LO19-原核细胞分裂.docx

Hello and Welcome In this online session,you will learn about Continuity of Life: Cell Division -Prokaryotes GO Page 1/13 NANYANG TECHNOLOGICAL UNIVERSITY School of Biological Sciences Learning Objectives At the end of the session,you should be able to: Describe the stages of prokaryotic cell d...

Hello and Welcome In this online session,you will learn about Continuity of Life: Cell Division -Prokaryotes GO Page 1/13 NANYANG TECHNOLOGICAL UNIVERSITY School of Biological Sciences Learning Objectives At the end of the session,you should be able to: Describe the stages of prokaryotic cell division; Recognise the characteristics of replication of circular DNA;and Describe the process of forming two daughter cells. Page 2/13 Cell division in prokaryotes takes place in two stages,which together make up a simple cell cycle. Cell division in prokaryotes takes place in two stages,which together make up a simple cell cycle. Split the cell in two to form daughter cells This process is called binary fission. School of Biological Sciences Start Prokaryotic Cell Cycle Sequence School of Biological Sciences X Origin of replication Prokaryotic chromosome: Double-stranded DNA 10>2>3 >4 5 67 Replication of DNA 1>20>3 >4 5 6 7 Interwound Circular Chromosomes 1>20>30>4 5>6 70 Chromosomes are resolved (separated)by a process known as Chromosomal Resolution Chromosomes are resolved (separated)by a process known as Chromosomal Resolution Division of Cell 1>20>3 Division of Cell Division of Cell daughter cells 1>20>3 >45>67 NANYANG TECHNOLOGICAL UNIVERSITY School of Biological Sciences Take Home Messages In this section on Cell Division -Prokaryotes,you need to take home the following messages: 1.Cell division in prokaryotes takes place in two stages:DNA replication and binary fission. 2.The circular DNA of prokaryotes starts unwinding from the origin of replication and proceeds to copy DNA in both directions. 3.The interwound chromosomes that are formed need to be resolved. 4.Cell pinching and deposition of new wall materials lead to formation of two daughter cells,each with one chromosome. Page 8/13