LIFESCI 1 Lecture Notes - Lecture 11: Cytoskeleton, Chromosome, Light-Dependent Reactions
Document Summary
Bacteria = prokaryotic: no membrane bound nuclei, no energy-producing organelles, no sex, single circular chromosome = dna called plasmids. Photosynthetic bacteria = may have internal membranes: light reactions of photosynthesis take place in association with membranes in cytoplasm. Cell wall = structure support made of peptidoglycan (polymer of sugar of and amino acids) Most though that bacteria lacked the cytoskeletal framework that organizes cytoplasm in eukaryotic cells: now, we know: bacteria have internal proteins that determine shape, polarity, and spatial properties. Also can have thick walls with many peptidoglycan layers and thin walls with an outer layer of lipids. Photosynthetic bacteria get co2 with diffusion, and respiring bacteria get o2 and small organic molecules with diffusion. A small cell = more surface area in proportion to the volume. Therefore, interior parts of the cell = closer to the surrounding environment than larger cells.
