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Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (/ ˌ æ n dʒ i ə ˈ s p ər m iː /). [5] [6] 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.
The fossil history of flowering plants records the development of flowers and other distinctive structures of the angiosperms, now the dominant group of plants on land.The history is controversial as flowering plants appear in great diversity in the Cretaceous, with scanty and debatable records before that, creating a puzzle for evolutionary biologists that Charles Darwin named an "abominable ...
Flowers are modified leaves possessed only by the angiosperms, which are relatively late to appear in the fossil record. The group originated and diversified during the Early Cretaceous and became ecologically significant thereafter. [110] Flower-like structures first appear in the fossil records some ~130 mya, in the Cretaceous. [111]
Flower of Liriodendron tulipifera, a Mesangiosperm. Mesangiospermae is a clade that contains the majority of flowering plants (angiosperms). Mesangiosperms are therefore known as the core angiosperms, in contrast to the three orders of earlier-diverging species known as the basal angiosperms: Nymphaeales (including water lilies), Austrobaileyales (including star anise), and Amborellales.
An endosperm is formed after the two sperm nuclei inside a pollen grain reach the interior of a female gametophyte or megagametophyte, also called the embryonic sac.One sperm nucleus fertilizes the egg cell, forming a zygote, while the other sperm nucleus usually fuses with the binucleate central cell, forming a primary endosperm cell (its nucleus is often called the triple fusion nucleus).
The distinctions between annual and perennial plants are notably evident in agricultural contexts. Despite constituting a minor part of global biomass, annual species stand out as the primary food source for humankind, likely owing to their greater allocation of resources to seed production, thereby enhancing agricultural productivity.
Flowers have long been appreciated for their beauty and pleasant scents, and also hold cultural significance as religious, ritual, or symbolic objects, or sources of medicine and food. Etymology Flower is from the Middle English flour , which referred to both the ground grain and the reproductive structure in plants, before splitting off in the ...
The anthophytes are a paraphyletic grouping of plant taxa bearing flower-like reproductive structures. The group, once thought to be a clade , [ 1 ] contained the angiosperms – the extant flowering plants, such as roses and grasses – as well as the Gnetales and the extinct Bennettitales .