Скачать или смотреть 🌻 Sunflower Family (Asteraceae) Composite of 🟡 & 🔆

🌻 Sunflower Family (Asteraceae) is Composite of 🟡 & 🔆 - In plants of Asteraceae, what appears to be a single 'daisy'-type flower is actually a composite of several much smaller flowers known as Capitulum or Head. By visually presenting as a single flower, capitulum functions in attracting pollinators, in same manner that other 'showy' flowering plants in numerous other, older, plant families have evolved to attract pollinators. Previous name for family 'Compositae' reflects fact that what appears to be a single floral entity is in fact a composite of much smaller flowers.

'Petals' or 'sunrays' 🔆 in an 'asteraceous' head are in fact individual strap-shaped flowers called Ray flowers or ray florets & 'sun disk' 🟡 is made up of smaller, radially symmetric, individual flowers called disc flowers or disc florets.

Word aster means 'star' in Greek, referring to appearance of most family members as a 'celestial body with rays'.

Capitulum, which often appears to be a single flower, is often referred to as a head. In some species, entire head is able to pivot its floral stem in course of day to track sun (like a 'smart' solar panel), thus maximizing reflectivity of entire floral unit & further attracting flying pollinators.

Nearest to flower stem lie a series of small, usually green, scale-like bracts. These are known as Phyllaries; collectively, they form Involucre, which serves to protect immature head of florets during its development.

Individual florets are arranged atop a dome-like structure called Receptacle.

Individual florets in a head consist, developmentally, of five fused petals (rarely four); instead of sepals, they have threadlike, hairy, or bristly structures, known collectively as a Pappus, (plural pappi). Pappus surrounds ovary & can, when mature & attached to a seed, adhere to animal fur or be carried by air currents, aiding in seed dispersal. Whitish, fluffy head of a dandelion, commonly blown on by children, consists of numerous seeds resting on receptacle, each seed attached to its pappus. Pappi provide a parachute-like structure to help seed travel from its point of origin to a more hospitable site.

A ray flower is a two- or three-lobed, strap-shaped, individual flower, found in head of most members of Asteraceae. Corolla of ray flower may have two tiny, vestigial teeth, opposite to three-lobed strap, or tongue, indicating its evolution by fusion from an ancestral, five-part corolla. In some species, 3:2 arrangement is reversed, with two lobes & zero or three tiny teeth visible opposite tongue.

A ligulate flower is a five-lobed, strap-shaped, individual flower found in heads of certain other asteraceous species. A ligule is strap-shaped tongue of corolla of either a ray flower or of a ligulate flower.

A disk flower (or disc flower) is a radially symmetric individual flower in head, which is ringed by ray flowers when both are present.

In some species, ray flowers may be arranged around the disc in irregular symmetry, or with a weakly bilaterally symmetric arrangement.
---
▪︎ (Heliopsis helianthoides) False Sunflower
---
▪︎ Genus Helianthus • 66 - Sunflowers
▪︎ Genus Heliopsis
Basic Latin
○ Heli for Sun
○ Anth for Flower (Ant 🐜 +🐘 = 🌼)
○ Ops for Face or Appearance
≈ Sun + Flower = Sunflower
≈ Sunflower like Appearance - Heliopsis
---
¹Helipiosis ²Helianthus
○ Rays - ¹pistillate ²neutral
○ Receptacle ¹conical ²flat or conavex
○ Claff ¹linear-lanceolate ²broad, embracing achenia
○ Pappus ¹none ²two or four deciduous scales.
---
▪︎ (Rudbeckia subtomentosa) Sweet Coneflower
▪︎ (Helianthus mollis) Ashy Sunflower
▪︎ (Ratibida pinnata) Grayhead or Pinnate Prairie Coneflower
▪︎ (Eupatorium serotinum) Late Boneset, Late Thoroughwort
▪︎ (Rudbeckia fulgida) Orange Coneflower, Perennial Coneflower
▪︎ (Eutrochium maculatum) Spotted Joe-Pyeweed
▪︎ (Eutrochium dubium) Coastal Plain Joe Pyeweed
▪︎ (Eutrochium purpureum), Purple Joe-Pyeweed, Sweetscented Joe-Pyeweed
▪︎ (Silphium perfoliatum) Cup Plant
▪︎ (Solidago canadensis) Canada Goldenrod, Canadian Goldenrod
▪︎ (Euthamia scabra)
▪︎ (Silphium terebinthinaceum) Prairie Dock, Prairie Rosinweed
▪︎ (Verbesina alternifolia) Wingstem, Yellow Ironweed
---
🇮🇳💎¹⁵²³
---