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The opposite of homologous organs are analogous organs which do similar jobs in two taxa that were not present in their most recent common ancestor but rather evolved separately. For example, the wings of insects and birds evolved independently in widely separated groups, and converged functionally to support powered flight, so they are analogous.
Plant morphology treats both the vegetative structures of plants, as well as the reproductive structures. The vegetative (somatic) structures of vascular plants include two major organ systems: (1) a shoot system, composed of stems and leaves, and (2) a root system. These two systems are common to nearly all vascular plants, and provide a ...
Vertebrate wings are partly homologous (from forelimbs), but analogous as organs of flight in (1) pterosaurs, (2) bats, (3) birds, evolved separately. Birds and bats have homologous limbs because they are both ultimately derived from terrestrial tetrapods , but their flight mechanisms are only analogous, so their wings are examples of ...
Palm trees form are in unrelated plants: cycads (from the Jurassic period) and older tree ferns. [231] Flower petals came about independently in a number of different plant lineages. [232] Bilateral flowers, with distinct up-down orientation, came about independently in a number of different plants like: violets, orchids and peas. [233] [234]
Versuch die Metamorphose der Pflanzen zu erklären, known in English as Metamorphosis of Plants, was published by German poet and philosopher Johann Wolfgang von Goethe in 1790. In this work, Goethe essentially discovered the (serially) homologous nature of leaf organs in plants, from cotyledons, to photosynthetic leaves, to the petals of a flower.
Plant structures or organs fulfil specific functions, and those functions determine the structures that perform them. Among terrestrial (land) plants, the vascular and non-vascular plants (Bryophytes) evolved independently in terms of their adaptation to terrestrial life and are treated separately here (see Bryophytes). [6]
These buds give rise to gametophores (0.5–5.0 mm [18]), more complex structures bearing leaf-like structures, rhizoids, and the sexual organs: female archegonia and male antheridia. P. patens is monoicous, meaning that male and female organs are produced in the same plant. If water is available, flagellate sperm cells can swim from the ...
Homogamy refers to the maturation of male and female reproductive organs (of plants) at the same time, which is also known as simultaneous or synchronous hermaphrodism and is the antonym of dichogamy. Many flowers appear to be homogamous but some of these may not be strictly functionally homogamous, because for various reasons male and female ...