Pollination

Pollination is the process by which pollen is transferred in the reproduction of plants, thereby enabling fertilization and sexual reproduction. In spite of a common perception that pollen grains are gametes, like the sperm cells of animals, this is incorrect; pollination is a phase in the alternation of generations: each pollen grain is a male haploid plant, a gametophyte, adapted to being transported to the female gametophyte, where it can achieve fertilization by producing the male gamete (or gametes, in the process of double fertilization). As such the Angiosperm successful pollen grain (gametophyte) containing the male gametes (sperm) gets transported to the stigma, where it germinates and its pollen tube grows down the style to the ovary. Its two gametes travel down the tube to where the gametophyte(s) containing the female gametes are held within the carpel. One nucleus fuses with the polar bodies to produce the endosperm tissues, and the other with the ovum to produce the embryo[1][2] Hence the term: "double fertilization". In gymnosperms the ovule is not contained in a carpel, but exposed on the surface of a dedicated support organ such as the scale of a cone, so that the penetration of carpel tissue is unnecessary. Details of the process vary according to the division of Gymnosperms in question. The receptive part of the carpel is called a stigma in the flowers of angiosperms. The receptive part of the gymnosperm ovule is calle

the micropyle. Pollination is a necessary step in the reproduction of flowering plants, resulting in the production of offspring that are genetically diverse. The study of pollination brings together many disciplines, such as botany, horticulture, entomology, and ecology. The pollination process as an interaction between flower and vector was first addressed in the 18th century by Christian Konrad Sprengel. It is important in horticulture and agriculture, because fruiting is dependent on fertilisation, which is the result of pollination. In science, a process is every sequence of changes of a real object/body which at least in principle is observable using the scientific method. Therefore, all sciences analyze and model processes. Processes are always properties of dynamic systems; they are characterized by such system attributes as variables and parameters. Every process model has distinguished input and output variables, and it can be autonomous or controlled. The recognition of a process is an arbitrary subjective mental operation/event because it depends on different circumstances: the observer's goal, perception and conceptualization tools. There are numerous taxonomies of processes, and, roughly speaking, they are divided into: continuous and discrete, stable and not stable, convergent or not convergent, cyclic and not cyclic, linear and not linear. They are grouped according to the name of the domain in which they are analyzed.