Question

Explain the different types of meristems based on their positions.

Answer 1

Hint: Meristem is tissue found in plants that contain undifferentiated cells which are responsible for cell division. Meristem cells can be converted into different types of tissues and organs that occur in the body of plants. The term meristem was first used by Carl Wilhelm von Nageli in 1858.

Complete answer:
Division of meristematic cells helps in formation of new cells which help in formation of new tissues and organs. These cells are packed firmly together without the presence of intercellular spaces. There are three types of meristem which are differentiated based on position of the meristem are apical meristem, intercalary meristem and lateral meristem. These meristems perform different activities based on their location.

Apical meristem is located at the tip of roots, stem and branches. It helps to increase in the length of the plant as it is present on the top and divided into three zones- protoderm, procambium and ground meristem. Epidermal tissues arise from protoderm, primary vascular tissues rise from procambium and ground meristem gives rise to cortex and pith.

Intercalary meristem is present in the nodal region and prominently found in monocotyledon. It originates from apical meristem and is responsible for internodes elongation. Lateral meristem is present along the longitudinal axis of stem and root. Vascular cambium and cork cambium are examples of lateral meristem.

Note: The other meristem is primary meristem and secondary meristem and the above mentioned types of meristem are of apical meristem. Another type of meristem is floral meristem and they perform various activities that help in overall functioning of the plant body.