of the cuticle in epidermal cell morphology and of the interplay between cuticle regulation and cell morphology.
Key Concepts- The plant epidermis is a single layer of clonally related cells.
- Plant epidermis fulfils a basic protective function, but specialised cells within the epidermis have specific roles.
- The seedling epidermis arises by isolation of the outer layer during embryogenesis. The aerial epidermis and the root epidermis originate later, in the shoot apical meristem and in the root apical meristem, respectively.
- Stomatal guard cells allow gas exchange, and their patterning is controlled by cell‐lineage‐based developmental mechanisms.
- Trichomes protect the plant from herbivores, and their patterning is controlled by cell–cell interactions.
- Root hairs increase surface area for water and nutrient uptake, and are patterned according to positional signals.
- The cuticle overlying the epidermis can contribute to epidermal cell shape and function.
- There is interplay between the regulation of epidermal cell shape and the regulation of cuticle production.
Keywords: trichomes; stomata; differentiation; development; patterning; root hairs; cuticle
