Question

Suspensor of the embryo is formed by
(a)Basal cells
(b)Apical cell
(c)Terminal cell
(d)Hypophysis

Answer 1

The suspensor provides physical support and nutrition in early embryogenesis. They act as growth regulators to the developing embryo. They undergo asymmetric division of the zygote. They undergo cell death and do not present in the mature seed.

Complete answer:
Suspensor of the embryo is formed by basal cells. They are the structures found in certain fungi and plants. They are found in zygotes in the angiosperms in plants. The suspensor cell divides transversally in dicots two forms of filamentous suspensor of 6 to 10 cells. The suspensor towards the micropylar becomes swollen and starts functioning as a haustorium. It has a wall in growth which is similar to those of a transfer cell. In angiosperms seeds, the development of embryos involves asymmetrical division of unicellular embryos which induces polarity. The suspenders are filamentous in a structure which functions as holding the two strains of hyphae in fungi. The suspensor is believed to be a supporting structure during plant embryo development. It pushes the embryo properly into the endosperm cavity. It connects the embryo to the surrounding maternal and endosperm tissues which facilitate the transfer of nutrients and plant hormones.
Apical cells: Apical cells divide repeatedly to form new cells and the cell division takes place along the rear faces. It never takes place along the front face. It contains one front face and up to three rear faces. The gametophytic growth in bryophytes is under the control of apical cells. Gametophytic growth is due to apical cells. They vary in shape and can have up to four cutting faces. Most of the plant embryo is developed from the apical cells.
Hypophysis: It is found at the interface between the suspensor and the embryo. It gives rise to some of the root cells in many species. It orients the absorptivity service of the embryo towards its food source in gymnosperms and angiosperms. It appears to serve as a nutrient for developing embryos.
So, the correct answer is 'Basal cells'.

Note: Suspensor is a good source of the hormone. In runner beans, the young embryo can survive without a suspensor if they are supplemented with growth hormone which is gibberellic acid. Apical-based polarity is the key achievement of embryogenesis which is useful to consider the suspensor and embryo develop unique morphologies.