Question

Read the following statements.
(a) The male or female cones or strobili are born on the same tree in Pinus.
(b) In Cycas, male cones and megasporophylls are borne on different plants.
(c) Stem of Cycas is branched and Cedrus is unbranched.
(d) In gymnosperms generally tap roots are found.
Select the correct statements
A. a,b
B. a,b,d
C. a,b,c
D. c,d

Answer 1

Hint:-Gymnosperms are plants usually found in temperate regions. These plants do not bear flowers or fruits. Their ovule is not confined by an ovary wall hence; the Greek-derived translation of their name is naked seed. Gymnosperms can be classified into- Coniferophyta, Cycadophyta,Ginkgophyta,Gnetophyta.

Complete step-by-step solution:-Pinus belongs to the family of pines. They are cone-bearing plants. The trees belonging to this family have needle-like leaves. Most conifers are monoecious, the female and male cones are found in the same plant.Cycas belongs to the Cycadophyta category. These plants can reproduce via sexual as well as vegetative means. For the sexual reproduction phase, Cycas produce a single male cone every year. Cycas produces a good number of megasporophylls. But unlike most conifers in case of Cycas, the male and female cones are borne on separate trees. Cycas are dioecious. Stems for most gymnosperms are erect and branched, the only exception being Cycas. Cycas has an unbranched stem. Cedrus / Cedar has a branched stem system. Gymnosperms usually have a tap root system. There is one central root from which smaller roots branch out. There is a distinct feature seen in the taproot system of certain gymnosperms. Some of them can function symbiotically with fungus and algae. Mycorrhizal roots are roots that interact with certain species of fungus. Special roots called coralloid roots are the ones that have the presence of blue-green algae which helps in nitrogen fixation.
From this, we can conclude that the correct option is (B).

Note:- Gymnosperms have evolved from Pteridophytes. Gymnosperms have a haplodiplontic life cycle; it alternates between the gametophyte and sporophyte stages. Gymnosperms share few features with angiosperms such as being heterosporous (producing both megaspores and microspores), having a predominant sporophytic phase. Cones or strobili are formed when the seeds of the plant are exposed on the sporophylls.