basal membrane, a sheet of tissue that forms the outer layer of the choroid and lies just under the pigmented layer of the retina. It is composed of elastic fibers in an otherwise thin homogenous layer.asal membrane, a sheet of tissue that forms the outer layer of the choroid and lies just under the pigmented layer of the retina. It is composed of elastic fibers in an otherwise thin homogenous layer.
There are several enzymes that 'unzip' DNA. These enzymes are collectively known as DNA helicases. DNA helicases are helix-destabilizing enzymes that bind to DNA at the origin of replication and break hydrogen bonds, thereby separating the two strands.. Solomon, Eldra P., Linda R. Berg, and Diana W. Martin. Biology. 8th ed. Belmont, CA: Thomson Brooks/Cole, 2008.
The structure of DNA lends itself easily to DNA replication. Each side of the double helix runs in opposite (anti-parallel) directions. The beauty of this structure is that it can unzip down the middle and each side can serve as a pattern or template for the other side (called semi-conservative replication).However, DNA does not unzip entirely.It unzips in a small area called a replication fork, which then moves down the entire length of the molecule. Let's look at the details: 1  An enzyme called DNA gyrase makes a nick in the double helix and each side separates. 2  An enzyme called helicase unwinds the double-stranded DNA.NA Replication. Â­DNA carries the information for making all of the cell's proteins. These proÂ­teins implement all of the functions of a living organism and determine the organism'Â­s characteristics. When the cell reproduces, it has to pass all of this information on to the daughter cells.