Search results
Results from the WOW.Com Content Network
The genus is distinguished from other genera in tribe Astereae mainly by the structure of the fruit. These achenes or cypselas are roughly club-shaped but usually incurved and flattened. They often have a membranous rim or wing around the edge that is sometimes wavy or fringed.
The latter phase has been modelled using the ABC model, which describes the biological basis of the process from the perspective of molecular and developmental genetics. [citation needed] A diagram illustrating flower development in Arabidopsis. An external stimulus is required in order to trigger the differentiation of the meristem into a ...
Flower under natural light (left) and under ultraviolet light (right) showing the nectar guides which are not visible to the human eye. The corolla is the inner whorl of the perianth and the one that surrounds the fertile whorls of the flower. It is composed of petals, which are generally larger than the sepals and are colored.
Anatomy of a flower. A flower's anatomy, as defined by the presence of a series of organs (sepals, petals, stamens and carpels) positioned according to a given pattern, facilitate sexual reproduction in flowering plants. The flower arises from the activity of three classes of genes, which regulate floral development: [8]
Different models of flower development like the fading boundaries model, or the overlapping-boundaries model which propose non-rigid domains of expression, may explain these architectures. [68] There is a possibility that from the basal to the modern angiosperms, the domains of floral architecture have gotten more and more fixed through evolution.
Taraxacum officinale, the dandelion or common dandelion, [6] is a herbaceous perennial flowering plant in the daisy family, Asteraceae. The common dandelion is well known for its yellow flower heads that turn into round balls of many silver-tufted fruits that disperse in the wind. These balls are called "clocks" in both British and American ...
A fruit is the mature, ripened ovary of a flower following double fertilization in an angiosperm.Because gymnosperms do not have an ovary but reproduce through fertilization of unprotected ovules, they produce naked seeds that do not have a surrounding fruit, this meaning that juniper and yew "berries" are not fruits, but modified cones.
The ABC model of flower development. The first step of the transition is the transformation of the vegetative stem primordia into floral primordia. This occurs as biochemical changes take place to change the cellular differentiation of leaf, bud and stem tissues into tissue that will grow into the reproductive organs.