Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Human Anatomy & Physiology, Sixth Edition Elaine N. Marieb PowerPoint ® Lecture Slides prepared by Vince Austin, University of Kentucky 3 Cells: The Living Units Part C

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Golgi Apparatus  Stacked and flattened membranous sacs  Functions in modification, concentration, and packaging of proteins  Transport vessels from the ER fuse with the cis face of the Golgi apparatus  Proteins then pass through the Golgi apparatus to the trans face  Secretory vesicles leave the trans face of the Golgi stack and move to designated parts of the cell

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Golgi Apparatus Figure 3.20a

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Role of the Golgi Apparatus Figure 3.21

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Lysosomes  Spherical membranous bags containing digestive enzymes  Digest ingested bacteria, viruses, and toxins  Degrade nonfunctional organelles  Breakdown glycogen and release thyroid hormone  Breakdown nonuseful tissue  Breakdown bone to release Ca 2+  Secretory lysosomes are found in white blood cells, immune cells, and melanocytes

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Endomembrane System  System of organelles that function to:  Produce, store, and export biological molecules  Degrade potentially harmful substances  System includes:  Nuclear envelope, smooth and rough ER, lysosomes, vacuoles, transport vesicles, Golgi apparatus, and the plasma membrane Endomembrane System PLAY

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Endomembrane System Figure 3.23

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Peroxisomes  Membranous sacs containing oxidases and catalases  Detoxify harmful or toxic substances  Neutralize dangerous free radicals  Free radicals – highly reactive chemicals with unpaired electrons (i.e., O 2 – )

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cytoskeleton  The “skeleton” of the cell  Dynamic, elaborate series of rods running through the cytosol  Consists of microtubules, microfilaments, and intermediate filaments

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cytoskeleton Figure 3.24

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Microtubules  Dynamic, hollow tubes made of the spherical protein tubulin  Determine the overall shape of the cell and distribution of organelles

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Microfilaments  Dynamic strands of the protein actin  Attached to the cytoplasmic side of the plasma membrane  Braces and strengthens the cell surface  Attach to CAMs and function in endocytosis and exocytosis

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Intermediate Filaments  Tough, insoluble protein fibers with high tensile strength  Resist pulling forces on the cell and help form desmosomes

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Motor Molecules  Protein complexes that function in motility  Powered by ATP  Attach to receptors on organelles

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Motor Molecules Figure 3.25a

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Motor Molecules Figure 3.25b

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Centrioles  Small barrel-shaped organelles located in the centrosome near the nucleus  Pinwheel array of nine triplets of microtubules  Organize mitotic spindle during mitosis  Form the bases of cilia and flagella

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Centrioles Figure 3.26a, b

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cilia  Whiplike, motile cellular extensions on exposed surfaces of certain cells  Move substances in one direction across cell surfaces Cilia and Flagella PLAY

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cilia Figure 3.27a

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cilia Figure 3.27b

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cilia Figure 3.27c

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Nucleus  Contains nuclear envelope, nucleoli, chromatin, and distinct compartments rich in specific protein sets  Gene-containing control center of the cell  Contains the genetic library with blueprints for nearly all cellular proteins  Dictates the kinds and amounts of proteins to be synthesized

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Nucleus Figure 3.28a

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Nuclear Envelope  Selectively permeable double membrane barrier containing pores  Encloses jellylike nucleoplasm, which contains essential solutes  Outer membrane is continuous with the rough ER and is studded with ribosomes  Inner membrane is lined with the nuclear lamina, which maintains the shape of the nucleus  Pore complex regulates transport of large molecules into and out of the nucleus

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Nucleoli  Dark-staining spherical bodies within the nucleus  Site of ribosome production

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Chromatin  Threadlike strands of DNA and histones  Arranged in fundamental units called nucleosomes  Form condensed, barlike bodies of chromosomes when the nucleus starts to divide Figure 3.29

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cell Cycle  Interphase  Growth (G 1 ), synthesis (S), growth (G 2 )  Mitotic phase  Mitosis and cytokinesis Figure 3.30

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Interphase  G 1 (gap 1) – metabolic activity and vigorous growth  G 0 – cells that permanently cease dividing  S (synthetic) – DNA replication  G 2 (gap 2) – preparation for division Late Interphase PLAY