Nitrogen Base | Makes up the "rungs" of the DNA ladder |
Sugars and phosphates | Alternate along the "sides" of the DNA ladder |
Nucleotide | Made up of a pentose sugar, phosphate, and a nitrogen base |
Double Helix | The shape of the DNA molecule |
RNA | uses the code from DNA to make proteins |
Adenine always pairs with | Thymine |
Cytosine always pairs with | Guanine |
Trait | A characteristic that an organism can pass on to its offspring through its genes. |
Gene | A segment of DNA on a chromosome that codes for a specific trait |
Chromosomes | thread-like structures made of bundled up DNA molecules that contain the genes |
How is DNA different from RNA? | DNA has Thymine, RNA has Uracil
DNA has deoxyribose, RNA has ribose
DNA is a double helix, RNA is a single helix |
Hydrogen bond in DNA | A weak chemical bond that holds together, the complementary
strands of DNA. The hydrogen bonds and the nitrogen bases form
the rungs of the DNA. |
Helicase | Unzips DNA |
Primase | An enzyme that joins RNA nucleotides to make the primer using the parental DNA strand as a template. |
DNA Polymerase | Builds new DNA strand by adding complementary nucleotides |
Ligase | An enzyme that connects (Glues) two fragments of DNA to make a single fragment |
Leading Strand | The new continuous complementary DNA strand synthesized along the template strand in the mandatory 5' to 3' direction. |
Lagging Strand | The strand that is synthesized in fragments using individual sections called Okazaki fragments. from 3' to 5' |
DNA Replication Steps | 1) Helicase- unwinds the parental double helix
2) DNA topoisomerase - upstream of helices alleviating torsional strain
3) Single-strand binding proteins (SSBP) stabilize unwound DNA, aided by DNA gyrase.
4) Primase synthesizes a short RNA primer for DNA polymerase
to bind to in the 5' to 3' direction to start replication on each strand.
5) DNA polymerase synthesizes the leading strand in 5' to 3' direction while the lagging strand is made discontinuously by primase making short pieces and then DNA polymerase extending these to make Okazaki fragments.
6) DNA ligase joins the Okazaki fragments together |
Antiparallel | The opposite arrangement of the sugar-phosphate backbones in a DNA double helix. |