Question

If $Ca$ of $2$-celled proembryo divides longitudinally and the $Ca$ and $Cb$ both contribute to the development of embryo, this type of embryogeny would be called as

• A. onagrad type
• B. asterad type
• C. solanad type
• D. Both (a) and (b)

Answer 1

Answer: (B)

When both apical cell $(Ca)$ and basal cell $(Cb)$ of the $2$ celled proembryo divides longitudinally, the type of embryo would be asterad type, eg, Asteraceae, Balsaminaceae Violaceae, Vitacae.
In onagrad type of embryo development, the basal cell plays a minor role or none in development of embryo proper, eg, Annonaceae, Brassicaceae, Pedaliaceae, Ranunculaceae etc.
In solanad type of embryo development, $2$ celled proembryo divides transversely and the basal cell either plays a minor role or no role in its development. In this type, basal cells usually form a suspensor, eg, Campanulaceae, Linaceae, Solanaceae, Theaceae.