Question

Consider the following statements with reference to criterion/criteria used in the classification of plants in the engler and Prantl's system.
a. The families were arranged according to the increasing complexity of flower and fruit.
b. In flowering plants absence of perianth was considered as a primitive character
c. Monocots were considered to be more primitive than dicots
d. Unisexual flowers were derived from bisexual flowers.
Which of the statements given are correct?

• A. $1$ and $2$
• B. $1$ and $4$
• C. $1,2$ and $3$
• D. $2,3$ and $4$

Answer 1

The correct option is A $1$ and $2$

1. In the rules of nomenclature, families are arranged according to the arrangement of the complexity of flower (position of the gynoecium, the arrangement of anthers etc) and fruit (originated from ovary, or from thalamus ).
2. Perianth means the fusion of calyx and corolla (lily) but similar structure also found in mosses and liverworts (bryophytes) and as these are the primitive plant it is supposed that perianth is a primitive character.
3. Monocots were considered more advanced than dicots in the way of photosynthesis they have more advance system and are called C${}_4$ plants and their vascular bundles, the arrangement of leaves etc are much different and evolved the dicots.
4. Plants adopted unisexuality and evolved from bisexuality to prevent genetic depression it is one of the most common methods of prevention of Autogamy and geitonogamy.

So the correct option is "1 and 2".