Occurrence of triploid (3n) primary endosperm nucleus is a characteristic feature of
Algae
Gymnosperms
Angiosperms
Bryophytes
C.
Angiosperms
Endosperm nourishes embryo in seed plants. In gymnosperms, it represents the female gametophyte and is haploid (n). In angiosperms, it is a special tissue which is formed as a result of fusion of a male gamete with diploid secondary nucleus of the central cell. The fusion product is primary endosperm cell having a triploid (3n) endosperm nucleus.
Assertion: Presence of large amounts of nutrients in water body causes excessive growth of planktonic algae.
Reason: It is due to biomagnification.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Which of the following groups of algae produces algin?
Phaeophyceae and Chlorophyceae
Rhodophyceae and Phaeophyceae
Chlorophyceae and Rhodophyceae
Phaeophyceae only
Which of the following is not an invasive species?
Parthenium hysterophorus
Nelumbo (lotus)
Lantana camara
Eichhornia crassipes
Assertion: The leaves in gymosperms are well adapted to with stand extremes of temperature, humidity and wind.
Reason: Unlike bryophytes and pteridophytes, in gymnosperms the male and female gametophytes do not have an independent free-living existence.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Assertion : Sphagnum is slowly carbonised, compressed and fossilised over thousands of years to produce a dark spongy mass called peat.
Reason : Peat helps to keep soil porous and it also improves water holding capacity of the soil.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
Gametophyte and sporophyte are independent of each other in which of the following groups?
Pteridophytes
Angiosperms
Gymnosperms
Bryophytes
In which of the following sets of organisms, does the external fertilization occur?
Echinodermata and mosses
Hemichordata and ferns
Amphibians and algae
Reptiles and gymnosperms
Assertion: In basidiomycetes, basidiospores are produced endogenously in the basidium.
Reason: In ascomycetes, ascospores are produced exogenously in ascus.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
