Question

Syngenesious condition is found in the family
(a) Liliaceae
(b) Malvaceae
(c) Compositae
(d) Cruciferae

Answer 1

Hint: Syngenesious condition is found in the family of plants which is known mostly for its ornamental plants. A unique type of inflorescence is observed where the flower head is composed of many minute flowers with two different sets on the inner side and periphery.

Complete answer:
Syngenesious condition is an arrangement of stamens where their anthers are fused while their filaments are free. The fused anthers form a circle around the gynoecium. It is seen in the Compositae or Asteraceae family. E.g. Tagetes (Marigold), Helianthus (Sunflower).
Additional information:
Some characteristics of the Compositae family are:
- The members of this family are herbs or shrubs. They are rare trees. Based on habitat, they are usually xerophytic e.g.Proustia or hydrophytes like Cotula.
- The Taproot system is most prominent, though, in some fibrous root systems can be observed e.g. goldenrod(Solidago).
- The leaves can be alternate, opposite, and rarely whorled. Leaves are exstipulate i.e stipules are absent.
- The inflorescence is capitulum or racemose head. Here, the receptacle bears small sessile flowers which are called florets. The receptacle is formed by the flattening of the peduncle
- Florets on peduncles are arranged centripetally i.e younger ones near the center while older ones protrude on the periphery or outside. Two types of florets are present- ray florets and disc florets.
- The peripheral ray florets are sterile or female and zygomorphic while the central disc florets are bisexual and actinomorphic.
- A whorl of bracts called involucre is present on either side of the inflorescence.
Monadelphous or epipetalous condition is observed in the Malvaceae family. E.g Hibiscus. Six polyandrous stamens with a tetradynamous condition (four longer stamens are inner to two shorter ones) are observed in the Cruciferae family. E.g Brown mustard. Six stamens arranged in two trimerous whorls(3+3) with free filaments or epiphyllous(stamens fused with tepals) in the Liliaceae family. E.g Tulips.

So, the correct answer is ‘Compositae.’

Note: Some important terms to remember:
- Inflorescence: The manner in which the flowers are arranged as well as distributed over a plant is known as inflorescence. The arrangement occurs on a peduncle which is the axis of inflorescence.
- Actinomorphic: When flowers are radially symmetrical i.e two equal halves will be obtained from any plane of an axis passing through the center.
- Zygomorphic: When flowers are bilaterally symmetrical or they produce equal halves only from one plane of the axis.