Class XII Practical: Taxonomy - Floral Characteristics, Diagram & Formula

Objective

To study the floral characteristics, construct the floral diagram, and write the floral formula for a representative plant from a given family.

Guidelines

1. Specimen Selection: Choose a fresh flower from one of the specified families (Malvaceae, Leguminosae – Papilionaceae, Solanaceae, Liliaceae/Amaryllidaceae, Cruciferae, Compositae, Gramineae).
2. External Morphology: Observe and note down external features:
   • Type of inflorescence.
   • Bracteate/Ebracteate, Bracteolate/Ebracteolate.
   • Pedicellate/Sessile.
   • Symmetry (Actinomorphic/Zygomorphic).
   • Sexuality (Unisexual/Bisexual).
3. Dissection & Counting: Carefully dissect the flower and count the number of parts in each whorl:
   • Calyx: Sepals (number, aestivation, fusion).
   • Corolla: Petals (number, aestivation, fusion).
   • Androecium: Stamens (number, arrangement, fusion, anther attachment).
   • Gynoecium: Carpels (number, fusion, ovary position, placentation).
4. Floral Diagram: Draw a floral diagram representing the arrangement of floral parts in concentric circles, their relative positions, and fusion.
5. Floral Formula: Write the floral formula using standard symbols to represent symmetry, sexuality, and the number and fusion of parts in each whorl.

Expected Outcome

Ability to systematically analyze a flower, represent its structure through a floral diagram, and summarize its characteristics using a floral formula.