Meristem

A meristem is a group of undifferentiated cells that are capable of undergoing division and growth in plants. It is the region of the plant that is actively growing and dividing to form new tissues.

The word meristem comes from the Greek word “meristos,” meaning “divisible.”

Pinching or clipping off the plant’s meristem encourages the mother plant to produce two or more shots. The action of clipping enables these meristem tissues to rapidly start the cell division and create new growth.

These meristem cells stand as the source to many other cells like shoots, roots, and flowers. These cells rapidly differentiate, specialize, and form various parts of the plant. If meristem cells become flowers, they will no longer be able to reproduce like they would if they became leaves, stems, or roots.

Meristems are classified by their location in the plant as:

  • Apicals: These are located at the root and shoot tips. They are considered the primary meristems and they form the shoot or root of a plant
  • Laterals: These are located in the vascular and cork cambia. They are considered the secondary meristems and are responsible for stem thickness and girth
  • Intercalaries: These are located in the internodes, or stem regions.

Characteristics of meristem cells include:

  • A thin and flexible cell wall, as a rigid cell wall would affect its ability to actively divide
  • Rectangular, oval, spherical, or polygonal shape
  • A lack of vacuoles
  • Containing dense cytoplasm