Plant Kingdom Brief Summary
Classification Systems
Artificial System: Based on gross superficial morphological characters such as habit, color, number, and shape of leaves.
Natural System: Based on natural affinities among organisms, including internal features like ultrastructure, anatomy, embryology, and phytochemistry.
Phylogenetic System: Based on evolutionary relationships between various organisms.
Major Plant Groups
Algae: Simple, thalloid, autotrophic, and largely aquatic organisms; divided into Chlorophyceae, Phaeophyceae, and Rhodophyceae.
Bryophytes: Known as the "amphibians of the plant kingdom"; include liverworts and mosses that live in moist habitats.
Pteridophytes: The first terrestrial plants to possess vascular tissues (Xylem and Phloem); used for medicinal purposes and as ornamentals.
Gymnosperms: Plants in which the ovules are not enclosed by any ovary wall and remain exposed; include the redwood tree Sequoia.
Angiosperms: Flowering plants where seeds are enclosed within fruits; divided into Dicotyledons and Monocotyledons.
Life Cycles and Alternation of Generations
Gametophytic Phase: The haploid () phase that produces gametes through mitosis.
Sporophytic Phase: The diploid () phase that produces spores through meiosis.
Patterns: Plants exhibit Haplontic, Diplontic, or Haplo-diplontic life cycles depending on the dominant phase.
Classification Systems
Artificial System: Based on gross superficial morphological characters such as habit, color, number, and shape of leaves.
Natural System: Based on natural affinities among organisms, including internal features like ultrastructure, anatomy, embryology, and phytochemistry.
Phylogenetic System: Based on evolutionary relationships between various organisms.
Major Plant Groups
Algae: Simple, thalloid, autotrophic, and largely aquatic organisms; divided into Chlorophyceae, Phaeophyceae, and Rhodophyceae.
Bryophytes: Known as the "amphibians of the plant kingdom"; include liverworts and mosses that live in moist habitats.
Pteridophytes: The first terrestrial plants to possess vascular tissues (Xylem and Phloem); used for medicinal purposes and as ornamentals.
Gymnosperms: Plants in which the ovules are not enclosed by any ovary wall and remain exposed; include the redwood tree Sequoia.
Angiosperms: Flowering plants where seeds are enclosed within fruits; divided into Dicotyledons and Monocotyledons.
Life Cycles and Alternation of Generations
Gametophytic Phase: The haploid () phase that produces gametes through mitosis.
Sporophytic Phase: The diploid () phase that produces spores through meiosis.
Patterns: Plants exhibit Haplontic, Diplontic, or Haplo-diplontic life cycles depending on the dominant phase.
Not only the external features, but also internal features, like cytology, anatomy, evolutionary relationships, and physiological traits, play a role in the classification of plants. Such information helps in discerning points of similarity and differences among species, forming a comprehensive understanding of plant diversity.