Question

Select the correct statement/s.
I. Basal placentation is seen in pea plants.
II. A sterile stamen is called filament.
III. Long filamentous threads protruding at the end of young cob of maize are stigma.
IV. Keel is the characteristic feature of bean flower.
V. Synandrous flowers have fused stamens.

• A. II, V
• B. IV, V
• C. I, IV
• D. II, IV

Answer 1

The correct option is B IV, V

In marginal placentation the placenta forms a ridge along the ventral suture of the ovary and the ovules are borne on this ridge forming two rows, as in pea.
In basal placentation, the placenta develops at the base of ovary as in sunflower, marigold.

Sterile stamen lacks anther and cannot produce pollen. They are termed as staminode.

In cob of maize, each ovary has a long silky (hairy) style, called corn silk. The styles collectively protrude at the end of a young cob by exposing the stigma in air to receive pollen.

In vexillary aestivation the largest petal (standard) overlaps the two lateral petals (wings) which in turn overlaps the two smallest anterior petals (Keel). e.g. Bean flower

Synandrous flower: Stamens are fused along their entire length of filaments and anthers are fused. E.g. Bitter-gourd.