Classification of the Plant Kingdom

Plant Kingdom

Plantae is the kingdom that contains all plants. They are multicellular, eukaryotic, and autotrophic creatures. The plant cell wall is stiff. Chloroplasts and chlorophyll pigment are found in plants and are essential for photosynthesis.

Characteristics

The following are a few characteristics of the Kingdom Plantae:

1. Plants are fundamentally autotrophic creatures that contain chlorophyll and are non-motile.
2. They are eukaryotic multicellular creatures.
3. Their cells include a cell wall composed of cellulose, hemicellulose, and pectin.
4. They are referred to as producers since they are at the bottom of the ecological pyramid.
5. They are immobile, i.e., rooted in one location.
6. They reproduce sexually, vegetatively, and asexually.
7. They demonstrate generational alternation.

Classification Principles

Taxonomy is a classification system. Biologists have classed and classified the various species that inhabit the globe in order to understand their similarities and differences. However, all plants are classified into a single Kingdom Plantae, which is further subdivided into subgroups. Plants are classified according to a few simple criteria. These include the following:

1. Plant Body- The presence or lack of a distinct root, stem, and leaves.
2. Vascular System – The presence or absence of vascular tissues such as xylem and phloem for the transportation of water and other substances.
3. Seed Development- Whether flowers and seeds are present or not. The seeds are either exposed or enclosed within the fruit.

Each group of plants has distinct and distinctive characteristics that are specific to that group. While thallophytes are the most green plants, angiosperms have a more complicated assembly and a well-developed vascular and reproductive systems.

Plant Classification

Taking all of these characteristics into account, the plant world has been divided into distinct subgroups. They include the following:

1. Thallophyta
2. Bryophyta
3. Pteridophyta
4. Phanerogamae
5. Gymnosperms
6. Angiosperm

Thallophyta

These are the lowest plants in the plant kingdom, as they lack a distinct body design. This means that the plant’s body does not have distinct roots, stems, or leaves. They are frequently referred to as algae and are permanently aquatic. Spirogyra, Chara, and Ulothrix are all examples.

Bryophyta 

These are terrestrial plants of a small size. They differentiate themselves through their body design, which includes a stem, leaf-like structures, and root-like features. However, they lack specialised tissue for conducting water and other chemicals. They like moist and sandy settings and are frequently referred to as the plant kingdom’s amphibians. Riccia, Funaria, and Marchantia are all examples.

Pteridophyta

These are thought to be the earliest known vascular plants. Apart from possessing a particular tissue for conduction, the plant body is separated into roots, stems, and leaves. This tissue aids in the transport of water and other compounds throughout the plant.

These plants produce naked embryos referred to as spores. These plants’ reproductive organs are concealed. Marselia and ferns are two examples.

Phanerogamae

Phanerogams are flowering plants that produce seeds. With a stem, leaves, and roots, the plant body is clearly defined. Seeds are produced by well-differentiated reproductive tissues. Additionally, these plants possess a well-developed vascular system.

Phanerogams are further categorised into two subcategories based on whether the seeds produced are bare or contained. Gymnosperms and Angiosperms are the two types of plants.

Gymnosperms

Gymnosperms are seedless plants. Gymnosperm plants are estimated to number approximately 650 species. Typically, the plants are perennial, evergreen, and woody.

They possess a well-developed circulatory system but lack vessels. Generally, the reproductive organs have the shape of cones or strobilus. Due to the absence of fruit formation, the seeds are referred to as naked. Cycas, Pinus, and Deodar are a few examples.

Angiosperms

Angiosperms are flowering plants that produce seeds. Seeds germinate inside tissues that are changed to become the plant’s fruit. Additionally referred to as flowering plants, they are abundant in nature. These are typically terrestrial plants that are annual, biennial, or perennial in nature. With xylem and phloem, the vascular system is extremely developed. Additionally, angiosperms have the trait of twofold fertilisation. Examples are mustard and pea plants.

Angiosperms are further classified according to their cotyledons (seed leaves) into Monocotyledonous and Dicotyledonous plants. Monocots have seeds with a single seed leaf and complicated vascular bundles. Dicots, on the other hand, have two cotyledons. The vascular bundle is ring-shaped.

Conclusion

Classification of plants has aided in our understanding of the numerous types of plant species found on the planet, as well as their evolution. Monocots and dicots, as well as Angiosperms and gymnosperms, are used to classify plants. The kingdom Plantae is divided into numerous groups or classifications.