Question

How many of the following sentences are correct?
(i) Polycarpic plants are always perennial or biennial.
(ii) Annual plants show clear-cut vegetative, reproductive and senescent phases.
(iii) All perennials have inter flowering period as a part of the juvenile phase.
(iv) The male and female gametes in flowering plants are produced in embryo sac.

• A. Four
• B. Two
• C. Zero
• D. One

Answer 1

Answer: (D)

Only (ii) statement is correct.
Monocarpic plants: They are plants which flower only once in their life. After flowering, they produce fruits and die. All annuals (E.g., wheat, rice, marigold) and biennial plants (E.g., radish, carrot, henbane), are monocarpic. A few perennial plants are also monocarpic. Certain bamboo species (E.g., Bambusa tulda, Melocanna bambusoides) live vegetatively for 50 – 100 years, flower and fruit abundantly and then die. Annuals are plants that go through their entire lifecycle in one growing season and they show clear-cut vegetative, reproductive and senescent phases. Biennial are plants whose lifecycle spans two years, so they flower and produce seeds in their second year. Perennials are plants that can survive and live for more than two years.
Polycarpic Plants: They are perennial plants which after reaching maturity, flower repeatedly at intervals, e.g., Mango, Apple, Jackfruit, Grapevine, Orange. Very few perennial plants bear flowers throughout the year, e.g., China rose (Shoe flower). The period between two flowering phases is called 'inter flowering period' which is used for building up resources and is, therefore, a recovery phase. It is not the juvenile phase but is part of the mature phase.
The male gamete (pollen) is produced in the microsporangium inside the anther lobe and hence the process is also called 'microsporogenesis'. The female gamete or ovum, produced in the ovule (megasporangium) by the process of megasporogenesis.