Question

In Cyathium inflorescence
A. Single male flower is surrounded by a female flower
B. Male and female flowers are borne in different planes
C. There is only one male and female flower
D. Single female flower is surrounded by many peripheral male flowers

Answer 1

Cyathium inflorescence consists of a small cuplike structure enclosing a female flower and several male flowers. In this, the female flower is centrally placed and numerous s male flowers are centrifugally arranged. It is characteristic of plants in the genus Euphorbia, for example- poinsettia.

Complete answer:
A cyathium is one of the specialized pseudanthia meaning false flowers. It forms the inflorescence of plants in the genus Euphorbia (Euphorbiaceae). A cyathium consists of:
- Five or rarely four bracteoles. These are small and united bracts. They form a cup-like involucre. Their upper tips are free and in the advent cover the opening of the involucre (like the shutter of a camera).
- Five (1 to 10) nectar glands, which are occasionally fused.
- The extremely reduced female flower stands in the center at the base of the involucre. It consists of an ovary on a short stem with the pistil.
- It is surrounded by five groups. One group at the base of each bracteole of extremely reduced male flowers. Each of them consists of a single anther on a stem.

Option A- single male flower is surrounded by a female flower
Cyathium inflorescence consists of a single female flower surrounded by male flowers.

Option B- Male and female flowers are borne in different planes
This is not true for Cyathium inflorescence.

Option C- There are only one male and female flower
Cyathium inflorescence consists of several male flowers.

Option D- Single female flower is surrounded by many peripheral male flowers
Cyathium inflorescence makes a cuplike structure of a Single female flower surrounded by many peripheral male flowers.

Hence, the correct answer is option (D).

Note: Inflorescences refers to complex structures with many functions. At anthesis they illustrate the flowers in ways that allow for the transfer of pollen. They also take part in the optimization of the plant's reproductive success. They provide nutrients to the developing flowers and fruits during flower and fruit development.