Flower Parts
Transcription
Flower Parts
Flower Parts Receptacle The receptacle is the apex of the flower stalk (peduncle or pedicel) where some or all of the floral organs are inserted. It is also referred to as the torus. It is usually a small transition area, but can be enlarged or swollen into a distinct organ. Stigma Stamens Petals Ovary Style Sepals Ovary Receptacle Receptacle Back to main flower menu Peduncle Next Peduncle Lily (Lilium) with front petals removed. Back to flower parts menu Main menu Flower Parts Receptacle - Disk When the receptacle forms an enlarged structure above the peduncle or pedicel, it is termed a receptacle disk (disc) or gynobase. The disk commonly contains the petals and stamens inserted on the disk and the ovary is either on top (hypogynous), surrounded (perigynous) or covered (epigynous) by the disk. Trumpet vine (Campsis) in bud Petals Stamens Ovary Receptacle disk Peduncle Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Receptacle – Hypogynous disk A receptacle disk is considered hypogynous if the ovary sits on top of the disk and the petals and stamens arise from the disk. Stamens Stigma Stigma Cape primrose Style (Streptocarpus) section with petals and stamens removed Petals Ovary Style Ovary Sepals Receptacle Back to main flower menu Receptacle disk Sepals Peduncle Back Next Back to flower parts menu Main menu Flower Parts Receptacle – Perigynous disk (hypanthium) The disk is considered perigynous when it surrounds the ovary, but the sepals, petals and stamens arise from the receptacle. This type of receptacle cup is also called the hypanthium. Stamens Petals Sepals Ovary Receptacle disk (hypanthium) Perigynous receptacle disk Back to main flower menu Back Next Flower in the bud Open flower Balloonflower (Platycodon) Back to flower parts menu Main menu Flower Parts Receptacle – Epigynous disk The receptacle disk is epigynous when it covers (adheres) the ovary and the other floral organs arise from the disk. Stamens Intact flower. Style and stigma Style and stigma Section of flower through the disk with petals and two stamens removed. Style and stigma Petals Stamens Receptacle disk covering ovary Sepals Petals Epigynous receptacle disk Back to main flower menu Back Receptacle disk Ovaries Spindle tree (Euonymus) Next Back to flower parts menu Main menu Flower Parts Receptacle – Epigynous disk The ginseng family (Araliaceae) have prominent, epigynous receptacle disks from the pedicel. The stamens arise from the disk that also covers the style. Inflorescence Single flower Stamen Stigma Receptacle disk covered with nectar Petal English ivy (Hedera) Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Receptacle- Disk Black gum (Nyssa) produces separate male and female flowers. The male flowers are an example of a receptacle disk in a flower without an ovary. Black gum (Nyssa) male flowers The receptacle disk becomes more obvious as the petals and stamens abscise. Receptacle disk Stamens Receptacle disk Pedicel Petals Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Receptacle – Nectar disk In many species, the receptacle disk produces nectar and is termed a nectar disk. The nectar disk (ring) often surrounds the base of the ovary. Stigma Vertical section of the flower with part of the petal tube and receptacle removed. Stamens Nectar disk Style Flower with petals and stamens, style and stigma removed. Cut style Receptacle tissue Petals Back to main flower menu Sweet potato vine (Ipomoea) Back Next Nectar disk Back to flower parts menu Ovary Main menu Flower Parts Receptacle – Nectar gland Members of the mint family (Lamiaceae), have a well developed receptacle disk and a gynobastic style. Nectar gland A gynobastic style is attached to the receptacle disk and ovary side rather than the ovary apex. Style Nectar gland Ovaries In Salvia, the nectar gland also arises from the receptacle disk. Receptacle disk Front petals and stamens removed. Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Receptacle – Expanded or elongated In flowers that contain many pistils, the receptacle is enlarged or elongated to accommodate their number. Section through the flower bud Pistils Pistils Petals Style Stamens Enlarged, flattened receptacle Back to main flower menu Dorstenia Back Next Elongated receptacle Back to flower parts menu Magnolia Main menu Flower Parts Receptacle – Expanded or elongated Lotus (Nelumbo) produces a large expanded disk that forms primarily above the stamen whorl and completely surrounds the ovaries. Receptacle disk Receptacle disk Stigma Stamens Enclosed ovary Petals Stamens Lotus (Nelumbo) Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Receptacle - – Expanded or elongated Petals Rose has a perigynous flower with many independent, simple pistils. Sepals Note how the sepal, petals, and stamens attach at the rim of the hypanthium and the ovaries are inserted down into the cup formed by the hypanthium. Back to main flower menu Many simple pistils Pistils Stamens Rim of hypanthium Back Next Hypanthium Ovaries Ovaries Back to flower parts menu Main menu Flower Parts Receptacle - Gynophore A gynophore is an extension of the receptacle (stalk) that raises the pistil above the petal whorl. In caper (Capparis), the receptacle extension raises the pistil above the petals and stamens. Gynophore Petals Pistil Pistil Stamens Gynophore Receptacle Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Receptacle - Gynophore In Cleome spinosa, the gynophore continues to elongate pushing the fruit away from the main flowering axis. Gynophore Pistil Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Receptacle - Gynophore Passionflower (Passiflora) When the stamens and pistil are raised above the petals, the gynophore (receptacle stalk) is further differentiated as an androgynophore. Ovary Stamens Androgynophore Corona Petals Back to main flower menu Back Stigma and styles Next Sepals Back to flower parts menu Petals Main menu Flower Parts Receptacle – Stylar column In crane’s-bill, there is an elongated receptacle surrounded by equally long styles (stylar column). As the fruit matures, the styles coils to lift each fruitlet above the stylar column. The spring-like action discharges a single seed from each fruitlet. Crane’s bill (Geranium) Fruitlets Styles Receptacle Elongated styles Receptacle (stylar) column Ovaries Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Receptacle In the composite family (Asteraceae), the inflorescence is called a capitulum or head. It contains many stalkless (sessile) flowers inserted into the receptacle disk. This is similar to the receptacle in single flowers with many pistils. Many individual flowers on the receptacle. Disk florets Ray floret Bracts Peduncle Back to main flower menu Receptacle disk Back Next Ray floret Receptacle disk Zinnia Back to flower parts menu Disk floret Bracts Peduncle Main menu Flower Parts Receptacle – Edible receptacles The receptacle in strawberry (Fragaria) is elongated and similar to the receptacle seen in the composites. The difference is that rather than many sessile florets, strawberry has numerous independent pistils inserted on the conical receptacle. Stamens Stamens Pistils Petals Sepals Pistils on the receptacle Petals Fragaria x ‘Lipstick’ Back to main flower menu Back Next Receptacle Back to flower parts menu Ovary Main menu Flower Parts Receptacle – Edible receptacles The receptacle in strawberry continues to expand and becomes the edible “fruit”. Flowers Receptacle Sepals Sepals Receptacle Achenes Strawberry (Fragaria) Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Receptacle – Edible receptacles In apple, the fruit is a pome where the inner fruit and seeds (inside the papery endocarp) is surrounded by modified floral receptacle tube (hypanthium) that grows to cover the botanical fruit. It is also found in pear and quince. Receptacle Seeds Carpel tissue Remnant flower tissue Back to main flower menu Apple (Malus ) Back Next Back to flower parts menu Main menu Flower Parts Receptacle – Edible receptacles In figs (Ficus) the flower is termed a hypanthodium where the flowers are formed on the surface of an expanded receptacle that is folded to enclose the flowers. Ostiole Ostiole Flowers Receptacle Back to main flower menu Back Receptacle Next Back to flower parts menu Fig (Ficus) The ostiole is a small opening in the receptacle that allows pollinating wasps to enter the flower. Main menu Flower Parts Receptacle – Edible receptacles Figs produce a syconium fruit, where the seeds are attached to an inverted receptacle. Inflorescence Compound fruit Single fruit Bracts Ostiole Back to main flower menu Back Fig (Ficus) Next Back to flower parts menu Receptacle Main menu Flower Parts Receptacle – Edible receptacles In cashew (Anacardium occidentale), the receptacle swells to become the colorful portion of the fruit. It is technically called a hypocarpium. The fleshy receptacle is edible and referred to as a cashew apple. Receptacle (Cashew apple) Below the swollen receptacle is the true fruit – a drupe. The culinary cashew nut is actually the seed located inside the drupe. Drupe Back to main flower menu Back Back to flower parts menu Main menu