Primary source of allelic variation is

• independent assortment

• recombination

• mutation

• polyploidy

In which one of the following would you expect to find glyoxysomes?

• Endosperm of wheat

• Endosperm of castor

• Palisade cells in leaf

• Root hairs

43.

Which one of the following correctly represents an organism and its ecological niche?

• Vallisneria and pond

• Desert locust (Scistocerca) and desert

• Plant lice (aphids) and leaf

• Vultures and dense forest

Given below is one of the types pyramids.

This type represents

• pyramid of numbers in a grassland

• pyramid of biomass in a fallow land

• pyramid of biomass in a lake

• energy pyramid in a spring

Somaclonal variation appears in

• organisms produced through somatic hybridization

• plants growing in highly polluted conditions

• apomictic plants

• tissue culture raised plants

cDNA probes are copied from the messenger RNA molecules with the help of

• restriction enzymes

• reverse transcriptase

• DNA polymerase

• adenosine deaminase

Double fertilization involves

• fertilization of the egg by two male gametes

• fertilization of two eggs in the same embryo sac by two sperms brought by one pollen tube

• fertilization of the egg and the central cell by two sperms brought by different pollen tubes

• fertilization of the egg and the central cell by two sperms brought by the same pollen tube.

Assertion : In recombinant DNA technology, human genes are often transferred into bacteria (prokaryotes) or yeast (eukaryote).

Reason : Both bacteria and yeast multiply very fast to form huge populations which express the desired gene.

• If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion

• If both Assertion and Reason are true but the Reason is not the correct explanation of the assertion

• If Assertion is true but Reason is false.

• If both Assertion and Reason are false

Assertion : A suspended particulate matter (SPM) is an important pollutant released by diesel vehicles.

Reason : Catalytic converters greatly reduce pollution caused by automobiles.

• If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion

• If both Assertion and Reason are true but the Reason is not the correct explanation of the assertion

• If Assertion is true but Reason is false.

• If both Assertion and Reason are false

Assertion : Methane component of green house gases contributing to global warming is about 20 percent.

Reason : Introduction of multi-point fuel injection engines in automobiles has decreased methane content in the exhausts.

• If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion

• If both Assertion and Reason are true but the Reason is not the correct explanation of the assertion

• If Assertion is true but Reason is false

• If both Assertion and Reason are false