Differences between Tapetum and Integumentary tapetum

Tapetum is the innermost layer of anther wall and attains its maximum development at the tetrad stage of microsporogenesis and its completely surrounds the sporogenous tissue.
Integumentary tapetum also known as Endothelium is a part of ovule which derived from innermost layer of integument and nutritive in function and cover the entire embryo sac.

1. DIFFERENCE BETWEEN TAPETUM AND INTEGUMENTARY TAPETUM

2. Introduction Tapetum is the innermost layer of anther wall and attains its maximum development at the tetrad stage of microsporogenesis. It completely surrounds the sporogenous tissue and is of considerable physiological importance because all the food material to the sporogenous tissue must pass through it. It is composed of a single layer of cells having dense cytoplasm and prominent nuclei. Tapetum is od dual origin in angiosperms. Based on its behaviour, tapetum is of two types: Amoeboid tapetum and Secretory tapetum. Tapetum

3. Plants belonging to the sympetalae with unitegmic , tenuinucellate ovules, the nucellus degenerates at an early stage of ovule development and the innermost layer of the integument becomes specialized to perform the nutritive function for the embryo sac. This specialized tissue, present around the embryo sac is called endothelium. Occurrence of endothelium has been observed in 65 families of dicots. Endothelium usually single layered but in Asteraceae it is multi-layered. Interesting feature of the endothelial cells is the development of adventive embryos . In Begoniaceae, Droseraceae and Fabaceae the persistent nucellar cells form an endothelium like tissue. Because of its different origin it has been called false endothelium. Integumentary tapetum

4. Differences between Tapetum and Integumentary tapetum Tapetum It is the part of wall layer of anther(innermost layer of anther). Have dual origin, tapetal portion toward outside contributed by parietal layer and inner portion derived from connective tissue. Completely surround sporogenous tissue. Integumentary tapetum Part of ovule. Derived from innermost layer of integument. Its surround the entire embryo sac.

5. Tapetum Single layered. In some species , tapetal cell of different origin may also differ morphologically so they re called as Dimorphic tapetum. It is of two types, Amoeboid tapetum and Secretory tapetum. Example- Tradescantia and Alectra thomsoni. Integumentary tapetum Usually single layered but multi-layered in Asteraceae. Also known as Endothelium and in Begoniaceae , Droseraceae and Elatinaceae persistent nucellar cells form an endothelium like tissue, because of its different origin has been called false endothelium. No further types Example- Glossocardia Bosvallia and Volutarella ramosa