Write a floral formula
"Write a floral formula" is a free, interactive Class 11 Biology simulation for NEET, built on the NCERT section "Floral formula and Solanaceae" in Morphology of Flowering Plants. Set a flower's features and watch its floral diagram and formula write themselves: symmetry, sex, whorl counts, fusion brackets, adhesion lines and the superior/inferior bar on G. NEET has asked about this idea 2 times in 10 years of papers.
From the lesson Floral formula and Solanaceae in Morphology of Flowering Plants. Change the values and watch what happens.
What it shows
NCERT §5.8–5.9
Set a flower's features and watch its floral diagram and formula write themselves: symmetry, sex, whorl counts, fusion brackets, adhesion lines and the superior/inferior bar on G.
Controls
5 to try
- Segmentedsymmetry ⊕ / %
- SliderK, C, A, G counts 0–10
- Toggle per whorlfused (brackets)
- Togglestamens on petals (adhesion line)
- Segmentedovary superior / inferior
Try this
Produce the Solanaceae formula ⊕ ⚥ K(5) C(5) A5 G(2) with epipetalous stamens and a superior ovary, then the mustard formula.
Common mistake
The line under G means inferior ovary.
In NEET
10 years of papers
Asked 2 times in 10 years of NEET.
See the past questions: Morphology of Flowering Plants (chapter)
The idea behind it
NCERT §5.8, §5.9, Figures 5.16–5.17
- A semi-technical description is short, simple and scientific, and follows a fixed order: habit, then vegetative characters (root, stem, leaves), then floral characters (inflorescence, flower parts), then a floral diagram and a floral formula.
- Floral formula symbols: Br bracteate, K calyx, C corolla, P perianth, A androecium, G gynoecium, ⊕ actinomorphic, % zygomorphic, ⚥ bisexual, ♂ male, ♀ female. A line under G means a superior ovary; a line over G means an inferior ovary.
- Fusion within a whorl is shown by putting the number in brackets, e.g. C(5). Adhesion between whorls is shown by a line drawn over the symbols concerned, e.g. over C and A for epipetalous stamens.
- A floral diagram shows the number of parts, their arrangement and their relation to one another. A dot at the top marks the mother axis; calyx is the outermost ring and gynoecium the centre.
- The worked example (Figure 5.16) is mustard, family Brassicaceae: ⊕ ⚥ K2+2 C4 A2+4 G(2), ovary superior.
- Solanaceae, the potato family, is a large family spread through the tropics, subtropics and temperate zones. Example figured: Solanum nigrum (makoi).
- Vegetative: mostly herbs and shrubs, rarely small trees. Stem herbaceous (rarely woody); potato (Solanum tuberosum) has an underground stem. Leaves alternate and simple (rarely pinnately compound), without stipules (exstipulate), with reticulate venation.
- Floral: inflorescence solitary, axillary or cymose; flower bisexual and actinomorphic; five united, persistent sepals and five united petals, both valvate; five epipetalous stamens; bicarpellary, obliquely placed, syncarpous, superior, bilocular ovary with a swollen placenta bearing many ovules (axile). Fruit berry or capsule; seeds many, endospermous.
- Floral formula: ⊕ ⚥ K(5) C(5) A5 G(2), with a line joining C and A (epipetalous) and the ovary superior.
- Uses: tomato, brinjal and potato are foods; chilli is a spice; belladonna and ashwagandha are medicines; tobacco is fumigatory; petunia is an ornamental.
Questions
4 answers
- What does the "Write a floral formula" simulation show?
- Set a flower's features and watch its floral diagram and formula write themselves: symmetry, sex, whorl counts, fusion brackets, adhesion lines and the superior/inferior bar on G.
- What mistake does the "Write a floral formula" simulation fix?
- A common mistake it clears up: the line under G means inferior ovary.
- Has NEET asked about this idea?
- Yes. NEET has asked about this idea 2 times in 10 years of papers.
- Is this simulation free?
- Yes. It is free and runs in the browser on a phone or a laptop. It belongs to the lesson "Floral formula and Solanaceae" in Morphology of Flowering Plants (Class 11 Biology).
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