Class 11th, biology, ch. – 3, part – 1

ANGIOSPERM (Flowering plants)

These are the most advanced plants, characterized by the presence of flower, covered ovules and seeds. Angiosperms are the largest group of plants on Earth. There are approximately 270,000 known species alive today. There’s probably one nearby right now. These form the largest group of the plant kingdom, containing about 300 families, 8000 genera and about 300,000 species. These are the highest evolved plants on this earth. From cretaceous period, the angiosperms eclipsed all other vegetation and now they are the most dominant plants. They are found almost everywhere in all possible habitats. Angiosperms include all varieties of plants such as hydrophytes, xerophytes, epiphytes, parasites, saprophytes, insectivorous, symbionts and mangroves etc.

Characteristic features of angiosperms

  1. Presence of flower is the most striking feature of angiosperms. It contains the sex organs of the plant.
  2. Ovules are covered and are present inside the ovary.
  3. Pollen grains are received by the stigma of the carpel, so maturation of pollen grain (male gametophyte) takes place on stigma.
  4. Double fertilization (syngamy and triple fusion) is also characteristic only to angiosperms.