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  2. Phototropism - Wikipedia

    en.wikipedia.org/wiki/Phototropism

    Both root tips and most stem tips exhibit positive phototropism to red light. [citation needed] Cryptochromes are photoreceptors that absorb blue/ UV-A light, and they help control the circadian rhythm in plants and timing of flowering. Phytochromes are photoreceptors that sense red/far-red light, but they also absorb blue light; they can ...

  3. Leaf - Wikipedia

    en.wikipedia.org/wiki/Leaf

    A leaf (pl.: leaves) is a principal appendage of the stem of a vascular plant, [1] usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", [2][3] while the leaves, stem, flower, and fruit collectively form the shoot system. [4]

  4. Coleoptile - Wikipedia

    en.wikipedia.org/wiki/Coleoptile

    The majority of the tissue remains ungreening throughout the lifecycle (right). Coleoptile is the pointed protective sheath covering the emerging shoot in monocotyledons such as grasses in which few leaf primordia and shoot apex of monocot embryo remain enclosed. The coleoptile protects the first leaf as well as the growing stem in seedlings ...

  5. Thigmotropism - Wikipedia

    en.wikipedia.org/wiki/Thigmotropism

    Thigmotropism. Redvine (Brunnichia ovata) tendrils coil upon contact. In plant biology, thigmotropism is a directional growth movement which occurs as a mechanosensory response to a touch stimulus. Thigmotropism is typically found in twining plants and tendrils, however plant biologists have also found thigmotropic responses in flowering plants ...

  6. Cotyledon - Wikipedia

    en.wikipedia.org/wiki/Cotyledon

    Cotyledon from a Judas-tree (Cercis siliquastrum, a dicot) seedling Comparison of a monocot and dicot sprouting. The visible part of the monocot plant (left) is actually the first true leaf produced from the meristem; the cotyledon itself remains within the seed Schematic of epigeal vs hypogeal germination Peanut seeds split in half, showing the embryos with cotyledons and primordial root Two ...

  7. Cutting (plant) - Wikipedia

    en.wikipedia.org/wiki/Cutting_(plant)

    A plant cutting is a piece of a plant that is used in horticulture for vegetative (asexual) propagation. A piece of the stem or root of the source plant is placed in a suitable medium such as moist soil. If the conditions are suitable, the plant piece will begin to grow as a new plant independent of the parent, a process known as striking.

  8. Meristem - Wikipedia

    en.wikipedia.org/wiki/Meristem

    The inner L3 layer is called the corpus. Cells in the L1 and L2 layers divide in a sideways fashion, which keeps these layers distinct, whereas the L3 layer divides in a more random fashion. In cell biology, the meristem is a type of tissue found in plants. It consists of undifferentiated cells (meristematic cells) capable of cell division.

  9. Gravitropism - Wikipedia

    en.wikipedia.org/wiki/Gravitropism

    As a consequence of this, curved growth occurs and the root is directed downwards. [3] Root growth occurs by division of stem cells in the root meristem located in the tip of the root, and the subsequent asymmetric expansion of cells in a shoot-ward region to the tip known as the elongation zone. Differential growth during tropisms mainly ...