Skip to content
Login Register

#tepals

3 public questions tagged with this topic.

Plant Classification

When sepals and petals are indistinguishable, they are called

When perianth segments are indistinguishable in colour, texture and shape, each segment termed tepal to avoid mischaracterization as sepal or petal; collectively they form perigonium or perigone. Perianth remains general term for outer whorls ensemble, perigone sometimes used synonymously but strictly means true perigonium in lilioid monocots. Bracteoles are small bracts borne on pedicel, not perianth parts. Tepals occur prominently in Liliaceae, Palmae, Amaryllidaceae usually six arranged in two whorls 3+3 with petaloid colouration and valvate aestivation. Tepal terminology emphasizes homochlamydeous condition considered primitive within monocotyledons.

Ref: NCERT Class 11, Tepal terminology Liliaceae; Simpson, Plant Systematics, perigonium monocots

View Details
Plant Classification

Perianth with tepals is characteristic of

Liliaceae exhibits homochlamydeous perianth where calyx and corolla are not distinguishable morphologically, segments called tepals, typically petaloid, six arranged in two trimerous whorls 3+3 forming perigonium, polyphyllous or slightly gamophyllous with valvate aestivation. This condition reflects monocot ancestry where differentiation into sepals and petals secondarily reduced. Fabaceae shows clear papilionaceous C with standard wings keel, Solanaceae gamosepalous and gamopetalous K(5) C(5), Brassicaceae 4 sepals and 4 petals. Presence of conspicuous coloured tepals hence diagnostically identifies lily, tulip, Gloriosa and Allium as lilioid monocots.

Ref: NCERT Class 11 Biology Chapter 5: Liliaceae perianth tepals; Simpson, Plant Systematics, Lilioid monocots

View Details
Plant Classification

Tepals are characteristic of flowers where

Perianth segments termed tepals when calyx corolla differentiation absent, showing similar pigmentation, size and texture throughout, often both petaloid or sepaloid without clear distinction. Condition common in monocots Liliaceae where outer whorl not green sepaloid but showy, termed petaloid tepals, or in basal angiosperms like tulip, Magnolia where gradual transition from bracts to perianth evident morphologically. Sepals and petals indistinct genetically due to overlapping B-class MADS-box gene expression domain expansion. Presence only petals still corolla, only sepals calyx, absence achlamydeous, whereas tepal concept indicates undifferentiated perianth evolutionarily intermediate.

Ref: NCERT Class 11 Biology, Chapter 5: Perianth differentiation tepals monocot characteristic

View Details