Question

35. The success of embryo culture depends on all of these factors except

• a. Agar concentration
• b. Source of amino acids/peptides
• c. Embryo age
• d. Optimum concentrations of auxins:cytokinins

37. Genetic engineering of the Ti-plasmid included

• Removal of ori seqeunces
• Removal of oncogenes
• Removal of T-DNA border sequences

Answer 1

Answer - Option d-Optimum concentrations of auxins:cytokines.

Explanation-These growth regulators are not required, as they induce callus formation, which may obstruct the embryo growth and development.

Embryo culture deals with the sterile isolation and in vitro(in lab conditions) growth of a mature or an immature embryo to develop it ultimately into a viable plant.

Answer 2 - Removal of oncogenes.

For plant transformation, the tumour-inducing genes (oncogenes)  are removed  to make a “disarmed plasmid." After removal of the Agrobacterium , the transformed cells are grown into plants under selection.

Plant transformation vectors are plasmids that are specifically designed for the purpose of generation of transgenic plants.