Living organisms perpetuate themselves through DNA replication and cell division. DNA replication occurs in all lifeforms, a process of semiconservative replication in which each strand of the original DNA molecule serves as a template for the production of the complementary strand. Cell division usually occurs within the context of a larger cell cycle. Prokaryotes undergo a process celled binary fission. While binary fission is conceptually a simple process, its underlying biochemical and genetic mechanisms are a major research area. In eukaryotes, there are two distinct types of cell division. In mitosis each daughter cell is genetically identical to the parent cell. Meiosis is a reproductive cell division. In meiosis, the number of chromosomes is reduced by half, producing haploid gametes.
The genetic and biochemical processes underlying DNA replication and the cell cycle are major focuses for the MCAT. There is a large conceptual vocabulary to be mastered. For example, in just the topic of DNA replication the list of enzymes you need to be familiar with includes DNA helicase, DNA polymerase, DNA clamp, single strand binding proteins, topoisomerase, DNA gyrase, DNA ligase, primase, and telomerase. Like certain other topics in molecular biology, biochemistry, and physiology, it's best to start early in review and have more than one pass through this material. Multiple study cycles spaced out over time are more effective for learning and retention than a single, more intense period of dedicated study.
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Conceptual Vocabulary Self-Test
Basic Terms Crossword Puzzle
Basic Puzzle Solution
Conceptual Vocabulary for DNA Replication, Repair and Cellular Reproduction