Question

Select the mismatch.
A. Equisetum - Homosporous
B. Pinus - Dioecious
C. Cycas - Dioecious
D. Salvinia - Heterosporous

Answer 1

Hint:The term “Monoecious” also referred to as “single house,” means that male and female flowers are both found on a single individual. This in contrast to dioecious, which is referred as “double house” means that male flowers are on one different plant and female flowers are on another plant.

Complete answer:
As we already discussed, Monoecious plants are those plants which bear both sperm and eggs on the same gametophyte. Whereas, Dioecious plants are those that have gametophytes that produce only sperm or eggs but never both. These terms are used very much but not exclusively in the context of bryophytes. In both types of gametophytes whether monoicous or dioicous produce gametes in gametangia by mitosis rather than meiosis. Therefore, sperm and eggs are genetically identical with their parent gametophyte. The state of being monoecious is called monoecy, and dioecious state is called dioecy.
Now let’s discuss Homo-sporous plants, which produce only one type of spore.
On other hand, heterosporous plants have or produce two types of spores (which are namely, microspores and megaspores), develop into male gametophyte and female gametophyte respectively
Now Remember, Equisetum produces the same type spore (homosporous) whereas, Salvinia produces different types of spores (heterosporous). Pinus is a gymnosperm which possesses both male and female reproductive parts and is therefore called monoecious. On other hand, Cycas possess either male or female reproductive parts, so it is dioecious.

Additional information:
It is important to know, Dioecy is a character of a species, which means that it has distinct male and female individual organisms. Therefore, Dioecious reproduction is biparental reproduction.

Thus, the correct answer is option (B) Pinus is not dioecious.

Note:- Keep in mind, that depending on absence or presence of the bisexual flowers, the plants can be divided as monoecious and dioecious. In monoecious plants always flowers are unisexual, but both the pistillate and staminate flowers are present. Note that, Pistillate flowers are referred to as female flowers and staminate flowers are male flowers. In case dioecious plants, either one type which is pistillate flowers or staminate flowers are present.