Bryophyta Overview
Bryophyta is a group of non-flowering plants or embryophytes (land plants) that have rhizoids rather than real roots, have little or no structured vascular tissue, and have two generations that alternate: gamete bearing forms and spore-bearing forms. Gametophytes generated haploid sperm and eggs, which fused to make diploid zygotes, which then developed into sporophytes. Sporophytes create haploid spores during meiosis, which develop into gametophytes.
Bryophytes are gametophyte dominant, which means that the more prominent, longer-lived plant is haploid or gametophytic. The diploid sporophytes arise rarely and are connected to and nutritionally reliant on the gametophyte. Bryophytes have unbranched sporophytes that generate a single sporangium (spore-producing capsule).
What is Bryophyte?
Bryophyta, the division of green plants, refers to embryophytes, which are terrestrial plants, particularly non-vascular ones. This division consists of-
- Mosses- Class Bryopsida
- Liverworts- Class Marchantiopsida
- Hornworts- Class Anthocerotopsida
A bryophyte's primary distinguishing trait is the absence of real vascular tissue. Some have specialized tissues that transport water, although they are not regarded as real vascular tissues due to a lack of lignin. Bryophytes are thought to have developed from charophytes and are thought to be the earliest real plants to have evolved.
Examples of Bryophyta
Some of the common examples are as follows-
- Liverworts including Marchantia,
- Riccia
- Pellia
- Porella
- Sphaerocarpos, and Calobryum.
- Funaria, Polytrichum, and Sphagnum are examples of mosses.
- Hornworts include Anthoceros, Notothylas, and Megaceros.
Terminology of Bryophyte
Braun proposed the word "Bryophyta" in 1864. G.M. Smith classified this category as being between algae and pteridophytes.
Classification of Bryophyta
Campbell, Smith, Takhtajan, and others classified Bryophyta into three groups: Hepaticae, Anthocerotae, and Musci. Rothmaler modified the class names in 1951. He called them Hepaticae Hepaticopsida, Anthocerotae Anthocerotopsida, and Musci Bryopsida. In 1956, the International Code of Botanical Nomenclature acknowledged the aforementioned classifications. However, Proskauer (1957) modified the term Anthoceropsida to Anthocerotopsida, allowing the Bryophyta to be categorized as follows-
- Hepaticopsida (Hepaticae) – Liverwort
- Anthocerotopsida (Anthocerotae)—Hornwort
- Bryopsida (Musci) – Moss
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Characteristics of Bryophytes
The following are some of the characteristics of Bryophyta-
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General Characteristics |
Sexual Characteristics |
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The first terrestrial plants were bryophytes. They are amphibious in nature since they require water to fertilize. |
In general, asexual reproduction occurs by fragmentation. |
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The body of the plant is both gametophytic and sporophytic. The gametophyte stage is dominant, while the sporophyte stage is brief. Their primary plant structure is gametophytic (haploid). Their gametophytic body is mostly thalloid, with no discernible root, stem, or leaves. |
Sexual reproduction is oogamous, which means that the male gamete is motile and tiny, whereas the female gamete is non-motile and large. |
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Bryophytes lack real vascular tissues (xylem and phloem) for water and nutrient support and transfer. |
Multicellular and jacketed sexual organs. |
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They lack leaves in favor of leaf-like scales that contain chloroplasts for photosynthesis. |
Gametes are haploid and generated by gametophytes. |
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True stems are absent in bryophytes. |
Sporophytes develop spores, and the plant body as a whole is diploid. |
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They lack actual roots, but they are held in place by root-like structures called rhizoids. |
Male antheridia and female archegonia are invariably multicellular structures enclosed by a sterile jacket layer. |
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Rhizoids are unicellular organisms. These rhizoids operate like roots in terms of fixation and absorption, but they are not regenerated as genuine roots. |
The embryophytes' most basic members are known as bryophytes. The zygote generated as a result of fertilization produces a multicellular embryo that develops clearly within either an archegonium or an embryo sac. The ventral wall grows in size as the embryo develops. The calyptra is the protective envelope. |
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Spaorogonium is a single diploid sporophytic structure generated from the embryo that is not differentiated into a stem, leaves, or roots. It is normally made up of a foot, a seta, and a capsule. In other situations, the seta or the foot is missing. |
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The sporogonium has no soil connection and is generally dependent on gametophytes for water and minerals. |
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A haploid spore is disseminated from the sporogonium. |
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The unicellular haploid spore germinates to form a protometal phase, which is often filamentous. Sometimes ovoid, globose, plate-like, or thalloid gametophytic plants generate adult kinds. |
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Bryophytes exhibit heteromorphic alternation within a generation because gametophytes and sporophytes differ in morphology and alternate with one another. |
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Human and Environmental Significance of Bryophyta
Sphagnum, the genus of peat moss, is an economically significant bryophyte. Sphagnum peat collecting, processing, and sale is a multimillion-dollar industry. Peat is used in horticulture, as an energy source (fuel), and, to a lesser extent, in organic product extraction, whiskey manufacture, and insulation.
