1E2.1 Lesson - DNA Replication

1B1 Macromolecule Elements and Monomers

• Carbohydrates

  • CHO 1:2:1

    • Monosaccharides

• Lipids

  • CHO

    • Fatty Acids and Glycerol

• Proteins

  • CHON

    • Amino Acids

• Nucleic Acids

  • CHOPN

    • Nucleotides

1B1 Nucleic Acids and Proteins

Nucleic Acids

• Stores and transmits genetics information

• Made of nucleotides (monomer - building block)

• created by DNA replication

• Elements CHOPN
  

​Double Helix

1B1, 3C1 Nucleic Acid Monomers

DNA

• DNA nucleotide

  • deoxyribose sugar

  • phosphate group

  • nitrogen bases

    • A, T, G, or C

    • Thymine
      

RNA

• RNA nucleotide

  • ribose sugar

  • phosphate group

  • nitrogen bases

    • A, U, G, or C

    • Uracil
      

1B1 DNA Structure

DNA Double Helix

• Backbone (sides) - B

  • phosphate group and deoxyribose sugar

• Rungs (middle) - A

  • two nitrogen bases of nucleotides

  • joined together with a hydrogen bond - C

  • A (hydrogen bond) T

  • G (hydrogen bond) C

• Order of the nucleotides (horizontal rungs) is where the information to make a protein is stored - ATG-CGT-GAT

​C

​B

​A

DNA, Genes, Chromosomes

CHROMATIN

• DNA wound up around small proteins

• Form of DNA during Interphase

Replicated CHROMOSOME

• two identical strands of chromatin condensed (coiled up) and joined at a centromere

• Form of DNA during Mitosis

DNA, Genes, Chromosomes

GENE

• small section of DNA

• information to make one protein

LOCUS

• location of a gene on a chromosome

DNA Complements

DNA

• Adenine only bonds with Thymine

• Guanine only bonds with Cytosine

• DNA complement of

• ATC-GCC-TAA is

• TAG-CGG-ATT

​Order of the nucleotides (horizontal rungs) is where the information to make a protein is stored - ATG-CGT-GAT

DNA Replication

• DNA Replication - copy of DNA is made

• S -Phase of Interphase

• Semiconservative - half of the original DNA is saved and used in the new DNA strands

Must occur before mitosis (cell division)

• Ensures daughter cells have identical copy of parent cell's DNA

STEPS:

• Enzymes unwind and unzip DNA

• Free DNA nucleotides attach to exposed bases

• Two new strands are formed

• Enzymes zip the new strands back up