BIOL 1001 : Exam 4 Study Guide
Document Summary
Mitosis does indeed take place during m phase, but m phase is shorter than interphase; cells spend most of their time in interphase. After dna replication is completed each new dna double helix consists of one old dna strand and one new dna strand. The first step of dna replication is unwinding the dna double helix. (helicase) The action of helicase creates replication forks and bubbles. A replication fork is the transition region between paired and unpaired dna strands. New dna strands are complementary to the 3" to 5" strands assembled in short segments because dna polymerase can assemble dna only in the 5" to 3" direction. Since dna polymerase can assemble dna only in the 5" to 3" direction, the new strand complementary to the 3" to 5" strand must be assembled in short. 5" to 3" segments, which are later joined together by ligase.
