How many ways can you cut a flower in half?
"How many ways can you cut a flower in half?" is a free, interactive Class 11 Biology simulation for NEET, built on the NCERT section "Flower whorls and symmetry" in Morphology of Flowering Plants. Rotate a cutting plane through a flower viewed from above and count how many planes give mirror halves: many (actinomorphic), exactly one (zygomorphic) or none (asymmetric) NEET has asked about this idea 4 times in 10 years of papers.
From the lesson Flower whorls and symmetry in Morphology of Flowering Plants. Change the values and watch what happens.
What it shows
NCERT §5.5.1
Rotate a cutting plane through a flower viewed from above and count how many planes give mirror halves: many (actinomorphic), exactly one (zygomorphic) or none (asymmetric)
Controls
3 to try
- Dragrotate cutting plane 0–180°
- Segmentedmustard / datura / pea / Cassia / canna
- Toggleshow matching halves overlay
Try this
Find every symmetry plane of the pea flower and of mustard, and show canna has none.
Common mistake
Pea and gulmohur are actinomorphic.
In NEET
10 years of papers
Asked 4 times in 10 years of NEET.
See the past questions: Morphology of Flowering Plants (chapter)
The idea behind it
NCERT §5.5, §5.5.1, Figure 5.10
- The flower is the reproductive unit of angiosperms and serves sexual reproduction.
- A typical flower has four whorls, one above another, on the swollen tip of the pedicel called the thalamus or receptacle: calyx, corolla, androecium and gynoecium.
- Calyx and corolla are accessory organs; androecium and gynoecium are the reproductive organs.
- When calyx and corolla cannot be told apart, as in lily, together they are called the perianth.
- Bisexual flower: has both androecium and gynoecium. Unisexual flower: has only stamens or only carpels.
- Actinomorphic (radial symmetry): any radial plane through the centre cuts it into two equal halves. Examples: mustard, datura, chilli.
- Zygomorphic (bilateral symmetry): only one particular vertical plane gives two similar halves. Examples: pea, gulmohur, bean, Cassia.
- Asymmetric (irregular): no vertical plane through the centre gives two similar halves. Example: canna.
- Trimerous, tetramerous and pentamerous flowers have floral appendages in multiples of 3, 4 and 5.
- A bract is a reduced leaf at the base of the pedicel. Flowers with bracts are bracteate; flowers without them are ebracteate.
Questions
4 answers
- What does the "How many ways can you cut a flower in half?" simulation show?
- Rotate a cutting plane through a flower viewed from above and count how many planes give mirror halves: many (actinomorphic), exactly one (zygomorphic) or none (asymmetric)
- What mistake does the "How many ways can you cut a flower in half?" simulation fix?
- A common mistake it clears up: pea and gulmohur are actinomorphic.
- Has NEET asked about this idea?
- Yes. NEET has asked about this idea 4 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 "Flower whorls and symmetry" in Morphology of Flowering Plants (Class 11 Biology).
Embed this simulation
Free, with a link back
Teaching this idea? Put the simulation on your own page or LMS with this code.