Lateral Meristem
Explanation
Meristematic tissues consist of actively dividing cells responsible for plant growth. Based on their location within the plant body, meristems are classified into three types: Apical, Intercalary, and Lateral. Cambium is a specific type of meristem associated with secondary growth.
Detailed Analysis
- Apical Meristem: Located at the tips of roots and shoots, these are responsible for primary growth, specifically the elongation of the plant axis. They are not referred to as cambium.
- Intercalary Meristem: Found between mature tissues (e.g., at the base of leaves or internodes in grasses), these aid in the regeneration of parts removed by grazing herbivores. They are also part of the primary growth system.
- Lateral Meristem: These occur in the mature regions of roots and shoots, typically arranged parallel to the longitudinal axis of the organ. They are responsible for secondary growth, which increases the girth or thickness of the plant. The Vascular Cambium and Cork Cambium are the primary examples of lateral meristems. Therefore, the term 'Cambium' specifically refers to Lateral Meristem.
- Permanent Tissue: These are tissues derived from meristems that have lost the ability to divide and have attained a specific form and function (e.g., Parenchyma, Xylem). Cambium is an actively dividing tissue, not a permanent one.
Key Takeaway
Cambium is a Lateral Meristem responsible for the secondary growth (increase in girth) of dicotyledonous roots and stems.