Teptal cells are very large cells with more than one nucleus. They assist with pollen grain growth and development. Teptal cell undergo endomitosis where the nucleus in the nuclear membrane splits, but cytokinesis does not happen. They become bi / multi nucleate because of this.
Usually the cell are large and have more than one nucleus per cell. The nuclei of teptal cells also split as the sporogenous cells undergo mitosis. Sometimes, this mitosis is not normal due to which many cells of mature teptum becomes multi nucleate. It is also possible to see polyploidy and polyteny at times.

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Tapetal cells becoming bi-nucleate

Tapetal cells in plants undergo a unique process where they become bi-nucleate, which is related to the 8 nucleate 7 celled structure in plants. This process involves several key steps:

Formation of 8 nucleate 7 celled structure
- In the anther of the flower, the pollen mother cell undergoes meiosis to produce haploid microspores.
- Each microspore undergoes mitosis to form a two-celled structure consisting of a generative cell and a tube cell.
- The generative cell then divides to form two sperm cells.
- The tube cell and the generative cell, along with the two sperm cells, make up the 8 nucleate 7 celled structure.

Relation to tapetal cells becoming bi-nucleate
- The tapetal cells play a crucial role in the development of pollen grains within the anther.
- As the pollen grains mature, the tapetal cells undergo changes, including becoming bi-nucleate.
- The bi-nucleate tapetal cells provide essential nutrients and support for the developing pollen grains.
- This process of tapetal cells becoming bi-nucleate is essential for the proper development and maturation of pollen grains.

In summary, the process of tapetal cells becoming bi-nucleate is closely related to the 8 nucleate 7 celled structure in plants and is crucial for the successful development of pollen grains within the anther.