Sure that proteins are end up on the right side sort

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sure that proteins are end up on the right side (sort to different parts of the cell) Peroxisomes : location for redox reaction Membrane-bound organelles (1) 55
Endosomes : involve in exchanging material with the plasma membrane and outside world Lysosomes : degradation (breakdown) of large lipids and proteins stomach of the cell Mitochondria : oxidation of energy molecules to make ATP (oxidative phosphorylation and Kreb’s cycle) Chloroplasts : found in plants and algae. Use sunlight to Membrane-bound organelles (2) 56
How did eukaryotic cells evolve? 57
58 Figure 12-4a 4 th edition, Molecular Biology of the Cell (© Garland Science 2008) EVOLUTION OF THE NUCLEUS Ancesteral cell had DNA tethered to the plasma membrane - Plasma memrane ingression aound DNA - Ingressed membranes completely surround DNA then sever from plasma membrane
Figure 1-31 Molecular Biology of the Cell , Fifth Edition (© Garland Science 2008) Plausible Origin of Eukaryotic Cells •Primordial eukaryotic cells may have been predatorial, eating other cells White blood cell, neutrophil, eating a red blood cell by phagocytosis 59 70326148
Plausible Origin of Eukaryotic Cells Requires change in cell shape driven by the cytoskeleton filaments Likely, nuclear enclosure would be advantageous to protect DNA from entanglement and breakage 60 Primordial pre-eukaryotic cells may have been predatorial , eating other cells The process by which cells eat other cells is called phagocytosis Many current cells do this: from amoeba to our immune cells
Predatorial eukaryotic cells may also explain the origin of mitochondria and chloroplasts 61
Figure 1-33 Molecular Biology of the Cell , Fifth Edition (© Garland Science 2008) Mitochondria and chloroplasts are unique among other organelles Mitochondria 1. Energy organelles 2. Are defined by a double-lipid bilayer/ double membrane (like the nucleus) 3. Have their own genome. 4. Have their own ribosomes and transfer RNAs to make proteins (like cells) 62
Figure 1-34 Molecular Biology of the Cell , Fifth Edition (© Garland Science 2008) Plausible Origin of Mitochondria Predation of oxidizing bacteria Became symbiotic: large cell provided protection and food molecules and bacteria oxidized food to release energy : in the form ATP Symbiotic relationship eventually became permanent by loss of redundant genomes 63
Figure 1-36 Molecular Biology of the Cell , Fifth Edition (© Garland Science 2008) Plausible Origin of Chloroplasts Predation of photosynthetic bacteria ( e.g cyanobacteria ) Became symbiotic: cyanobacteria converted sunlight to food while large eukaryotic cell with mitochondria oxidized food molecules to chemical energy Symbiotic relationship eventually became permanent by loss of redundant genomes 64
Stage 1 : Ancestral pre-eukaryotic cells were likely predatorial, eating other cells by phagocytosis.

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