Multiple Choice QuestionsPests which only feed and oviposit on crop are called
major pests
minor pests
accidental pests
occasional pests
In which stage of its life cycle, the silk moth begins to produce silk fibre?
3rd instar larva
4th instar larva
5th instar larva
Pupa
Which of the following be named for DNA produced from RNA?
A- DNA
B- DNA
C- DNA
Z- DNA
C.
C- DNA
The DNA synthesized on template of RNA by the enzyme reverse transcriptase is called complementary DNA (C-DNA).
A-DNA is a right-handed double helix fairly similar to the more common B-DNA form, but with a shorter, more compact helical structure whose base pairs are not perpendicular to the helix-axis as in B-DNA.
In B-DNA, the most common double helical structure found in nature, the double helix is right-handed with about 10–10.5 base pairs per turn. The double helix structure of DNA contains a major groove and minor groove.
Z- DNA is the double helix that has a left- handed rather than the usual right handed twist and the suagr- phosphate backbone followsa zig-zag course.
Increase of BOD in water leads to
increase in the dissolved O2 concentration
decrease in the dissolved O2 concentration
maintenance of dissolved O2 concentration at the same level
no effect on dissolved O2 concentration
Freon gas causing stratospheric O3 depletion is mainly released from
refrigerator
automobile
thermal power plant
steel industry
Switch
