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Learn about bacterial binary fission, a process by which bacteria reproduce and divide into two identical cells.
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Course: AP®︎/College Biology > Unit 6. Lesson 1: DNA and RNA structure. Introduction to nucleic acids and nucleotides. DNA. Molecular structure of DNA. Molecular structure of RNA. Nucleic acids. Prokaryote structure. DNA and RNA structure.
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Unit 6: Structure of a cell - Khan Academy
Unit 1 Intro to biology. Unit 2 Water, acids, and bases. Unit 3 Macromolecules. Unit 4 Elements of life. Unit 5 Energy and enzymes. Unit 6 Structure of a cell. Unit 7 More about cells. Unit 8 Membranes and transport. Unit 9 More about membranes.
Prokaryote classification and diversity - Khan Academy
Key points: The two prokaryote domains, Bacteria and Archaea, split from each other early in the evolution of life. Bacteria are very diverse, ranging from disease-causing pathogens to beneficial photosynthesizers and symbionts. Archaea are also diverse, but none are pathogenic and many live in extreme environments.
Meiosis | Cell division | Biology (article) | Khan Academy
Since cell division occurs twice during meiosis, one starting cell can produce four gametes (eggs or sperm). In each round of division, cells go through four stages: prophase, metaphase, anaphase, and telophase.
Apply: cell division and organism growth - Khan Academy
Apply your understanding of cell division and organism growth in this set of free practice questions aligned to NGSS standards.
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Course: AP®︎/College Biology > Unit 2. Lesson 8: Cell compartmentalization and its origins. Prokaryotic and eukaryotic cells. Intro to eukaryotic cells. Endomembrane system. The endomembrane system. Endosymbiosis theory. Mitochondria and chloroplasts. Prokaryotes and eukaryotes review.
Surface area to volume ratio of cells (video) | Khan Academy
In order to stay alive, cells exchange resources, waste, and energy with their environments. This exchange happens across the cell membrane. As the volume of a cell increases, the ratio of surface area to volume decreases, making these exchanges less efficient.
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What is antibiotic resistance? Bacterial meningitis. Virus structure and classification. Viral replication: lytic vs lysogenic. Retroviruses. Subviral particles: viroids and prions.