The gymnosperms (gymnos : naked, sperma : seeds) are plants in which the ovules are not enclosed by any ovary wall and remain exposed, making their seeds naked.
Question 22 of 100
📘 CLASS XI
Coralloid roots associated with N2-fixing cyanobacteria are found in which gymnosperm?
While Pinus roots have a fungal association (mycorrhiza), Cycas possesses small specialized roots called coralloid roots that are associated with N2-fixing cyanobacteria.
Question 23 of 100
📘 CLASS XI
In conifers, needle-like leaves, thick cuticles, and sunken stomata are adaptations to:
In conifers, the needle-like leaves reduce the surface area. Their thick cuticle and sunken stomata also help to reduce water loss, allowing them to withstand extremes of temperature, humidity, and wind.
Question 24 of 100
📘 CLASS XI
In gymnosperms, the highly reduced male gametophyte generation is called:
The microspores develop into a male gametophytic generation which is highly reduced and is confined to only a limited number of cells. This reduced gametophyte is called a pollen grain.
Question 25 of 100
📘 CLASS XI
In which gymnosperm are male and female cones borne on different trees?
In Pinus, male and female cones may be borne on the same tree. However, in Cycas, male cones and megasporophylls are borne on different trees.
Question 26 of 100
📘 CLASS XI
Unlike bryophytes and pteridophytes, the male and female gametophytes in gymnosperms:
Unlike bryophytes and pteridophytes, in gymnosperms, the male and the female gametophytes do not have an independent free-living existence. They remain within the sporangia retained on the sporophytes.
Question 27 of 100
📘 CLASS XI
In angiosperms, the seeds are enclosed in:
In angiosperms, or flowering plants, the seeds are enclosed in fruits, unlike gymnosperms where the ovules are naked.
Question 28 of 100
📘 CLASS XI
The smallest and tallest angiosperms mentioned in the text are respectively:
Angiosperms range in size from the smallest Wolffia to tall trees of Eucalyptus (over 100 metres).
Question 29 of 100
📘 CLASS XI
Which of the following is not a class of Algae?
Algae are divided into three main classes: Chlorophyceae, Phaeophyceae, and Rhodophyceae. Lycopsida is a class of pteridophytes.
Question 30 of 100
📘 CLASS XI
Match the organisms with their plant group: A. Spirogyra - i. Pteridophyte B. Marchantia - ii. Gymnosperm C. Equisetum - iii. Bryophyte D. Pinus - iv. Algae
Spirogyra is an alga. Marchantia is a liverwort (bryophyte). Equisetum is a horsetail (pteridophyte). Pinus is a gymnosperm.
