Q.62 With respect to adhesion and cohesion of stamens, identify the INCORRECT statements.
P. Adnation of stamens to petals is described as epiphyllous stamens
Q. In Calotropis, stamens and carpels are united to form gynostegium
R. In syngenesious stamens, filaments are united to form a bundle while the anthers are free
S. Synandrous stamens found in Cucurbita represent the union of filaments as well as anthers
(A) P, Q (B) P, R (C) Q, S (D) Q, R

P and R are the INCORRECT statements about stamen adhesion and cohesion.

Question Breakdown

This GATE Life Sciences question tests floral morphology terminology for stamen fusion (cohesion among stamens, adhesion to other floral parts). Identify false statements among standard botanical classifications.

Statement Analysis

P: Adnation of stamens to petals = epiphyllous stamens

INCORRECT. Epiphyllous = stamens fused to perianth (tepals in monocots like Lilium); epipetalous = petals in dicots.

Q: Calotropis stamens + carpels form gynostegium

CORRECT. In Asclepiadaceae, staminal column fuses stamens + gynoecium into gynostegium for pollinia pollination.

R: Syngenesious stamens = filaments united, anthers free

INCORRECT. Syngenesious (Asteraceae like sunflower) = anthers connate into cylinder, filaments free.

S: Synandrous stamens in Cucurbita = filaments + anthers united

CORRECT. Synandrous = complete fusion of both filaments and anthers (Cucurbitaceae).

Correct Choice

(B) P, R

Adhesion cohesion stamens incorrect statements clarified for GATE Life Sciences: epiphyllous vs epipetalous, syngenesious anther fusion.

Stamen Fusion Types

Cohesion (stamen-stamen):

• Monadelphous: Filaments fused (Hibiscus)

• Diadelphous: 2 bundles (Pea)

• Polyadelphous: Many bundles (Citrus)

• Syngenesious: Anthers fused, filaments free (Sunflower)

• Synandrous: Both fused (Cucurbita)

Adhesion (stamen-other parts):

• Epipetalous: Petals (Datura)

• Epiphyllous: Tepals (Aloe)

• Gynostegium: Stamens + carpels (Calotropis)

Truth Table

GATE Exam Relevance

Standard XL-Plant Morphology PYQ. Key distinctions: Epiphyllous (monocot tepals) ≠ epipetalous (dicot petals); syngenesious (anthers only) ≠ synandrous (both parts). Diagram practice essential.