EVERYDAY SCIENCE

Detailed explanation-1: -In ferns, meiosis occurs on the underside of fronds in small structures called sporangia.

Detailed explanation-2: -Life cycle of a moss (genus Polytrichum). The sporophyte generation is dependent on the photosynthetic gametophyte for nutrition. Cells within the sporangium of the sporophyte undergo meiosis to produce male and female spores, respectively.

Detailed explanation-3: -The zygote develops as a multicellular sporophyte, but remains dependent on the female gametophyte. Meiosis takes place in a specialized structure on the sporophyte (the sporangium), producing spores (not gametes!). The spores divide and produce male or female gametophytes. The sporophyte of mosses: a dependent stage.

Detailed explanation-4: -Sporangium of Nephrolepis consists of 16 spore mother cells, which undergo meiosis only once to form haploid cells. The sporangia produce haploid meiospores. As the sporangia mature, the indusium shrivels, so that spore release is unimpeded.

Detailed explanation-5: -In plants, meiosis is initiated in sporogenous cells that are differentiated in ovules and anthers (Bhatt et al., 2001). In each ovule, only a single megaspore mother cell (MMC) surrounded by the somatic nucellar cells is differentiated and then undergoes meiosis (Figure 1).