Question

Gemmae are present in:

• A. Mosses
• B. Pteridophytes
• C. Some Gymnosperms
• D. Some Liverworts

Hint:

Gemmae are referred to as green, multicellular asexual buds. It is produced by some liverworts like Marchantia. Mosses reproduce vegetatively by fragmentation and budding of protonema.

Answer 1

The Correct Option is D

Gemmae are formed in some liverworts like Marchantia.

The gemmae are referred to as small discs of haploid tissue which can directly give rise to new gametophytes. A gemma (plural gemmae) is either a single cell or a mass of cells, or a modified bud of tissue, that separates from the parent and develops into a new individual. The production of gemmae is a means of widespread asexual reproduction in both liverworts and mosses. In liverworts such as Marchantia, the flattened plant body (thallus) is a haploid gametophyte with gemma cups scattered about its upper surface.

Hence, the correct answer is option D.

Answer 2

Reproduction can be classified into two types: asexual and sexual reproduction. Asexual reproduction involves the production of offspring through the simple division of cells, and it is commonly observed in single-cell organisms. This type of reproduction does not involve the fusion of gametes, and the offspring produced are genetically identical. Asexual reproduction is further classified into binary fission, budding, fragmentation, and sporogenesis. In the life cycle of plants, the spore-producing process is referred to as sporophyte. Plants have two reproductive stages: sexual and asexual.

These two stages are segregated into the sporophyte and gametophyte through meiosis and fertilization. During the sporophyte phase, plants produce diploid (2n) spores that later develop into gametophytes and eventually into spores. Gemmae production is a widespread method of asexual reproduction in both mosses and liverworts. In liverworts like Marchantia, the flat plant body or thallus is a haploid gametophyte with gemma cups scattered in the upper part. The gemma cups are cup-like structures containing gemmae, which are small discs of haploid tissue. Gemmae directly give rise to gametophytes and are dispersed from gemma cups by rainfall. They may also be formed as outgrowths from the gametophyte portion and are referred to as exogenous gemmae. 

Hence, the correct answer is option D.