Problem 127 - Objective Biology for NEET

Question

Floral formula of solanaceae is(c) \(\oplus ? \mathrm{~K}_{(5)} \widehat{\mathrm{C}_{(5)} \mathrm{A}_{(5)}} \mathrm{G}_{(2)}\) (d) \(\oplus \delta \mathrm{K}_{(5)} \widehat{\mathrm{C}_{(5)} \mathrm{A}_{(5)}} \mathrm{G}_{(2)}\)

Step-by-Step Solution

Answer

The floral formula for Solanaceae matches option (c): '+ K(5) C(5) A(5) G(2)'.

Step 1: Understand the Symbols in Botanical Nomenclature

In botanical nomenclature, a '+' is used to denote a flower that is bisexual (having both stamens and carpels), and 'δ' represents a flower that is unisexual.

Step 2: Evaluate Option (c)

In this option, '+' is followed by K(5) C(5) A(5) G(2). This suggests that the flower is bisexual with 5 sepals (K), 5 petals (C), 5 stamens (A) and a gynoecium of 2 fused carpels (G). Given that Solanaceae typically have bisexual flowers, this formula aligns with what we know about their flower structure.

Step 3: Evaluate Option (d)

In option (d), 'δ' is followed by K(5) C(5) A(5) G(2). This implies that the flower is unisexual, which does not align with the standard flower structure for Solanaceae.

Key Concepts

Botanical Nomenclature

Understanding the language of plants is fundamental in botany. Botanical nomenclature is a formal system for naming plant species and describing their characteristics in a standardized way. It is a language that transcends geographical and linguistic barriers, allowing scientists from different parts of the world to communicate effectively about plant species.

Each component of a plant's structure has a corresponding symbol or abbreviation in the botanical nomenclature. For instance, 'K' stands for 'calyx' (the sepals of a flower), 'C' for 'corolla' (the petals), 'A' for 'androecium' (the stamens), and 'G' for 'gynoecium' (the female reproductive part). These symbols are used in a floral formula, a concise way to represent the structure of a flower.

In the case of the exercise provided, the floral formula for Solanaceae hints at a specific flower structure with 'K(5)' indicating 5 sepals, 'C(5)' indicating 5 petals, 'A(5)' indicating 5 stamens, and 'G(2)' suggesting 2 fused carpels. The prefix '+' suggests the presence of both stamens and carpels, defining the flower as bisexual.

Bisexual Flowers

Bisexuality in flowers refers to the presence of both male (androecium) and female (gynoecium) reproductive organs in the same flower. This is a common trait among many flowering plants and is significant in plant reproduction as it allows for self-fertilization, although cross-pollination is often preferred as it increases genetic diversity.

Within the family Solanaceae, which includes economically important plants like tomatoes, potatoes, and eggplants, bisexual flowers are a characteristic feature. The floral formula provided in the exercise, with the '+' symbol, is identifying the bisexual nature of Solanaceae flowers. It implies that these flowers contain both stamens (A) and pistils (G), making them capable of both producing pollen and receiving it for fertilization.

The correct identification of bisexual flowers is not only important for botanists but also for students preparing for competitive exams like NEET, where understanding flower structures can be a part of the botany section.

Botany for NEET

NEET (National Eligibility cum Entrance Test) is a significant pre-medical examination in India that tests knowledge in various science subjects, including botany. For students preparing for NEET, a strong grasp of botanical concepts such as plant anatomy, physiology, and taxonomy is crucial.

The study of plant families such as Solanaceae forms a part of the botany syllabus for NEET, where students must learn specific details about plant structures and functions. As seen in the exercise, learning how to interpret the floral formula is an essential skill. A correct interpretation can aid in identifying plant families and understanding their reproductive strategies. This is particularly important in the context of Solanaceae, given their economic and medicinal significance.

For NEET aspirants, mastering the use of botanical nomenclature and being able to decode floral formulas can contribute to a thorough understanding of botany topics, which can ultimately help them score better in the examination.