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Explore the mechanisms of asexual and sexual reproduction in prokaryotic organisms and protists, from binary fission to bacterial conjugation. Learn about the origin of replication, plasma membrane dynamics, and chromosome replication in E. coli cells. Discover the significance of budding in cellular division and regeneration in Platyhelminthes. Dive into the fascinating processes of bacterial transformation and transduction, where genetic material is transferred and integrated into bacterial genomes through bacteriophages. Gain insights into the cell cycle checkpoints, including G2 and mitosis, in sexual reproduction.
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Organismal DevelopmentPart 1 Prokaryotic Organisms and Protists
Cell wall Origin of replication Plasma membrane E. coli cell Bacterial chromosome Chromosome replication begins. Soon thereafter, one copy of the origin moves rapidly toward the other end of the cell. Two copies of origin Asexual – Binary Fission Origin Origin Replication continues. One copy of the origin is now at each end of the cell. Replication finishes. The plasma membrane grows inward, and new cell wall is deposited. Two daughter cells result.
Cell wall Origin of replication Plasma membrane E. coli cell Bacterial chromosome Chromosome replication begins. Soon thereafter, one copy of the origin moves rapidly toward the other end of the cell. Two copies of origin Asexual – Binary Fission Origin Origin Replication continues. One copy of the origin is now at each end of the cell. Replication finishes. The plasma membrane grows inward, and new cell wall is deposited. Two daughter cells result.
Transformation Bacterial Transformation – a type of asexual bacterial reproduction where genetic material is passed from bacteria to bacteria. Bacterial plasmids are modified and then placed into a new bacteria. This modified bacterial plasmid gives the bacteria new and novel functions.
Bacterial Transduction – a form of bacterial asexual reproduction that is carried out by a virus (bacteriophage). Bacteriophages can carry full strands of fragments of DNA and will insert this DNA into the genome of bacteria. Eukaryotic viruses work in a similar fashion and also carry DNA. Once inserted into the genome, this DNA will now be read as part of the original genome. The new bacterial genome will now have new and novel functions. Phage DNA A+ B+ A+ B+ Bacterial Transduction Donor cell A+ Crossing over A+ A– B– Recipient cell A+ B– Recombinant cell
Conjugation in Bacteria Bacterial Conjugation – this is another form of asexual reproduction in bacteria that allows for genetic variation. Two bacteria will become connected by a “sex pillus” and genetic material will be transmitted between the two. The new genetic material will become part of the original genome.
Cell Cycle with checkpoints(Is all going according to plan?)