Question

To study floral whorls of different flowers collected from a garden project

Answer 1

Answer:

The following points highlight the four essential accessory whorls of a flower. The essential accessory whorls are:-

1. Calyx

2. Corolla

3. Androecium

4. Gynoecium.

Explanation:

Accessory Whorls # 1. Calyx:

The calyx is the outermost accessory set of floral leaves, consisting of sepals. Sepals are usually green inconspicuous bodies. They protect the essential whorls against mechanical injuries and desiccation in the bud stage.

So, their function is mainly protective. Sepals of some plants become coloured like the petals and are called petaloid, e.g. Caesalpinea (B. Krishnachura). In Mussaenda one of the sepals is transformed into a flat leaf-like structure (Fig. 88). In the sunflower family the sepals are modified into hairy bodies called pappus which help in the dispersal of fruits.

Flower of Mussaenda

If the sepals are free the calyx is called polysepalous, and they are united the calyx is gamosepalous. The gamosepalous calyx is more or less like a tube in which the num­ber of sepals may be easily deter­mined by count­ing the teeth or lobes. In many cases sepals fall off before the flowers fully open out. They are called caducous sepals, e.g. Poppy; while in others they fall off with other parts after fertilisation.

These are deciduous sepals. In some flowers sepals persist even up to the fruit stage and are called persistent, e.g. brinjal, tomato. Sometimes they not only persist but grow to form a part of the fruit, as in Dillenia (B. Chalte), Physalis (B. Tepari). These are called accrescent sepals.

Accessory Whorls # 2. Corolla:

It is the second accessory whorl of the flower, the individual parts of which are called petals. They make the flowers showy and attractive, as the petals are brightly coloured and often sweetly scented.

The function of corolla is twofold