Question
Question: Sex organs in Funaria develop A. In protonema B. Outside capsule C. At the tip of leaf D. At...
Sex organs in Funaria develop
A. In protonema
B. Outside capsule
C. At the tip of leaf
D. At the tip of gametophore
Solution
The genus Funaria consists of 210 species of moss. They are found on shady and damp soil. Funaria hygrometrica is called “cord moss” because of the twisted seta which is very hygroscopic and untwists when moist. Funaria is monoecious in that males the male and female sex organs are on the same plant. However, they are specifically located on different shoots.
Complete answer:
The alternation of generation from free-living haploid gametophyte to semi parasitic diploid sporophyte occurs during the life cycle of Funaria.
In protonema: Incorrect Answer
A protonema is a thread-like chain of cells that forms the haploid phase in the life cycle of Funaria. This protonema that initially grows from the spore later develops into a leafy gametophore.
Outside capsule: Incorrect answer
The capsule is located at the terminal part of the sporophyte. It is developed at the apical region of the seta and is covered by the calyptra. It provides support and conducts water and nutrients to the developing capsule.
At the tip of leaf: Incorrect answer
The adult gametophyte or gametophyte is differentiated into rhizoids, axis or stem, and leaves. Leaves are sessile, oblong-ovate in shape, and have an entire margin and a pointed apex. They are arranged spirally on the branches and stem.
At the tip of the gametophyte: Correct Answer
Sexual reproduction in Funaria is oogamous. Sex organs are borne on leafy gametophores in terminal clusters. The male reproductive structure is known as antheridium while that of the female is called archegonium. The main shoot of the leafy gametophyte bears antheridia while lateral branches develop the archegonia. This ensures cross-fertilization.
Hence, the correct answer is option (D).
Note: Water is essential for fertilization. After fertilization, protonema develops from the spores in the capsule. The development of the sex organs is found to occur at the gametophyte tip in funaria.