https://www.khanacademy.org/science/ap-biology/cellular-energetics/photosynthesis/v/photosynthesis-evolution 2023-06-06T10:35:22.92767095Z Photosynthesis evolution Ancient cyanobacteria produced oxygen as a byproduct of photosynthesis, changing the composition of the atmosphere over time in the Great Oxygenation Event. These cyanobacteria also led to the evolution of chloroplasts when they started living inside other cells, a process called endosymbiosis. The cyanobacteria provided the larger cell with sugars from photosynthesis, and the larger cell gave protection and nutrients. video https://cdn.kastatic.org/googleusercontent/AaIAMJ-ZLIGlw2HdbrN6JvJdSqEFm7n7Z-D3rsvLHi9wffhU3IheOQkSlhTSfKkzuxXn4gvZNV1GyGgFu5AHsif6fQ Photosynthesis evolution Ancient cyanobacteria produced oxygen as a byproduct of photosynthesis, changing the composition of the atmosphere over time in the Great Oxygenation Event. These cyanobacteria also led to the evolution of chloroplasts when they started living inside other cells, a process called endosymbiosis. The cyanobacteria provided the larger cell with sugars from photosynthesis, and the larger cell gave protection and nutrients. https://cdn.kastatic.org/ka-youtube-converted/RnHCOBDSSfA.mp4/RnHCOBDSSfA.mp4 488 Bacteria ecology and diversity https://www.khanacademy.org/science/revision-term-1-ka-biology-grade-11/x1474e0ca4285b2f5:week-1/x1474e0ca4285b2f5:biological-classification/e/bacteria 2026-04-08T00:16:02.937952483Z Bacteria Characteristics of bacteria, autotrophic bacteria, heterotrophic bacteria, reproduction in bacteria. Moumita Sen exercise https://www.khanacademy.org/science/ap-biology/gene-expression-and-regulation/dna-and-rna-structure/a/prokaryote-structure 2021-04-29T07:49:14Z Prokaryote structure Overview of prokaryotes (bacteria and archaea). Structural features of prokaryotic cells. article https://www.khanacademy.org/science/health-and-medicine/infectious-diseases/x6e556f83:bacteria-and-viruses/v/bacterial-characteristics-gram-staining 2023-08-17T23:33:36.770424498Z Bacterial characteristics - Gram staining Discover the fascinating world of bacteria! Learn how scientists differentiate bacteria by their shape - cocci, bacilli, and spirilla - and color using the Gram stain method. Learn about similarities and differences in the structure of bacterial cell walls and understand why Gram positive bacteria retain the purple stain while Gram negative bacteria turn pink. video https://cdn.kastatic.org/googleusercontent/E4TW1JvXKcEKlU9YBwaq3X225dqyOiUQYeXqzwFDvQaZRcY6AGEi6ePgtfTe-Mv_b8ExAwAKd9QwnVCr5Ussxc0 Bacterial characteristics - Gram staining Discover the fascinating world of bacteria! Learn how scientists differentiate bacteria by their shape - cocci, bacilli, and spirilla - and color using the Gram stain method. Learn about similarities and differences in the structure of bacterial cell walls and understand why Gram positive bacteria retain the purple stain while Gram negative bacteria turn pink. https://cdn.kastatic.org/ka-youtube-converted/FgsgpoFhleA.mp4/FgsgpoFhleA.mp4 445 Bacteria ecology and diversity