Q.50 Find the odd one out
(A) Petal (B) Sepal (C) Petiole (D) Tepal
Correct Answer: (C) Petiole
Petiole is the odd one out as it represents the leaf stalk connecting blade to stem, while petal, sepal, and tepal are all floral organs in the flower perianth (outer whorls).
Option Analysis
(A) Petal: Modified leaf in corolla (inner perianth whorl); brightly colored to attract pollinators. Shares floral identity with sepal and tepal.
(B) Sepal: Modified leaf in calyx (outer perianth whorl); typically green, protects bud. Floral organ like petal and tepal.
(C) Petiole: Stalk of a leaf blade; supports photosynthesis, not reproduction. Lacks floral function, making it structurally and functionally distinct.
(D) Tepal: Undifferentiated perianth segment where sepal and petal are similar (e.g., lilies); serves both protective and attractive roles. Floral like petal/sepal.
In flower anatomy, the odd one out among petal, sepal, petiole, and tepal is petiole, as it functions as the leaf stalk while petal, sepal, and tepal comprise the reproductive perianth.
Floral Parts Defined
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Petal: Corolla segments; colorful, pollinator attractants.
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Sepal: Calyx segments; protective, often green.
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Tepal: Perianth parts in undifferentiated flowers (e.g., tulips, lilies).
Petiole Distinction
Petiole attaches leaf lamina to stem, handling water/nutrient transport. Absent from flowers, unlike the other three vegetative-to-floral modified leaves.
Exam Tip
Questions test perianth (petal/sepal/tepal) vs. vegetative (petiole) differentiation in angiosperm morphology.
