merisztémát

Merisztéma is a term used in botany to describe actively dividing plant tissues. These regions are characterized by small, thin-walled cells that are undifferentiated or incompletely differentiated. Meristematic cells are typically isodiametric in shape and possess dense cytoplasm and large nuclei. They lack vacuoles or have very small ones, and their cell walls are generally flexible, allowing for rapid expansion.

The primary function of meristematic tissue is to produce new cells through mitosis, which then differentiate to form various plant organs and tissues. Meristems are responsible for plant growth in length (primary growth) and in girth (secondary growth). There are two main types of meristems: apical meristems and lateral meristems. Apical meristems are found at the tips of roots and shoots and are responsible for increasing the plant's length. Lateral meristems, such as the vascular cambium and cork cambium, are found in cylinders along the length of stems and roots and are responsible for secondary growth, leading to an increase in diameter.

Intercalary meristems are another type, often found in grasses and other monocots, located at the bases of leaf nodes or internodes, allowing for regrowth after being cut or grazed. The continuous division of cells within meristems fuels the development of the plant, enabling it to reach maturity, reproduce, and adapt to its environment.