NO diffuses locally through tissues and activates an

intracellular NO receptor with guanylyl cyclase

activity in nearby smooth muscle cells

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#XL - R Botany

Special Inflorescence;

a. Cyathium

b. Hypanthodium

c. Coenanthium

Cyathium;

small unisexual flowers enclosed by a common involucre which mimics a single flower.

Male flowers = scorpioid manner and is represented only by stamens Female flower is solitary and centrally located on a long pedicel and is represented only by pistil

Ex- Pedilanthus

Hypanthodium

Receptacle is closed except a small opening called ostiole which is covered by a series of bracts. 

Example: Ficus sp. (Banyan and Pipal)

Coenanthium

Circular disc like fleshy open receptacle that bears pistillate flowers at the center and staminate flowers at the periphery.

Ex: Dorstenia

#Id: 10756

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The flower

Perfect flowers have both an androecium and a gynoecium

Imperfect flowers have one or the other and are termed pistillate if they contain female reproductive structures or staminate if only male reproductive structures

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Symmetry of flowers

actinomorphic (radial symmetry).

Example;  Mustard, datura, chilli.

(Brassicaceae, Solanaceae and Liliaceae family)

zygomorphic (bilateral symmetry).

Example;   pea, gulmohur, bean, Cassia.

(Fabaceae family)

#Id: 10758

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Flower is asymmetric (irregular)

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Parts of flowers

Sepals collectively form the calyx, 

The calyx may be gamosepalous  (sepals united) or polysepalous (sepals free)

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#XL - R Botany

The next internal whorl is the corolla and is composed of petals. corolla may be also united gamopetalous (petals united) or polypetalous (petals free).