**Group 1: Flowering Plant Characteristics**
– Angiosperms are terrestrial vascular plants with roots, stems, leaves, and seeds.
– Flowers are the unique reproductive organs of flowering plants.
– Reduced gametophytes in male and female parts compared to gymnosperms.
– Endosperm provides food for the developing embryo.
– Xylem in angiosperms is made of vessel elements, unlike gymnosperms.
**Group 2: Diversity of Flowering Plants**
– Largest angiosperms include Eucalyptus gum trees and Shorea faguetiana trees.
– Smallest angiosperms are Wolffia duckweeds.
– Flowering plants can be photosynthetic or parasitic.
– Thrive in diverse environments from deserts to arctic habitats.
– Some can adapt to extreme acid or alkaline conditions.
**Group 3: Reproduction and Development of Flowering Plants**
– Flowers for fertilization and seed development.
– Pollen grains and egg cells are produced in flowers.
– Different pollination strategies and flower structures.
– Double fertilization and embryogenesis process.
– Seed coat, fruit development, and asexual reproduction mechanisms.
**Group 4: Utilization and Interaction with Humans**
– Agriculture relies heavily on angiosperms for food and livestock feed.
– Plants provide materials like wood, fibers, medicines, and beverages.
– Cultural uses in art, literature, and as floral emblems.
– Practical uses in agriculture, food supply, and fiber sources.
– Significant role in providing essential resources for human consumption.
**Group 5: Evolution, Taxonomy, and Conservation of Flowering Plants**
– Estimated 250,000 to 400,000 species of flowering plants.
– Classified into 64 orders and 416 families.
– Dominant group of land plants with explosive diversification.
– Ongoing research on evolution, diversity, and conservation.
– Threatened by habitat loss, climate change, and human activities.
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (/ˌændʒiəˈspərmiː/), commonly called angiosperms. They include all forbs (flowering plants without a woody stem), grasses and grass-like plants, a vast majority of broad-leaved trees, shrubs and vines, and most aquatic plants. The term "angiosperm" is derived from the Greek words ἀγγεῖον / angeion ('container, vessel') and σπέρμα / sperma ('seed'), meaning that the seeds are enclosed within a fruit. They are by far the most diverse group of land plants with 64 orders, 416 families, approximately 13,000 known genera and 300,000 known species. Angiosperms were formerly called Magnoliophyta (/mæɡˌnoʊliˈɒfətə, -əˈfaɪtə/).
Flowering plant Temporal range:
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Spermatophytes |
Clade: | Angiosperms |
Groups (APG IV) | |
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Synonyms | |
Angiosperms are distinguished from the other seed-producing plants, the gymnosperms, by having flowers, xylem consisting of vessel elements instead of tracheids, endosperm within their seeds, and fruits that completely envelop the seeds. The ancestors of flowering plants diverged from the common ancestor of all living gymnosperms before the end of the Carboniferous, over 300 million years ago. In the Cretaceous, angiosperms diversified explosively, becoming the dominant group of plants across the planet.
Agriculture is almost entirely dependent on angiosperms, and a small number of flowering plant families supply nearly all plant-based food and livestock feed. Rice, maize, and wheat provide half of the world's calorie intake, and all three plants are cereals from the Poaceae family (colloquially known as grasses). Other families provide materials such as wood, paper and cotton, and supply numerous ingredients for traditional and modern medicines. Flowering plants are also commonly grown for decorative purposes, with certain flowers playing a significant role in many cultures.
Out of the "Big Five" extinction events in Earth's history, only the Cretaceous–Paleogene extinction event had occurred while angiosperms dominated plant life on the planet. Today, the Holocene extinction affects all kingdoms of complex life on Earth, and conservation measures are necessary to protect plants in their habitats in the wild (in situ), or failing that, ex situ in seed banks or artificial habitats like botanic gardens. Otherwise, around 40% of plant species may become extinct due to human actions such as habitat destruction, introduction of invasive species, unsustainable logging and collection of medicinal or ornamental plants. Further, climate change is starting to impact plants and is likely to cause many species to become extinct by 2100.