These nematodes, sold under the names of Scanmask and Nemasys, are microscopic, wormlike creatures that will destroy the fungus gnats but are not harmful to people, pets, plants, or earthworms. These products can be used whenever the soil is not frozen and will keep working for many months.
Vegetative structures. There are three levels of integrated organization in the vegetative plant body: organ, tissue system, and tissue. The organs of the plantâthe roots, stems, and leavesâare composed of tissue systems (dermal tissue, ground tissue, and vascular tissue; see below Tissue systems).
Organ Systems in plants Our water has traveled up the Xylem express up the stem here, to the leaves. Leaves are a plants food-producing organs, ORGANS are the third level of organization. For a plant to make sugars (food) out of water, carbon dioxide and sunlight the process of photosynthesis happens.