Table: Distinguishing Features of Bryophytes and Pteridophytes
The broad kingdom of Plantae consists of over 2 million different species. These organisms are all non-motile, eukaryotic, multi-cellular, and autotrophic. Their cells contain chlorophyll that helps in photosynthesis. They have various cell organelles for photosynthesis, reproduction, and support.
Classification of Plant Kingdom
All of the million species under Kingdom Plantae are classified into five subgroups based on their features, such as their plant body's complexity, presence or absence of a vascular system, and how they bear seeds. These five subgroups are thallophytes, gymnosperms, angiosperms, bryophytes, and pteridophytes.
Thallophyta:
They are primitive in terms of body structure and are called 'thallus,' meaning body structure is not well differentiated. They are mostly aquatic (marine or freshwater) or are found in moist habitats. A few examples of Thallophytes are Green algae like Volvox, Spirogyra, and brown algae like Fucus,
Bryophyta:
They are a little more complex in terms of body structure when compared with Thallophytes since they have root-like, stem-like and leaf-like structures. They are also terrestrial plants dependent on water for reproduction. It explains why they are called "Amphibians of the Plant kingdom" and why they are mostly seen in moist, shady places. Examples of Bryophytes include Marchantia, Funaria, and Sphagnum.
Pteridophyta:
The plants in this subgroup develop distinctly into the root, stems, and leaves. They are terrestrial and have a vascular system within the body, which helps conduct water and minerals to different body structures. They reproduce by dispersing spores and do not produce seeds. Selaginella and Pteris are some common examples.
Gymnosperms:
These are further developed plants that are capable of bearing naked seeds. They are fully terrestrial with differentiated body structures. They also have a developed vascular system to supply water and minerals to all these body structures. Pinus, Cycas, and Ephedra are Gymnosperms plants.
Angiosperms:
They are the most advanced plants with well-differentiated plant bodies, developed vascular systems, and bear seeds covered within fruits. The significant difference between bryophytes pteridophytes gymnosperms and angiosperms is the seed-bearing capacity. These include plants like Eucalyptus, rose, mango, etc.
Differentiation Between Bryophytes and Pteridophytes
There are several similarities between bryophytes and pteridophytes. The alternation of generation in bryophytes and pteridophytes are similar in both. To sum up, the significant difference between Bryophyta and Pteridophyta subgroups is tabulated below.
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Bryophyte Life Cycle
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Pteridophyte Life cycle
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Fun Facts
Researchers at the University of Exeter discovered that bryophytes might have caused an ice age during the Late Ordovician Mass Extinction. As they spread across the land, they altered the bedrock composition, sucked in all the air's carbon dioxide, and brought the temperature down.
Bryophytes can absorb water from the air and pass it on to leaves. Since they do not have a vascular system, they do not extract water from the soil through roots like other plants.
Fern species (Pteridophytes) can come in all sizes ranging from 3 inches to even 30 feet tall.
Ferns take up nitrogen from the air, and hence farmers sometimes use ferns as natural fertilizers in rice fields.
In ancient cultures, mosses were used to cleanse and heal wounds. When allied surgeons ran out of cotton on battlefields during World War I, they began to use moss as a temporary stopgap on wounds.
FAQs on Difference Between Bryophytes and Pteridophytes
1. What is the main difference between Bryophytes and Pteridophytes?
The primary difference lies in their vascular system. Bryophytes are non-vascular plants, meaning they lack specialised tissues like xylem and phloem for transporting water and nutrients. In contrast, Pteridophytes are vascular plants, which possess a well-developed transport system. This fundamental difference allows Pteridophytes to grow much larger and colonise a wider range of habitats compared to Bryophytes.
2. How does the dominant phase of the life cycle differ between Bryophytes and Pteridophytes?
The difference in the dominant life cycle phase is a key distinction.
- In Bryophytes, the main plant body is the gametophyte (haploid). The sporophyte (diploid) is smaller and nutritionally dependent on the gametophyte.
- In Pteridophytes, the main plant body is the sporophyte (diploid), which is independent and differentiated into true roots, stem, and leaves. The gametophyte is a small, independent but short-lived structure called the prothallus.
3. Why are Bryophytes often called the 'amphibians of the plant kingdom'?
Bryophytes are called the 'amphibians of the plant kingdom' because although they live on land, they are fundamentally dependent on water to complete their life cycle. Their male gametes (antherozoids) are motile and require a film of water to swim to the female gamete (egg) for fertilisation. This reliance on water for reproduction restricts them to moist and shady environments, similar to how amphibians require water for breeding.
4. What are the key similarities between Bryophytes and Pteridophytes?
Despite their differences, Bryophytes and Pteridophytes share several characteristics:
- Both groups exhibit a true alternation of generations.
- They reproduce via spores and do not produce flowers, fruits, or seeds.
- Both require water for sexual reproduction, as they have motile male gametes.
- The female reproductive organ in both groups is the archegonium.
5. How did the evolution of vascular tissue in Pteridophytes give them an advantage over Bryophytes?
The evolution of vascular tissues (xylem and phloem) in Pteridophytes was a major evolutionary advantage. This system allowed for the efficient transport of water and nutrients throughout the plant, enabling them to grow taller and compete for sunlight. It also provided rigid structural support and allowed for the development of true roots, stems, and leaves, making Pteridophytes the first truly successful terrestrial plants.
6. What is the ecological importance of Bryophytes?
Bryophytes play a crucial ecological role. They act as pioneer species, colonising bare rock and initiating the process of soil formation for other plants to grow. They also form dense mats on the ground that help in preventing soil erosion and retaining water, thus helping maintain moisture in the ecosystem. Species like Sphagnum moss form peat, which is a valuable resource.
7. Can you provide some common examples of Bryophytes and Pteridophytes?
Certainly. Common examples help illustrate the diversity within each group:
- Bryophytes: This group includes mosses like Funaria and Sphagnum, and liverworts like Marchantia and Riccia.
- Pteridophytes: This group includes ferns like Dryopteris and Adiantum (Maidenhair fern), horsetails like Equisetum, and club mosses like Selaginella.
8. Is the plant body differentiated in Bryophytes and Pteridophytes?
The level of differentiation is a key difference. The plant body of a Bryophyte is a thallus, which is not differentiated into true roots, stem, and leaves; it has root-like structures called rhizoids for anchorage. In contrast, the plant body of a Pteridophyte is well-differentiated into a true root, stem, and leaves, which is possible due to the presence of a vascular system.
