Biology · Morphology of Flowering Plants · NEET
The floral formula is Br ⊕ ⚥ P(3+3) A3+3 G(3̄). Read it part by part: Br = bracteate; ⊕ = actinomorphic (radial symmetry); ⚥ = bisexual; P(3+3) = perianth of 6 tepals in two whorls, the brackets meaning they are often united (gamophyllous); A3+3 = androecium of 6 stamens in two whorls; G(3̄) = gynoecium of 3 united carpels with a line ABOVE the 3 meaning the ovary is superior. For NEET, memorise the '3s' pattern — it separates Liliaceae from the pentamerous (5s) Solanaceae.
In many monocots like the lily, the sepals and petals look exactly alike — same colour and same shape. When the two outer whorls cannot be told apart, we do not call them calyx and corolla separately. Instead we group all six into one term, the perianth, and each unit is called a tepal. That is why the formula uses P(3+3) and not K3 C3. NEET often tests this: a family using 'P' in its formula (Liliaceae) is a strong clue it is a monocot family.
The ovary is SUPERIOR. In the floral formula G(3̄), the small line (bar) placed ABOVE the G shows a superior ovary, which means the flower is hypogynous — the other whorls sit below the ovary. A bar UNDER the G would mean inferior. Students confuse this with the sunflower family (Asteraceae) which has an inferior ovary; Liliaceae is superior. Remember: bar on TOP = ovary on top = superior.
There are 6 stamens, arranged in two whorls of 3 (A3+3). They are EPIPHYLLOUS (also written epitepalous), meaning they are attached to the perianth/tepals. This is different from Solanaceae, where the 5 stamens are EPIPETALOUS (attached to the petals). The word changes because Liliaceae has tepals (perianth), not distinct petals. NEET 2024 matched 'Epiphyllous' with 'Lily' for exactly this reason.
Both flowers are actinomorphic and bisexual, but the numbers differ. Liliaceae is trimerous (3s): P(3+3) A3+3 G(3̄) — 6 tepals, 6 stamens, 3 carpels, superior ovary. Solanaceae is pentamerous (5s): K(5) C(5) A5 G(2) — 5 sepals, 5 petals, 5 epipetalous stamens, 2 carpels. Key tells: Liliaceae uses P (perianth) and is tricarpellary; Solanaceae uses separate K and C and is bicarpellary with an obliquely placed septum.
Common NEET examples are Allium cepa (onion), Allium sativum (garlic), Aloe, Lilium (lily), Asparagus, Colchicum autumnale and Gloriosa. Many are medicinal or ornamental. Allium (onion/garlic) and Aloe appear most often in NEET matching and 'odd one out' questions, so link the plant name to the '3s' formula.
Tricarpellary, syncarpous gynoecium is found in flowers of:
Match the floral formulae in List I with the families in List II. List I: (a) % ⚥ K(5) C1+2+(2) A(9)+1 G1 (b) ⊕ ⚥ K(5) C(5) A5 G(2) (c) ⊕ ⚥ P(3+3) A(3+3) G(3) (d) ⊕ ⚥ K2+2 C4 A2+4 G(2). List II: (i) Brassicaceae (ii) Liliaceae (iii) Fabaceae (iv) Solanaceae.
Match List I (Types of Stamens) with List II (Example). A. Monadelphous, B. Diadelphous, C. Polyadelphous, D. Epiphyllous. I. Citrus, II. Pea, III. Lily, IV. China-rose.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Liliaceae is a monocot family. Clues in its floral formula are the trimerous plan (parts in 3s), the perianth (P) of tepals instead of separate calyx and corolla, and axile placentation with a tricarpellary ovary.
Axile placentation. The ovary is trilocular (three chambers) and the ovules are attached to a central axis where the septa meet — this is axile placentation, the same type seen in Solanaceae and China rose.
The bracket shows the tepals are united (fused/gamophyllous). P(3+3) means a perianth of two whorls of three tepals each that are joined together; without brackets they would be free.
Colchicum autumnale belongs to Liliaceae, so it does NOT show vexillary aestivation or diadelphous stamens (those are Fabaceae features). NEET uses it as a distractor beside Pisum sativum. Tag Colchicum, Allium and Aloe firmly to the Liliaceae '3s' plan.
The perianth of Liliaceae usually shows valvate aestivation, where the tepals of a whorl meet edge to edge without overlapping.
