Define the following terms:(a) Aestivation (b) Placentation (c) Actinomorphic (d) Zygomorphic (e) Superior ovary (f) Perigynous flower (g) Epipetalous stamen.
(a) Aestivation:The mode of arrangement of sepals or petals in floral bud with respect to the other members of the same whorl is known as aestivation.(b) Placentation:The arrangement of ovules within the ovary is known as placentation.(c) Actinomorphic:When a flower can be divided into two equal radial halves in any radial plane passing through the centre, it is said to be actinomorphic, e.g., mustard, datura, chilli, etc.,(d) Zygomorphic:When it can be divided into two similar halves only in one particular vertical plane, it is zygomorphic, e.g., pea, gulmohur, bean, Cassia, etc.(e) Superior ovary:A superior ovary is an ovary attached to the receptacle above the attachment of other floral parts.(f) Perigynous flower:If gynoecium is situated in the centre and other parts of the flower are located on the rim of the thalamus almost at the same level, it is called perigynous.(g) Epipetalous stamen:When stamens are attached to the petals, they are epipetalous, e.g. brinjal.