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Evolutionary history of plants. A late Silurian sporangium, artificially colored. Green: A spore tetrad. Blue: A spore bearing a trilete mark – the Y -shaped scar. The spores are about 30–35 μm across. The evolution of plants has resulted in a wide range of complexity, from the earliest algal mats of unicellular archaeplastids evolved ...
Animals mainly have bilateral or mirror symmetry, as do the leaves of plants and some flowers such as orchids. [30] Plants often have radial or rotational symmetry, as do many flowers and some groups of animals such as sea anemones. Fivefold symmetry is found in the echinoderms, the group that includes starfish, sea urchins, and sea lilies. [31]
Photosynthesis ( / ˌfoʊtəˈsɪnθəsɪs / FOH-tə-SINTH-ə-sis) [ 1] is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabolism.
Mucilage is a thick gluey substance produced by nearly all plants and some microorganisms. These microorganisms include protists which use it for their locomotion. The direction of their movement is always opposite to that of the secretion of mucilage. [ 1] It is a polar glycoprotein and an exopolysaccharide.
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 ...
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] 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 .
A flower, also known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae ). Flowers consist of a combination of vegetative organs – sepals that enclose and protect the developing flower. These petals attract pollinators, and reproductive organs that produce gametophytes, which in ...
t. e. On the Origin of Species (or, more completely, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life) [ 3] is a work of scientific literature by Charles Darwin that is considered to be the foundation of evolutionary biology. It was published on 24 November 1859. [ 4]