Bryophytes have a vital role in the creation of soil on barren land, the maintenance of soil moisture, and the recycling of nutrients in forest growth. Determining the existence of certain bryophytes is indeed important in measuring the productivity and nutritional condition of forest types. Furthermore, several biological phenomena have been identified via the study of bryophytes, which have had a significant impact on the advancement of research in fields such as genetics and cytology.
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Distribution and Habitat of Bryophytes
The bryophytes have a global distribution and may be found almost everywhere plants can thrive, with the exception of the oceans. They are equally at home in the wet mountain forests of the tropics and subtropics as they are in the Arctic tundra. The vast majority of bryophytes are damp-loving, primarily terrestrial plants that prefer the shady ground, moist rocks, tree roots, or other moist areas. A couple of them are aquatic plants.
- Floating Aquatic: Riccia Fluitants, R. natans (Ricciocarpos natans).
- Tree trunks: Hypnum cupressiforme
- Old walls: Tortula muralis.
- In deserts: Tortula desertrum.
- Saprophytes: Buxbaumia aphylla, Cryptothallus mirabilis.
- Fossil Bryophyte: Naiadata.
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Common Features of Bryophtya
The following are some of the common features of Bryophyta-
- An amphibious zone is a bryophyte.
- Bryophyta grows on tree trunks, rocks, and in damp soil.
- Bryophytes are the only embryophytes with a dominant gametophyte (haploid) stage in their life cycle.
- They are a varied and ancient category of non-vascular plants.
- They are divided into three major taxonomic groups. Mosses, liverworts, and hornworts have all developed independently.
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Differentiate between 3 Groups of Bryophyte
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Particulars |
Hornworts |
Liverworts |
Mosses |
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Capsule form |
Elongated |
Simple |
Differentiated (operculum, peristome) |
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Columella |
Present |
Absent |
Present |
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Dehiscence |
Longitudinal |
Longitudinal or irregular |
Transverse |
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Dispersion of spores |
Pseudo-elaters |
Elaters |
Peristome teeth |
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Growth |
Continuous |
Defined |
Defined |
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Maturation of spores |
Graduate |
Simultaneous |
Simultaneous |
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Persistance |
Persistent |
Ephemeral |
Persistent |
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Seta |
Absent |
Present |
Present |
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Stomata |
Present |
Absent |
Present |
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Structure |
Large, with chlorophyll |
Small, without chlorophyll |
Large, with chlorophyll |
Uses of Bryophytes
The following are some of the uses of Bryophyta-
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Environmental Uses |
Commercial Uses |
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The properties of bryophytes make them beneficial to the environment. Depending on the specific plant texture, bryophytes have been shown to help improve soil water retention and air space. |
Peat is a fuel made from dried bryophytes, most often sphagnum. |
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Fuel Packaging Wound Dressing |
Soil Conditioning Bioindicators Moss gardens Pesticides |
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Bryophytes are used in pollution studies to indicate soil pollution (such as the presence of heavy metals), air pollution, and UV-B radiation. |
Bryophytes' antimicrobial capabilities and capacity to hold water make them suitable packaging materials for vegetables, flowers, and bulbs. |
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Other bryophytes produce chemicals that are antifeedants, protecting them from slugs. |
Sphagnum was also employed as a medical bandage in World War I due to its antibiotic characteristics. |
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When Phythium sphagnum is sprinkled on the soil of germinating seeds, it inhibits the growth of "damping off fungus," which would otherwise kill young seedlings. |
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Conclusion
Bryophytes are an informal classification comprising three types of non-vascular plants: mosses, liverworts, and hornworts. The absence of actual roots, stalks, and leaves are distinguishing traits of bryophytes. Furthermore, rhizoids serve as roots, ultimately binding the plants to the surface. Rhizoids, on the other hand, do not absorb nutrients like typical plant roots.
Mosses require a damp climate or proximity to a body of water in order to thrive and spread. However, certain moss species have been shown to persist in dry and semi-arid conditions, such as deserts. In such instances, they can completely dry out and reach a condition of suspended animation. They recover and continue to develop when they come into contact with water again.