12.2 Chromosomes and DNA Replication Notes Nevada State Science Content Standard: L.12.A.2 Students know DNA molecules provide instructions for assembling protein molecules. E/S Objective: Student will make the connections with occurrences during DNA replication. Set: Last time we learned what DNA is and what it is made of. Today we will learn how it is made. Key Vocabulary Chromatin – Histone – Replication – DNA polymerase – In prokaryotes DNA is found in the cytoplasm. In eukaryotes DNA is generally found in the nucleus. Histone – a protein molecule around which DNA is tightly coiled in a chromatin (p 296) During mitosis, the DNA molecules become more tightly coiled. Replication – copying process by which a cell duplicates its DNA (p 299) DNA replication results in two DNA molecules each with one new strand and one original strand. Compare the picture on page 298 to a broken zipper. DNA polymerase – an enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule (p 299)