Question

The shape of a sporangium in fern is
A. Biconvex
B. Circular
C. Biconcave
D. Plano-convex

Answer 1

Sporangium refers to the spore-containing capsule. They may be differently shaped. In ferns, the sporangium has both sides convex. Sporangium plays a vital role in asexual reproduction. In mosses, an unbranched sporophyte produces a single sporangium.

Complete answer:
The form of the sporangium is biconvex in a fern. There is a multicellular stalk and a biconvex capsule on each sporangium. Each sporangia in ferns is a spore-containing capsule. Typically, they form clusters called ‘sori’. A structure called an indusium cover Sori. Some ferns spread their sporangia along with decreased leaf segments or along the leaf-margin. For the identification of ferns, the location and arrangement of the sporangia are very important. There are fertile fronds which have sporangia on their underside, and others which are not sterile. An enclosure in which spores are produced is a sporangium. It can be multicellular or a single cell. Through mitosis, sporangia can develop asexual spores, but sporangia are the site of meiosis in almost all land plants and many fungi develop genetically specific haploid spores. Sporangia can be lateral or terminal of stems or associated with leaves.

So, the correct answer is option A.

Note: In the ferns, the sporangia are clustered into dense aggregations called ‘sori’ which appear as round dots on the underside of the fronds. Sporangia are sites of meiosis and produce genetically unique haploid spores. Oospores germinate by means of a germ tube that produces sporangium.