Life Sci: DNA Structure and Replication

DNA is a double helix composed of two strands of nucleotides, which include a phosphate group, a sugar (deoxyribose), and nitrogenous bases (adenine, thymine, cytosine, guanine).

The nitrogenous bases in DNA are adenine (A), thymine (T), cytosine (C), and guanine (G).

In DNA, adenine pairs with thymine (A-T) and cytosine pairs with guanine (C-G).

DNA helicase is an enzyme that unwinds the DNA double helix during replication, separating the two strands.

Okazaki fragments are short sequences of DNA nucleotides synthesized on the lagging strand during DNA replication.

RNA primase synthesizes a short RNA primer that provides a starting point for DNA polymerase to begin DNA synthesis.

DNA polymerase is the enzyme responsible for adding nucleotides to the growing DNA strand during replication.

Single-strand binding (SSB) proteins bind to and stabilize single-stranded DNA during replication to prevent it from re-annealing.

Rosalind Franklin's X-ray diffraction images provided critical evidence of the helical structure of DNA.

The leading strand is the DNA strand that is synthesized continuously in the same direction as the replication fork.