Cell Structure Chapter 4 Cells are active Cells are active http youtu be MgVPLNu S w Prokaryotic vs Eukaryotic Cells Domain Cell Type Bacteria Prokaryotic Archaea Prokaryotic Eukarya Eukaryotic Common to all cells Surrounded by plasma membrane DNA Chromosomes organized into genes Ribosomes synthesize proteins Eukaryotic cells Prokaryotic cells Genetic material enclosed in nucleus Have no nucleus Are generally small Many membrane bound compartments organelles Prokaryotes are unicellular Generally larger Spectacularly diverse Eukaryotes can be unicellular or multicellular Transmission electron micrograph TEM Cells Size range of cells 4 2 Measurements 1 centimeter cm 10 2 meter m 0 4 inch 1 millimeter mm 10 3 m 1 micrometer m 10 3 mm 10 6 m 1 nanometer nm 10 3 m 10 9 m Cells are small Cell size is constrained by surface to volume ratio http hilem001 wikispaces com Surface Area and Volume Surface to volume ratio Microvilli Intestinal epithelial cell specialized for nutrient absorption Plasma membrane Microfilaments actin filaments Intermediate filaments 0 25 m Prokaryotic cell structure 4 3 4 4 Cytoplasm Ribosomes protein synthesis Nucleoid DNA and protein Plasma membrane Cell wall polysaccharide Capsule slime layer polysaccharide Pili attachment DNA exchange Flagellum locomotion A typical rod shaped bacterium Photosynthetic bacterium Eukaryotic cell structure 4 6 4 7 Eukaryotic cells are complex Nucleus Cytoplasm Cytosol Plasma membrane Animal cell Plant cell Cytoplasm everything between plasma membrane and nucleus Cytosol fluid matrix in which all of the components of the cytoplasm reside Know similarities and differences between eukaryotic cells and prokaryotic cells Know similarities and differences between plant and animal cells Animal vs Plant Cells Cell wall Eukaryotic cell structure and function selected lecture topics READ ENTIRE CHAPTER Mitochondria and Chloroplasts Endosymbiosis Nucleus Ribosomes Endomembrane system Cytoskeleton Motor Proteins Mitochondria and chloroplasts function in the production of energy rich molecules that the cell can use for all its other energy requiring activities share a similar evolutionary history Endosymbiosis Mitochondria and chloroplasts Both arose from free living bacteria by endosymbiosis bear signatures of bacterial ancestry Contain their own DNA Most genes originally present in the bacterial endosymbionts were transferred to the nuclear genome or lost Organelle genomes still encode a few proteins but not many mitochondria 13 chloroplasts 70 120 Contain their own ribosomes to synthesize proteins encoded in their own genomes 2 000 3 000 proteins required for mitochondria chloroplast function most are coded for by genes in the nuclear genome synthesized on ribosomes in the cytosol and transported into the organelle after synthesis Divide separately from the cell Structure of mitochondria 4 16 Mitochondria are found in nearly all eukaryotic cells plants too produce most of the ATP needed for cellular activities via respiration Matrix Intermembrane space DNA Inner membrane folded in cristae Ribosome Outer membrane 0 2 m Mitochondria also function in Programmed cell death apoptosis Normal development Destruction of damaged cells Abnormal mitochondrial function implicated in neuromuscular diseases Structure of chloroplasts 4 17 Chloroplasts green plastids that carry out photosynthesis present in green tissues of plants and algae Outer membrane Inner membrane Thylakoid membranes DNA 1 5 m Ribosome Chloroplasts and non green plastids also function in synthesis of Starch Some amino acids Membrane lipids and oils seed oils source of biodiesel Carotenoids red yellow pigment vitamin A precursor Vitamins E and C Products of plastids are essential in the human diet are key targets of plant breeding and biotechnology and are essential for all plant cells