BIOL1012 Lecture Notes - Lecture 10: Cytoskeleton, Cell Membrane, Oogonium
Document Summary
Larger than prokaryotes (chapter 6: compartments (s:v ratio; maintain varied internal environments) Mitochondria & chloroplasts: mitosis, diploidy, meiosis & sex. Cell components: cytoplasmic streaming, mitosis (spindle is composed of microtubules) In bacteria the origins of replication move to opposite poles (possibly attached to the plasma membrane) Mitosis: types of mitosis seen in various eukaryotes may provide an indication of how this form of division evolved in eukaryotes, dino agellates chromosomes attach to the nuclear envelope, which remains intact during mitosis. Microtubules pass through cytoplasmic channels in the nucleus. Mitosis: diatoms nuclear envelope stays intact, but microtubules form a spindle within the nucleus and attach to and separate the chromosomes. Asexual reproduction: clonal reproduction that does not enhance genetic variation (no recombination) Budding (a) (common in yeasts & simple animals) Fragmentation and vegetative reproduction (b) (common in algae and plants) Parthenogenesis (direct development of an egg without fertilization) (common in algae & social insects)
