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.
DNA helicase unzip, or separate, a strand of DNA at positions called origins. This means that the hydrogen bonds between complementary base pairs are removed (DNA is double stranded!). When they separate double-stranded DNA into single strands, it allows each strand to be copied (replication).his means that the hydrogen bonds between complementary base pairs are removed (DNA is double stranded!). When they separate double-stranded DNA into single strands, it allows each strand to be copied (replication).