Sunday, July 28, 2019

Plant Biology questions ---angiosperm questions Assignment

Plant Biology questions ---angiosperm questions - Assignment Example Cotyledons are tiny structures found in seed and they form leaves during their later developments. Nonetheless, among the angiosperm species include dandelions with genus Taraxacum in the family Asteraceae. Additionally, there is the Orchis adenocheilae  species of the Orchis genus in the family of Orchis or the orchidaceae. Dandelions (Taraxacum officinale) are a weed that is common in North America. They are nuisance in lawns; however, they also appear in garden beds. They are dark green with jagged edged leaves that are arranged in circular rosettes (Martin, 2005; PG. 05). Their stems usually rise from rosettes with bright yellow tops. They can be described as daisy shaped flowers that often open in mid spring after which they quickly puff white seed heads. Each seed has parachute that flies off with wind; thus, they are dispersed by wing (Dodson, n.d.; PG. 01). These seeds germinate eagerly; however, they take time to have footholds. They often bloom in nearly all seasons and r eadily survive winter that affects nearly the entire North America (Wachman, n.d.; 01). They have deep taproots which readily sprout new leaves if root is not killed or removed. When damaged, the entire plant seep milky sap. Alternatively, the Orchis adenocheilae  has different characteristics that make them distinguished from other flowers. The sexual portions of Orchis adenocheilae  are different from other flowers in that they are characterized by reduced number of sexual portions (Jacquemyn et al. 2011; pg. 01). The general flower is characterized by style, filaments, anthers, and stigma, features that are reduced in Orchis adenocheilae  and fused into a single structured referred to column. Orchids have only one anther that is situated at the apex of their column (Yang, 2011; PG. 01). Additionally, an orchid’s ovary has three carpels that fused to an outward evidence of existing three ridges that are found on the outside of seed pods. Notably, a mature orchid seed opens usually opens about the middle juncture between the lines. Therefore, the seeds of this flower are dispersed through self dispersion. The ovules are often arranged in the inside of the ridges of the ovary where they do not develop until the flower is pollinated; therefore, the delay between pollination and opening up of the dry pod. Finally, it is worth noting that petals and sepals are quite distinct in orchids and have remained the main distinction between them and other flowers (Garden and Landscape Tips, n.d.; pg. 01). Their petals are referred to labellum or lip. Two or up to three of these sepals are usually joined to a column and their fertile stamens are usually located on one side on the flower. Finally, it is worth noting that orchids depend on self and cross- pollination. Nonetheless, it is worth noting that orchids in hot regions depend on cross pollination that is facilitated by different types of bees while those in cold regions depend on self pollination (Dodson , n.d.; PG. 01). However, they depend on mycorrhizal fungi to complete their life cycle especially at their early stage of development. The Orchids is the largest angiosperm and has nearly two thousand species including the Orchis adenocheilae. In the communities in the ecological system, species usually interact with one another to form a complex and a highly structured network. These network structures usually vary

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