Question

An intersexual flower has
A. No nonessential flower whorl
B. No essential floral whorl
C. Both the essential floral whorls
D. All the floral whorls

Answer 1

Hint: Flower is the reproductive structure of angiosperms. A normal flower has four different kinds of whorls arranged on the swollen end of the stalk, called thalamus. These are calyx, corolla, androecium and gynoecium.

Complete Answer:
- In some flowers, the calyx and corolla are fused and that part is known as perianth. Flowers having both androecium and gynoecium are called bisexual and those having any one of these parts are called unisexual.
- An androecium consists of stamens. Each stamen has a filament and an anther. Usually, each anther has 2 lobes and each lobe has two chambers, the pollen sacs, which produce pollen grains. A sterile stamen is called a staminode.
- A gynoecium represents the female reproductive organ of the flower. It is made up of one or more carpels. A carpel has a stigma, style and ovary. The basal enlarged part is the ovary, attached to it is an upright extension called style on which the stigma rests which is a pollen receptive surface. The ovary encloses ovules which are attached to the placenta.

Two types of pollination is present in flowers: Self-pollination and cross pollination.
- Self-pollination occurs when pollen from the anther falls on the stigma of the same flower, or another flower of the same plant. Cross pollination occurs when pollen from anther of a flower lands on the stigma of another flower of the same species.
- Self-pollination mostly occurs in bisexual or intersexual flower. An intersexual / bisexual flower is the one that has both the essential whorls.

Hence, the correct option is option C, ‘both the essential floral whorls’.

Note: The flowers consisting all the floral whorls are called a complete flower whereas an intersexual flower has both the essential ones i.e. the androecium and the gynoecium.