Plant Kingdom – Definition, Classifications, and Characteristics
The plant kingdom is the plant that contains all the plants in the world. These are multicellular eukaryotes. Characteristically, they have a rigid structure around the cell membrane called the cell wall. Plants have green pigment, which is very important for photosynthesis. Therefore, they have an autotrophic pattern of nutrition. Here you get the Classification of Plant Kingdom Class 11 Notes
A plant state is a very large group; Therefore, the state is further classified into subgroups. The best way to learn about plants is to first identify how taxonomy occurs within the state plant. Once you know the simple things, it will become easy to know the details of each plant.
Biologist Whittaker gave us a group of five states, which classified all living things into five regions – protista, monera, fungi, blond, and Animalia. To learn more about plants, it is important to know more about the Kingdom Gora or about the Kingdom of the Plant.
You will be surprised at the different types of plants that make it. You can find minute plants like algae and very tall plants like Sequoia. Some plants are beautiful and attractive with elements called flowers, some have no content. In some plants, you will find a suitable root system, shoot system and leaves, whereas in simple plants, it is only a thalloid structure.
Also Read Classification of Living Organisms Class 11 Notes
CLASSIFICATION OF PLANT KINGDOM
Of the earlier five kingdom classifications of the Whitaker (1969), the most widely accepted and most widely accepted traditional classification method was proposed by Eichler in 1883.
According to Eichler, the plant kingdom is divided into two sub-kingdom.
(i) Cryptogamae (plants without flowers and seeds) and
(ii) Phanerogamae (plants with flowers and seeds).
in Classification of Plant Kingdom Cryptogams are divided into subdivisions as described below, and they are further subdivided into Thalophyta, Bryophyta, and Pteridophyta. Panerocoms are divided into a sperm division, which will be further subdivided into subgroups. Gymnosperms and Angiosperms. Angiosperms are divided into two categories such as monocots and dicots.
Also Read Difference Between Living And Nonliving Organisms Biology Notes
ALGAE
Algae are simple, thalloid, chlorophyll-bearing (green), autotrophic, and primarily aquatic (both freshwater and marine) plants. They grow in different habitats such as Wet, rock, mud, and wet wood.
Some of them are also associated with fungi (lichen) and animals such as lsloth bear).
The size and shape of algae vary greatly. They range in size from unicellular microscopic patterns such as Chlamydomonas to Volvox colony-forming patterns and fibrous patterns such as Ulotrix and Spirogra.
The cells that make up the cell body are haploid and eukaryotic. Therefore, the body of the plant is a gametophyte. Mainly starch is a food reserve. Algae do not contain any vascular and mechanical tissue.
Algae breed according to vegetative, unusual, and sexual patterns. Breeding of plants takes place in pieces, with each piece developing into a new thallus. Homosexuals are produced by various types of spores, commonly known as zoospores. (Classification of Plant Kingdom)
They are flaky, lively, and give a fresh platter in germination. Sometimes under adverse conditions, mottled spores such as alpanosporse or hypnospores may form and eventually, a new thallus can form when environmental conditions are natural.
Sexual reproduction occurs through the fusion of two (male and female) gamets. gamets may be of the same size and maybe marked as Chlamydomonas or not marked as Spirogyra. Such reproduction by mixing similar comets is called isocomus.
In some species of Chlamydomonas, the two flagged gamets do not differ in size, and this reproduction is called anisogamous. As in Volvaux and Focus, the fusion between a large, immobile (stable) female gamete and a small motile male gamete is called oogamous.
The embryo stage is not in the life cycle of algae. Algae are divided into three main categories-
Chlorophyceae-Green Algae, Phaeophyceae–Brown Algae and Rhodophyceae-Red Algae
BRYOPHYTA
The name Bryophyta is derived from two Greek words, Bryon, meaning moss and phyton meaning plant. Bryophytes of about 25000 species are not vascular, they are the first plants in the soil and they usually grow in moist, and shaded areas.
They grow together and often make green carpet or mats on wet soil, rocks, walls, roofs, trunks, and hills during the rainy season. Bryophytes are also called amphibians plant state springs because they can live on land, but rely on water for sexual reproduction.
They play an important role in successful vegetation formation in bare rocks and dry soils. They contribute to soil formation and a portion of xerosere.
The Bryophytes are divided into 3 classes; Hepaticae (The Liverworts), Anthocerotae (Hornworts) and Musci (Mosses). Common representatives of Bryophytes are Riccia,
Bryophytes are divided into 3 categories such as Hepaticae-The Liverworts, Anthocerota-Hornworts and Musci-Moses. Common representatives of bryophytes are Riccia, Marchantia, Funaria, Porella, Sphagnum, Anthoceros, Polytrichum.
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Characteristics of Bryophytes
The defining feature of bryophytes, as previously mentioned, is that they are non-vascular plants. Other important properties of bryophytes include:
- Plants in this category have no roots, but stout and raw leaves.
- These contain “rhizoids” instead of roots, which help them pass through the surface of the plant.
- These roots or rhizoids do not absorb nutrients like the roots of other common plants.
- Moses travels through the water from his leaves and produces new moss in new places.
- Water is very important for the growth and spread of mosses. They can remain completely dry. When in contact with water, they regenerate and continue to grow.
Pteridophyta
Pteridophyta (pteridophytes) is a division of the plant state including vascular cryptogams. These are plants without flowers that represent the heritage of 2 separate and distinct generations.
First non-sexual, seed-bearing, sporophyte generation.
It usually appears as a relatively large plant, with water and water-soluble solvents containing vascular tissue containing stems, usually leaves and roots. Spores are formed by sporangia that attach to particular axes of leaves (such as ferns) or cones (such as horsetails and club-mosses) or leave axils that do not have specialized stems (such as Psilotaceae and some clubmosses).
