Basics of DNA

DNA REPLICATION: Before the lagging-strand DNA exits the replication factory, its RNA primers must be removed and the Okazaki fragments must be joined together to create a continuous DNA strand. The first step is the removal of the RNA primer. RNAse H, which recognizes RNA-DNA hybrid helices, degrades the RNA by hydrolyzing its phosphodiester bonds. Next, the sequence gap created by RNAse H is then filled in by DNA polymerase which extends the 3' end of the neighboring Okazaki fragment. Finally,…

Terms in this set (...)

DNA Replication
the process of making identical copies of DNA before cell division
Semiconservative replication
Each half of an original DNA molecule serves as a templete for a new strand, and the two new DNA molecules each have one old and one new strand.
DNA helicase
An enzyme that unwinds the double helix of DNA and separates the DNA strands in preparation for DNA replication.
DNA Polymerase
Enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule
direction of continuous replication
5' to 3' direction; In DNA synthesis, DNA strands always elongate in a 5' to 3' direction.
double helix
The form of DNA, referring to its two strands wound into a spiral shape.
deoxyribonucleic acid
A molecule that consists of nucleotide monomers used for transmitting genetic information from one generation to the next
nucleic acid
Macromolecules that includes DNA and RNA.
A subunit of nucleic acids formed from a simple sugar, a phosphate group, and a nitrogenous base.
A nitrogen base found in DNA and RNA. It pairs with thymine in DNA and with uracil in RNA
A nitrogen base found in both DNA and RNA; pairs only with cytosine.
A nucleotide that pairs with adenine. Found only in DNA.
A nitrogenous base found in DNA and RNA; pairs with guanine
hydrogen bond
A weak chemical bond used to hold complementary base pairs together
base pairs
Any of the pairs formed between complementary bases in the two nucleotide chains of DNA, such as A-T and C-G (DNA); A-U and C-G (RNA)
5' or 3'
the number stands for where on the deoxyribose sugar is attached to a phosphate