The Cell Cycle and DNA Replication

The cell cycle is here to produce two new identical cells. It is a cell’s form of reproduction.

Steps of the cell cycle include…

Interphase
- G1 Phase (Everything Except DNA Replicates)
- S Phase (DNA Replication)
- G2 Phase (Cell Double Checks)
Mitosis
- Prophase (Nucleus Disappears)
- Metaphase (Chromosomes “meet” in the center)
- Anaphase (Chromosomes separate to poles by spindle fibers)
- Telophase (Cell forms cleavage furrow in the center)
Cytokinesis (Two new daughter cells)
G0 Phase (Resting Period)
Cells Enter Interphase Again

Cancer is the result of uncontrollable cell division, where cells do not stop dividing. The cell never goes into the G0 phase.

DNA can also be called genetic material or genome. DNA forms a double helix with both of its strands bonded with the use of complementary base pairs like adenine and thymine or guanine and cytosine.

Nitrogenous bases carry the genetic code. They are bound by weak hydrogen bonds. All living organisms contain DNA. The order of the bases determines the order of amino acids which create a protein. The protein determines the trait being made.

DNA is a polymer and a nucleic acid. Its monomers are nucleotides. Nucleotides contain three parts. Phosphates, sugars, and nitrogen bases.

DNA Replication occurs during the S phase. “S” stands for DNA synthesis. It is the reason why each cell has the same DNA after the cell cycle.

The enzyme helicase unzips the DNA and breaks hydrogen bonds.
The enzyme DNA polymerase attaches free floating nitrogen bases (Adenine, Thymine, Guanine, Cytosine) to their complementary bases.
Two semi-conservative strands are formed that are exact copies of each other.