Freebase(0.00 / 0 votes)Rate this definition: Bollard. A bollard is a short vertical post. Originally it meant a post used on a ship or a quay, principally for mooring. The word now also describes a variety of structures to control or direct road traffic, such as posts arranged in a line to obstruct the passage of motor vehicles.
Which of the following events occurs directly after a DNA molecule is unzipped? A. Mismatched nucleotide bases are identified and replaced. B. Free-floating nucleotides pair up with exposed bases.hich of the following events occurs directly after a DNA molecule is unzipped? A. Mismatched nucleotide bases are identified and replaced. B. Free-floating nucleotides pair up with exposed bases.
What enzyme unwinds DNA? A: The powerful enzyme DNA helicase unwinds the double strands of DNA by breaking the bonds between each of the complementary bases. These bases are held together by strong hydrogen bonds, but in breaking these, DNA helicase creates two single-stranded DNA molecules. Continue Reading.