A nucleotide is a building block of nucleic acids it consists of carbon (pentose) sugar molecule (ribose or deoxyribose) a phosphate group and the bases Adenine (A), Guanine (G), Cytosine, Thymine (T), Uracil (U)
DNA Helicase (enzyme) unwinds/separates the two strands of DNA by breaking the hydrogen bonds between complementary base pairs, forming a Replication Fork
Single-strand binding proteins attach to each strand and prevent them from reforming a double helix
The leading strand is synthesized continuously in the 5’ → 3’ direction by DNA Polymerase (key enzyme that makes new strands of DNA)
The lagging strand is synthesized discontinuously. Primase synthesizes a short RNA primer (short sequences 10-15 nucleotides long), which is extended by DNA polymerase to form an Okazaki fragment
RNA primer is replaced by DNA by another DNA polymerase DNA ligase joins the Okazaki fragment to the growing strand
DNA copy of an mRNA molecule; mRNA can be copied into cDNA by the enzyme reverse transcriptase (for instance, when preparing a cDNA library).
Refers to the 5′ and 3′ directionality of strands of DNA in which the two strands joined together by hydrogen bonds between complementary base pairs are oriented in opposing directions with respect to their polarity.
Process by which DNA is copied; one original (parent) DNA molecule gives rise to two molecules, each of which has one original strand and one new strand
Where does the Charge on DNA come from?
RNA vs DNA
- Double stranded
- Ribose Sugar
What is agarose gel electrophoresis used for?
Why is Agarose used in gel electrophoresis and how does it help the separation of DNA?
Agarose gel is used because it has many different sized bubbles through the gel, the DNA strands slip between these bubbles, the smaller the strand the further it goes. DNA moves toward the positive terminal because DNA has a slight negative charge so it will naturally move away from the negative currents and will move to the positive.
Why do we need to use DNA marker/ladder in agarose gel elctrophoresis?
The DNA marker ladder consists of a set of DNA fragments of know different molecular masses or fragment sizes. This enables you to assign a size to DNA fragments in a test sample by comparing its position after electrophoresis with the fragments in the ladder.
Where do restriction enzymes come from?
come from bacteria; bacteria use them to cut foreign DNA, such as viruses to protect the cell