Tiêu đề Cell Cycle Handout.pdf ✅

Unit 1: Introduction to Genetics and Cell Biology 1 Topic 3: The Cell Cycle, Mitosis and Meiosis Cell division is one of the most important features of living things. It serves three main functions: reproduction, growth and development, and tissue renewal. Prokaryotes and simple eukaryotes make use of cell division, specifically binary fission, as a means of asexual reproduction. Multicellular eukaryotes use cell division during growth and development. For example, humans all develop from a single fertilized egg cell. Lastly, whenever there is tissue damage in organisms, cell division is used to repair and renew damaged tissues. Cell division is a process that is under the cell cycle. This chapter focuses on the cell cycle and also includes a review of mitosis and meiosis Learning Objectives At the end of this topic, you will be able to: a. identify the phases of the cell cycle and describe what occurs in each stage. b. identify the stages in mitosis and what occurs in each stage. c. identify the stage in meiosis and what occurs in each stage. d. be able to state the differences between mitosis and meiosis Presentation of Content The cell cycle The cell cycle is a series of events that lead to cell division and the production of two daughter cells, each containing chromosomes identical to the parent cell. Cell division is also called mitosis. There are several events that occur before a cell reaches the mitotic stage. The cell cycle is essentially divided into 2 phases: interphase and the mitotic phase (M phase). Interphase is further divided into gap phases, (G1 and G2) and the synthesis (S phase). The M phase is further divided into mitosis and cytokinesis where mitosis is divided into prophase, prometaphase metaphase, anaphase and telophase while cytokinesis is the physical division of the cell mass. Any cell that is outside the cell cycle is in the G0 phase. A cell remains in G0 unless it receives signals that it needs to divide. Cell division may be triggered by different factors. Injury to tissue is one such factor. The need to replace the damaged cells starts a cascade of signals that push the cell into interphase. In other cases, there are cells that have to be actively dividing almost all the time. Cell division of such cells begin in their stem cells. Stem cells are cells whose daughter cells are able to produce different types of