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Pollinator Exclusion Experiment
Pollinator exclusion experiments are experiments used by ecologists to determine the effectiveness of putative plant pollination vectors. Essentially, certain pollinators are prevented from visiting certain flowers, and observations are then made on which flowers develop seeds. If the exclusion of a certain class of visitor prevents or greatly reduces flower fertilisation rates, then it can be concluded that that class of visitor plays an important role in pollination. There are various methods for excluding pollinators. A cage may exclude nectarivorous birds and mammals but allow access by insects. A net may exclude all but the smallest animals, yet permit wind-pollination. Insect repellent may prevent visits by insects whilst allowing access by birds and mammals. Bags may be used to prevent all but autogamous Autogamy, or self-fertilization, refers to the fusion of two gametes that come from one individual. Autogamy is predominantly observed in the form of self-pollination, a re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecology
Ecology () is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overlaps with the closely related sciences of biogeography, evolutionary biology, genetics, ethology, and natural history. Ecology is a branch of biology, and it is not synonymous with environmentalism. Among other things, ecology is the study of: * The abundance, biomass, and distribution of organisms in the context of the environment * Life processes, antifragility, interactions, and adaptations * The movement of materials and energy through living communities * The successional development of ecosystems * Cooperation, competition, and predation within and between species * Patterns of biodiversity and its effect on ecosystem processes Ecology has practical applications in conservation biology, wetland management, natural resource managemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollination
Pollination is the transfer of pollen from an anther of a plant to the stigma of a plant, later enabling fertilisation and the production of seeds, most often by an animal or by wind. Pollinating agents can be animals such as insects, birds, and bats; water; wind; and even plants themselves, when self-pollination occurs within a closed flower. Pollination often occurs within a species. When pollination occurs between species, it can produce hybrid offspring in nature and in plant breeding work. In angiosperms, after the pollen grain (gametophyte) has landed on the stigma, it germinates and develops a pollen tube which grows down the style until it reaches an ovary. Its two gametes travel down the tube to where the gametophyte(s) containing the female gametes are held within the carpel. After entering an ovum cell through the micropyle, one male nucleus fuses with the polar bodies to produce the endosperm tissues, while the other fuses with the ovule to produce the embr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insect Repellent
An insect repellent (also commonly called "bug spray") is a substance applied to skin, clothing, or other surfaces to discourage insects (and arthropods in general) from landing or climbing on that surface. Insect repellents help prevent and control the outbreak of insect-borne (and other arthropod-bourne) diseases such as malaria, Lyme disease, dengue fever, bubonic plague, river blindness, and West Nile fever. Pest animals commonly serving as vectors for disease include insects such as flea, fly, and mosquito; and ticks (arachnids). Some insect repellents are insecticides (bug killers), but most simply discourage insects and send them flying or crawling away. Nearly any would be fatal upon reaching the median lethal dose, but classification as an insecticide implies death even at lower doses. Effectiveness Synthetic repellents tend to be more effective and/or longer lasting than "natural" repellents. For protection against mosquito bites, the U.S. Centers for Diseas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollination Bags
Pollination bags, sometimes called crossing bags, isolation bags or exclusion bags, are containers made of various different materials for the purpose of controlling pollination for plants. Characteristics of pollination Bags Pollination bags are designed to fit well over the inflorescence or individual flowers of a plant type. The size, shape and strength of bag should ensure that there is no contact with flowers to avoid development of diseases and physical hindrances in seed development. The size of bag will vary with the size of inflorescence to be covered. Pollination bags may be 2D or 3D. The 3D bags have a gusset for expansion to avoid contact between the plant and the bag. Sometimes pollination bags may have a window to allow examination of inflorescence without removing the bag. Bags with a flap over the window, when provided, protects from strong sunlight. Most pollination bags are produced by general paper bag manufacturers which have branched out into providing pollinat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autogamy
Autogamy, or self-fertilization, refers to the fusion of two gametes that come from one individual. Autogamy is predominantly observed in the form of self-pollination, a reproductive mechanism employed by many flowering plants. However, species of protists have also been observed using autogamy as a means of reproduction. Flowering plants engage in autogamy regularly, while the protists that engage in autogamy only do so in stressful environments. Occurrence Protists ''Paramecium aurelia'' ''Paramecium aurelia'' is the most commonly studied protozoan for autogamy. Similar to other unicellular organisms, ''Paramecium aurelia'' typically reproduce asexually via binary fission or sexually via cross-fertilization. However, studies have shown that when put under nutritional stress, ''Paramecium aurelia'' will undergo meiosis and subsequent fusion of gametic-like nuclei. This process, defined as hemixis, a chromosomal rearrangement process, takes place in a number of steps. First, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecological Experiments
Ecology () is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overlaps with the closely related sciences of biogeography, evolutionary biology, genetics, ethology, and natural history. Ecology is a branch of biology, and it is not synonymous with environmentalism. Among other things, ecology is the study of: * The abundance, biomass, and distribution of organisms in the context of the environment * Life processes, antifragility, interactions, and adaptations * The movement of materials and energy through living communities * The successional development of ecosystems * Cooperation, competition, and predation within and between species * Patterns of biodiversity and its effect on ecosystem processes Ecology has practical applications in conservation biology, wetland management, natural resource management (ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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