Plantae is the plant kingdom that encompasses all of the world’s plants. They are eukaryotes, which are multicellular organisms. They are distinguished by the presence of a stiff structure known as the cell wall that surrounds the cell membrane. Chlorophyll, a green-colored pigment found in plants, is essential for photosynthesis. As a result, they eat in an autotrophic manner.
Whittaker, a biologist, devised the Five Kingdom Grouping, which divides all living species into five kingdoms: Protista, Monera, Fungi, Plantae, and Animalia. To learn more about plants, it’s important to understand the Kingdom Plantae, or simply the plant kingdom.
The Level of Classification is Grounded on the Following Three Criteria
Plant Body: whether or not the body is made up of well-differentiated assemblies.
Vascular System: Whether or whether the plant has a vascular system for transporting chemicals.
Seed Development: whether or not the plant allows flowers and seeds; if so, whether or not the plant is surrounded by fruits.
Each plant group has distinct and distinctive characteristics that are specific to that group. While thallophytes are the greenest plants, angiosperms are plants with a complex assembly and a well-developed vascular and reproductive systems.
Classification of Plants
The plant kingdom has been divided into five subgroups based on these characteristics. The following are the details:
- Thallophyta
- Bryophyta
- Pteridophyta
- Gymnosperms
- Angiosperm
Thallophyta
The Thallophyta subcategory includes all plants with short, well-differentiated bodybuilding. Algae are commonly referred to as thallophytes. Their popularity stems from the fact that they are water-based. Spirogyra, Chara, Ulothrix, and others are some instances.
Division of Thallophyta:
Algae
They are thalloids that contain chlorophyll. They are primarily water plants that are autotrophic. Green algae methods have been observed to have a symbiotic interaction with sloths, which are native to the lush tropical jungles of South and Central America. Sloth fur is scratchy and absorbs water quickly. As a result, sloth fur treatments provide a moist, humid environment in which algae can thrive. In exchange, the algae provide the sloth with additional nutrition as well as provide cover from predators. Spirogyra is an example.
Fungi
They are achlorophyllous thallophytes, which means they do not produce chlorophyll. Fungi may form a symbiotic connection with algae or cyanobacterium to counter this disadvantage. Because the algae has chlorophyll, it can produce food, and the fungi provide a safe environment that protects the algae from ultraviolet rays. Lichen is an example of two organisms working together as a single unit.
Bryophyta
Bryophytes feature distinct plant characteristics such as leaf structures and stems. However, they lack a vascular system for transporting substances throughout the plant. Bryophytes are amphibians of the plant kingdom because they originate in both terrestrial and aquatic settings. This subcategory includes mosses and Marchantia.
A bryophyte’s primary distinguishing trait is that it lacks real vascular tissue. Although some tissues are used to transport water, they are not considered real vascular tissue due to a lack of lignin.
Pteridophyta
Pteridophytes feature distinct stem, root, and leaf structures, as well as vascular tissue. Pteridophytes include plants including ferns, horsetails, and Marsilea.
Pteridophytes are divided into two groups:
Lycopodiopsida
- Lycopodiidae (mosses)
- Selaginellidae (spike mosses, quillworts)
Polypodiopsida
- Psilotidae: Ophioglossales (example. grape ferns) and Psilotales.
- Equisetidae (horsetails)
- Polypodiidae (the most species-rich group, leptosporangiate ferns)
- Marattiidae (marattioid ferns)
Sporangia’s Advanced Spores Are Homosporous: The assembly of spores is known as sporangium. They are both homosporous (meaning they produce only one type of spore) and heterosporous (meaning they produce more than one type of spore) (meaning: two kinds of spores are formed.)
Sporangia are formed in sporophyll groups: Sporophylls are leaves that can survive sporangia.
Gymnosperms
Gymnosperms are plants with a distinct plant body, vascular structure, and seed production. Gymno means nude, and spermatic means seed, hence the name is derived from Greek words. Gymnosperm seeds are bare, meaning they are not enclosed within a fruit. This group includes the evergreen woody trees that are always present. Pines, deodar, redwood, and other woods are examples.
Angiosperms
Seed-bearing plants with distinct plant bodies are known as angiosperms. The name comes from the Greek terms angios, which means enclosed, and sperma, which means seed. Unlike gymnosperms, angiosperm seeds are enclosed within the fruits. Flowering plants are commonly referred to as angiosperms. It contains, for example, a mango tree and a pomegranate plant. Cotyledons are embryonic leaves that grow into seeds.
Angiosperms are classified into two groups based on the number of cotyledons found in their seeds:
Monocotyledons are a type of monocotyledon (monocots)
Dicotyledons are a type of dicotyledon (dicots.)
The normal vascular bundle containing xylem and phloem components for the conduction of water, minerals, and nutrients is found in all angiosperm plants. With a well-built root system, shoot system, and leaves, the plant body stands out. Flowers are present in the form of specific structures. Male and female gametes mature within these flowers. When these blooms mature after pollination, they produce fruits that contain the seeds.
Angiosperms can be found in a number of settings and in a wide range of sizes. The Australian mountain ash tree is around 100 metres tall, whereas Wolfie is a tiny angiosperm. The angiosperms have seen a lot of different things. Several vegetation, including large woody trees, shrubs, and even herbaceous plants, are present. These plants have multiple adaptations in their roots, stems, and leaves in response to the environment in which they grow.
Classification of Angiosperms
Angiosperms are classified into two groups based on the types of cotyledons they have. Monocotyledons and dicotyledons are the two types of plants. The seeds of dicotyledonous angiosperms have two cotyledons, while monocotyledonous angiosperms have just one.
Monocotyledonous Plants
Monocots have a variety of characteristics, including adventitious roots, simple leaves with identical venation, and trimerous blooms. The number of vascular bundles is greater and they are all closed. Bamboos, bananas, sugarcane plants, cereals, lilies, and other plants are among the examples.
Dicotyledonous Plants
Dicotyledonous plants have two (2) cotyledons that are connected by a taproot. The leaves have a reticulate venation pattern. Tetramerous and pentamerous flowers exist. Vascular bundles are typically grouped in a ring and range in number from 2 to 6. Grapes, sunflowers, tomatoes, dandelions, and potatoes are just a few examples.
Conclusion
Because the plant kingdom is such a large group, it is further divided into subgroups. The easiest approach to learn about plants is to understand how they are classified under the Kingdom Plantae. Once you’ve mastered the fundamentals, it’ll be much easier to learn more about each plant in depth.
Based on their ability to generate seeds, the plant world has been divided into two groups: cryptogams and phanerogams.
‘Phanerogams’ are plants with visible reproductive organs that can produce seeds. Gymnosperms and Angiosperms both belong to the phanerogams group.