Details of development of embryo in dicots were first studied in
Answers
Answered by
2
Development of embryo in dicotyledon:
The normal type of dicot embryo development has been studied in Shepherd's purse (Capsella bursa pastoris) of family Cruciferae. This is called as crucifer or onagrad type of embryo development.
This development of embryo is endoscopic i.e., apex is downward or towards inside. The first division of zygote is transverse which produces a basal cell (cb) towards the micropyle and a terminal cell (ca) towards chalaza. The basal cell divides by transverse division and the terminal cell by a longitudinal division resulting 4 celled T-shaped proembryo.
The two basal cells divide by transverse division and form 6-10 celled suspensor. The upper most cell of the suspensor is vasicular cell and lowest cell is called hypophysis which forms radicle and root cap. The two apical cells first divide by longitudinal division (at right angle to first one) and then by transverse and periclinal division. So sixteen celled globular embryo is produced.
Due to differentiation of cotyledons globular embryo becomes heart shaped. Mature embryo in dicots consists of two lateral cotyledons, terminal plumule or stem tip and radicle or root tip.
The normal type of dicot embryo development has been studied in Shepherd's purse (Capsella bursa pastoris) of family Cruciferae. This is called as crucifer or onagrad type of embryo development.
This development of embryo is endoscopic i.e., apex is downward or towards inside. The first division of zygote is transverse which produces a basal cell (cb) towards the micropyle and a terminal cell (ca) towards chalaza. The basal cell divides by transverse division and the terminal cell by a longitudinal division resulting 4 celled T-shaped proembryo.
The two basal cells divide by transverse division and form 6-10 celled suspensor. The upper most cell of the suspensor is vasicular cell and lowest cell is called hypophysis which forms radicle and root cap. The two apical cells first divide by longitudinal division (at right angle to first one) and then by transverse and periclinal division. So sixteen celled globular embryo is produced.
Due to differentiation of cotyledons globular embryo becomes heart shaped. Mature embryo in dicots consists of two lateral cotyledons, terminal plumule or stem tip and radicle or root tip.
Similar questions