Merisztimát

Merisztimát is a botanical term referring to a tissue in plants responsible for growth. This tissue is characterized by actively dividing cells, enabling the plant to increase in size and develop new organs like leaves, stems, and roots. Meristematic tissues are found in specific regions of the plant, primarily at the tips of shoots and roots, and also in lateral positions like the vascular cambium and cork cambium.

There are two main types of meristematic tissue: apical meristems and lateral meristems. Apical meristems are located at the apex, or tip, of the root and shoot systems. Their activity leads to primary growth, which is an increase in length. This is crucial for the plant to reach sunlight and access water and nutrients from the soil. Lateral meristems, on the other hand, are responsible for secondary growth, which is an increase in girth or thickness. The vascular cambium produces secondary xylem and phloem, contributing to wood formation, while the cork cambium produces cork, forming the outer bark.

The cells within meristematic tissues are typically small, isodiametric, and thin-walled. They possess dense cytoplasm and large, prominent nuclei, but they lack large central vacuoles. These cells divide repeatedly through mitosis, producing new cells that can then differentiate into various specialized cell types that form the permanent tissues of the plant. This continuous division and differentiation are fundamental to plant development and adaptation.