Question

Angiosperms and gymnosperm resemble in having
A. Vessel in wood
B. Mode of fertilization
C. Siphonogamy
D. Nature of endosperm

Answer 1

Hint: Angiosperms and gymnosperms both are seed-bearing plants. Few similarities are found in them like mode of nutrition as both are autotrophic. They have similarities because they may have shared a common ancestor.

Complete answer:
Angiosperms are plants that produce flowers and bear their seeds in fruits while gymnosperms are flowerless plants that produce cones and seeds. Angiosperms and gymnosperms share some similarities because they may have shared a common ancestor.

> Option A is vessels in wood. The vessel wall is commonly found in angiosperms and it is absent in gymnosperms. This is probably because less water is required in non - flowering plants.

> Option B is mode of fertilization. In gymnosperms, the male gametophyte is the pollen grain and ovule is female gametophyte. The ovule becomes a seed and escapes the embryo and endosperm in a seed coat while in angiosperms the ovary containing the ovules develops into a fruit after fertilization. So, they have different modes of fertilization.

> Option C is Siphonogamy. Siphonogamy is a process in the plants in which pollen tubes are developed for the transfer of the male cells to the eggs. It is found in both gymnosperm and angiosperm. So, we can say siphonogamy is common between angiosperm and gymnosperm.

> Option D is the nature of endosperm. In Angiosperms, endosperm forms by double fertilization, one sperm nucleus fertilizes the egg and forms the embryo and the other sperm nucleus fuses with the two polar nuclei and produces a triploid cell (3n). This triploid cell is developed into a real endosperm while Gymnosperms do not have double fertilization. There are two sperm nuclei as well, but one of them degenerates. In consequence, there is no real endosperm.

Hence, The correct answer is option (C).

Note: The angiosperm and gymnosperms also resemble in mode of nutrition. Both are autotrophs and make their food by photosynthesis, in which $CO_2$ converts into glucose in the presence of sunlight.