biosynthesis of lipid and proteins Golgi apparatus processing of proteins and

Biosynthesis of lipid and proteins golgi apparatus

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: biosynthesis of lipid and proteins •Golgi apparatus : processing of proteins and lipids, soring to different parts of cell (ship the stuff into different parts of the cell like shipment of online ordering) •Peroxisomes : redox reactions
Endosomes: membrane compartments undergoing exchange with plasma membrane and cell exterior Lysosomes: “stomach of the cell” breakdown complex macromolecules Mitochondria: oxidation of energy-rich molecules to make ATP(oxidative phosphorylation or respiration ) Chloroplasts: found in plants ,algae- use sunlight to make organic molecules Membrane-bound organelles (2) 41
How did eukaryotic cells evolve? 42
43 Figure 12-4a 4 th edition, Molecular Biology of the Cell (© Garland Science 2008) EVOLUTION OF THE NUCLEUS
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 44 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 45 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
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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 membrane____ (like the nucleus) 3. Have their own genome. 4. Have their own __Ribosomes__ and transfer RNAs to make proteins (like cells) 47
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:_ATP_ Symbiotic relationship eventually became permanent by loss of redundant genomes 48
Figure 1-36 Molecular Biology of the Cell , Fifth Edition (© Garland Science 2008) Plausible Origin of Chloroplasts Predation of photosynthetic bacteria (__ photosynthetic bacterium _) 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 49
Stage 1 : Ancestral pre-eukaryotic cells were likely predatorial, eating other cells by phagocytosis. Evolved the nucleus to protect DNA molecules from damage Membrane involution increased surface area to sustain cell size increase Stage 2: Predation of oxidizing bacteria lead to endosymbiosis and eventually mitochondria.

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