Question

In a monadelphous condition, stamens have
A. Filaments of all united in one group but anthers are free.
B. Filaments united in group and anthers are absent.
C. Anthers are fused but filaments are free.
D. Both anther and filaments are fused.

Answer 1

Hint: Monoadelphous condition is a condition formed in the stamen of the androecium, the male reproductive system in flowering plants. Monadelphous is a type of modification in the stamen.

Complete answer: Flowers have both reproductive and non-reproductive structures arranged in four whorls. These four include calyx, the corolla, the gynoecium and the androecium. The calyx is the outermost whorl made up of a green, leaf-like structure called sepals. The corolla is the whorl containing colourful petals. The gynoecium is an innermost whorl made up of female reproductive structures called carpels. The androecium is a whorl that contains male reproductive structures called stamens. The non-reproductive structures of flowers are the calyx and corolla and the androecium and gynoecium are the reproductive structures of the flowers. Gynoecium produces female reproductive egg cells and androecium produces pollen. The stamen can be modified by fusion. The fusion of stamens among one another or with other floral parts is known as the union of stamens. It is two types of cohesion of stamens or adhesion of stamens. The fusion of stamens with other parts of the flower is called the adhesion of stamens. The fusion of stamens among each other is called cohesion of stamens. Cohesion is of three types; adelphi, syngenesious and synandrous. In androecium, anthers are free, filaments are fused and forms into bundles is known as adelphi. Based on the number of bundles, it is of the following types;
Monadelphous: Here, filaments of all stamens are united to form only one bundle.
Diadelphous: Filaments of stamens are fused forming two bundles.
Polyadelphous: Stamen filaments are fused to form many bundles.
Hence, the correct answer is option A.

Note: Monadelphous stamen is seen in the Hibiscus flower, where filaments of stamen are fused into one bundle. Diadelphous e.g. is Dolichos, here it has 10 stamens out of which 9 filaments fuse together to form one bundle and the last one filament is left alone as a second bundle. An example of Polyadelphous is Citrus.