Large hydroelectric dams: a. have one of the highest (if not the highest) eroei of any energy source. b. produce no co2 emissions to generate the electricity because nothing is burned. c. do little if any environmental damage. d. a and b. e. a, b, and c.

ANSWER IS D

Large hydroelectric dams has been shown to have one of the highest (if not the highest) EROEI (The energy return on investment) of any energy source. Also, nothing is burned when large hydroelectric dams generate electricity, so they do not produce CO2 emissions. However, by altering  a river's flow and, and by their downstream sediment transport, they often cause great sustained environmental impacts.

you are certainly talking about this picture:

a: is the label of the white square, it is showing the  replication fork, formed by helicase (d) ==> so it is the site of dna separation and replication 

b: is a new dna brand that is following directly the replication fork, so it is continuous ==> built continuously from 5' to 3

c: dna polymerase cannot replicate dna on its own, it needs the of their proteins, and one of them plays the role of a clamp which fixes  the dna with the dna template and increases  the processivity of the enzyme. ==>   stops polymerase from falling off the  template.

d: is the enzyme responsible for forming the replication fork (helicase) ==> unwinds and separates dna into two strands

e: is the delayed strand, it is built  in the opposite sense of the helicase, so dna will be built in fragments ==> built  fragments from 5' to 3 joins

and finally f: is the enzyme that builds  the new dna strand (dna polymerase) ==>   adds nucleotides to make a new dna helix.

credit: gradman555p98x9p

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