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When cells on one side of a stem grow longer and faster than cells on the other side, the stem will bend to the side of the slower growing cells as a result. This directional growth can occur via a plant's response to a particular stimulus, such as light ( phototropism ), gravity ( gravitropism ), water, ( hydrotropism ), and physical contact ...
The formation of woody tissue is an example of secondary growth, a change in existing tissues, in contrast to primary growth that creates new tissues, such as the elongating tip of a plant shoot. The process of wood formation ( lignification ) is commonest in the spermatophytes (seed bearing plants) and has evolved independently a number of times.
The normal lifespan of plant cells is one to three years. Stems have cells called meristems that annually generate new living tissue. Photosynthesis. Stems have two pipe-like tissues called xylem and phloem. The xylem tissue arises from the cell facing inside and transports water by the action of transpiration pull, capillary action, and root ...
A leaf (pl.: leaves) is a principal appendage of the stem of a vascular plant, [1] usually borne laterally above ground 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]
Prickles on a blackberry branch. In plant morphology, thorns, spines, and prickles, and in general spinose structures (sometimes called spinose teeth or spinose apical processes), are hard, rigid extensions or modifications of leaves, roots, stems, or buds with sharp, stiff ends, and generally serve the same function: physically defending plants against herbivory.
The upper angle between one part of a plant and another, e.g. the stem and a leaf. axile On an axis; of a placenta, on the central axis of the ovary. axillary Borne in or arising from the axil, usually referring to the axil of a leaf. axis The main stem of a whole plant or inflorescence; also, the line along which this stem extends.
In addition to growth by cell division, a plant may grow through cell elongation. This occurs when individual cells or groups of cells grow longer. Not all plant cells grow to the same length. When cells on one side of a stem grow longer and faster than cells on the other side, the stem bends to the side of the slower growing cells as a result.
Cells in the meristem can develop into all the other tissues and organs that occur in plants. These cells continue to divide until they differentiate and then lose the ability to divide. Thus, the meristems produce all the cells used for plant growth and function. [3] At the tip of each stem and root, an apical meristem adds cells to their length