Tag: basics of leaf and flower

Adhesion in a flower occurs when the dissimilar floral parts unite with each other. For example, stamens can unite with petals to form epipetalous flowers, stamens can unite with perianth lobes to form epiphyllous flowers, stigma, style and stamens can unite to form gynostegium etc.

Flower with both the sex organs is called an intersexual, bisexual, hermaphrodite or perfect flower.

The flowers of Bougainvillea appear bright pink due to their bracts. This is called homochlamydeous condition when the calyx and corolla cannot be differentiated. These coloured bracts are called petaloid bracts.

A flower is characterised by the calyx and corolla as the non-essential whorls because these are not directly involved in the formation of gametes and fertilization. When these are absent, the flower is called achlamydeous. For example, flowers of willow.

An intersexual flower is also called as the perfect, bisexual or hermaphrodite flower. It has presence of both the male reproductive whorl called the androecium and the female reproductive whorl called the gynoecium. The units of androecium are called the stamens. The units of gynoecium are called the carpels. These are called essential whorls as they form the male gametes and female gametes. Hence, the correct answer is 'Both the essential floral whorls'

Trimerous flowers have flower parts, such as petals, sepals, and stamens, in sets of three. Pentamerous divided into five parts; specifically, having each floral whorl consist of five (or a multiple of five) members. A dicot is a type of flowering plant characterized by its two cotyledons, tetramerous or pentamerous flowers, and net-like leaf veins.  In monocots, flowers are trimerous (number of flower parts in a whorl in threes).

In plants like Beta vulgaris, the gynodioecious condition is seen in which some plants have bisexual or hermaphroditic or perfect flowers. These flowers have both the male sex organs (androecium) and female sex organs (gynoecium). Then there are some plants that have only the pistillate or female flowers. A population of plants belonging to a species in which there is a co-existence of bisexual and pistillate flowers is called gynodioecious.

A trioecious condition is defined as the presence of the male flowers (staminate flowers), the female flowers (pistillate flowers) and the hermaphroditic flowers in three different plants. For example, Mango.

The main function of leaf is photosynthesis. It produces food for the plant. It has a photosynthetic pigment chlorophyll which converts solar energy into chemical energy. The leaf is also involved in the transpiration process. The transpiration process helps in cooling of plant. The exchanges of gases takes place through stomata present on the leaves.