The enzyme helicase unwinds the dna duplex. which of the following is likely to be true?
a) a pre-existing 3'oh is required for helicase to work
b) helicase uses energy from atp hydrolysis
c) helicase is itself made of rna
d) energy is released when the dna helix is unwound.

B) Helicase uses energy from ATP Hydrolysis

Explanation:

Helicase's primary function is to separate the annealed nucleic acid strands. It is a motor protein and moves directionally along the phosphodiester backbone. It usually separates strands of double helix DNA or self annealed RNA. It used the energy from ATP hydrolysis and breaks hydrogen bonds between nucleotide bases.

In human body 95 types of helicases are found. They have sequence motifs required for ATP binding, ATP hydrolysis and translocation along nucleic acid phosphodiester backbone. The variable portion in their amino acid sequence imparts specific feature to each helicase.

the answer is false?

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.