The second is a sexual, gametophyte generation in which plants are usually small and have no stems, leaves, or roots. These plants carry the organs of the male-antheridia and the female-Archegonia together or in separate plants.
When eggs are fertilized in Arcagonia by sperm from Artidia, a new generation of sporophyte may develop as a result of this embryo. Sex cells have a single chromosome (haploid state) that is assigned to each embryo by each generation of the gametophyte.
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Pteridophyta Characteristics
- Pteridophytes are considered the first plant to evolve on soil
- These are cryptogams, seedless and vascular:
- The body of the plant consists of real roots, stems and leaves
- Create Spores in Sporangia
- Sporangia occur in groups of sporophylls
- Genital are multicellular:
- They show the true continuity of generations
Sporophyte generation and gametophyte generation are found in pteridophytes. The diploid sporophyte is an important plant body.
Gymnosperms
The meaning of Gymnosperms is “naked seed”, are a separate group of seeds and paraphyletic plants. Not all members of paraphilic groups are descendants of a common ancestor. Their properties include bare seeds, individual female and male gametes, air pollination, and tracheids (it carry water and solutions to the vascular system).
Gymnosperm seeds are not in the ovary Instead, they are exposed to cones or modified leaves. Sporophylls are specialized leaves that makeup sporangia. The term strobilus (plural = strobilis) describes the tight arrangement of sporophylls around a central spine, as seen on the cone. Some seeds are covered with sporophyte tissue when they mature. The layer of sporophyte tissue that surrounds megasporangium is, eventually, the nucleus, called the integument.
Gymnosperms dominated the Mesozoic period. They are favorable for areas where there is a shortage of freshwater for a part of the year or in weak nitrogen soils. Therefore, they are still a well-known prominent phylum in the coniferous biome or taiga, where evergreen cones have a selective advantage over cold and dry climates.
Green cones have a consistent photosynthetic level during the cold months and are ready for use on sunny days before spring. One drawback is that cones are more susceptible to infection to deciduous trees because cones do not lose leaves at once. Therefore, they do not sting the parasites and do not resume new distribution of leaves in the spring.
The life cycle of gymnosperms involves the change of generations, with the dominant sporophyte, the female gametophyte living, and the gametophyte being fewer. All gymnosperms are different. Male and female reproductive organs may develop into cones or strobili. Male and female sporangia are born on the same plant and are described as monoecious or on separate plants. The life cycle of a conifer is our example of reproduction in gymnosperms.
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Characteristics of Gymnosperms
- The essential properties of gymnosperm are:
- They do not produce flowers.
- Seeds are not formed inside the fruit. They are naked.
- They are located in cold areas where snowfall occurs.
- They form needle-like leaves.
- They are perennials or woody, forming trees or shrubs.
- They are not different in uterus, style and stigma.
- In the absence of stigma , they pollinate directly from the air.
- Male gametophytes produce two comets, but only one of them is active.
- They form cones with reproductive structures.
- The seeds have an endosperm, which stores food for plant growth and development.
- These plants have vascular tissues that help carry nutrients and water.
- The xylem has no vessels and the phloem has no cells and sieve tubes.
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Angiosperms
Angiosperms are flowering plants with seeds in the ovary. The ovule produces seeds and fertilizes the ovary. The 2,50,000 known species of Angiosperms are exceptionally large plants.
These are the latest and largest plants to appear on the Earth’s surface about 130 million years ago.
Today they are the most prominent plant group, and they grow in all types of habitats.
They range in size from small, almost microscopic Wolfia to eucalyptus trees up to 100 feet [100 m] high. They can be annual, twenty-year-old or perennial herbs, shrubs, or trees.
The body of the plant is different from that of the stem, roots, and leaves. At this time plants produce flowers which produce fruits and seeds. Vascular tissue is organized as vascular bundles.
xylem has vessels and phloem contains cells in addition to other calculators. Element. Flower reproductive organs, two or one sub-worm, perianth or Calyx, and corolla and two essential loops, the androecium, and the gynoecium. The calyx, corolla, whorls, androecium, and gynoecium are composed of petals, stamens, sepals,and carpels respectively.
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Characteristics of Angiosperms
- Angiosperms have different characteristics. The main features of angiosperms are:
- All plants have flowers at some point in their lives. Flowers are the reproductive organs of plants that provide them with a way to exchange genetic information.
- Sporophyte differs in stems, roots, and leaves.
- The vascular system consists of true xylem vessels and blooming cells.
- Sporophytes are diploid.
- Pollen (microsporophyll) and carbs (megasporophyll) are arranged in a structure called a flower.
- Each microsporophyll has four microsporangia.
- There are ovules in the ovary at the base of megasporophyll.
- Angiosperms are hereditary, i.e. they produce two types of spores, microspores (pollen particles) and megaspores.
- Single megaspore function is maintained permanently within the nucleus.
- Pollen is transferred from pollen to stigma and propagated by pollination. They are responsible for transferring genetic information from one flower to another. Pollen is much smaller than gametophytes or reproductive cells present in non-flowering plants.
- The root system consists of the cortex, phloem, xylem, and epidermis and is very complex.
- In combination, the flowers are double and triple, forming a diploid zygote and a triploid endosperm.
- Angiosperms can live in many types of habitats, including marine habitats.
- The fertilization process in angiosperms is rapid. Seeds are also produced rapidly due to small parts of female reproduction.
- All angiosperms are polluted and are the reproductive structure of flowers. They produce pollinators with hereditary information.
- carpels form seeds that can turn into fruit.
- Endosperm formation is one of the greatest benefits of angiosperms. The endosperm is formed after fertilization and is a source of food for growing seeds and plants.
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