Question

A monothecous stamen has
A) Small anther
B) Sterile anther
C) One lobed anther
D) One chambered anther

Answer 1

Hint: In a flower, the male reproductive organ is known as the stamen. A monothecous stamen is also known as one celled stamen.

Complete Answer:
- Each stamen consists of an anther, connective and filament. Anther can be dithecous or monothecous. A monothecous anther consisting of two sporangia or two locules. So it is known to be bisporangiate or bilocular. A dithecous anther comprises four sporangia or four locules. So it is known to be tetrasporangiate or tetralocular.

Now, let us find the solution from the options-
- The stamen is called monothecous or one celled stamen as it consists of a single lobe.
- They are named dithecous when the anthers have two-chambered, and they are called monothecous if they have a single-chambered.
- The anthers that include two lobes and four pollen sacs are dithecous or tetrasporangiate and the anther that has only one lobe and two pollen sacs are monothecous or bisporangiate.

Thus, the correct answer is option (C) and (D).

Note: Anther is the upper swollen portion of stamen generally having two theca or lobes in Malvaceae family has only a single lobe or theca. Two microsporangia found in each lobe. The dithecous has two lobed anthers. Anther of one lobe is called monothecous. Pollen grains, i.e. microspores are filled in theca. Pollen grains are male spores or male reproductive units.