Chapter 4 Powerpoint
Chapter 4 Powerpoint Bio 110
Popular in Biology 110
Popular in Science
This 58 page Class Notes was uploaded by Abigail Barajas on Thursday September 22, 2016. The Class Notes belongs to Bio 110 at Johnston Community College taught by Dr. Pamela Phillips in Fall 2016. Since its upload, it has received 2 views. For similar materials see Biology 110 in Science at Johnston Community College.
Reviews for Chapter 4 Powerpoint
Report this Material
What is Karma?
Karma is the currency of StudySoup.
Date Created: 09/22/16
Essentials of Biology Sylvia S. Mader Michael Windelspecht Chapter 4 Inside the Cell Lecture Outline Seall figures and tables pre-inserted into PowerPoint without notes. the animation to play, pause, and turn audio/text on or off. Please note: once you have used any of the animation functions (such as Play or Pause), you must first click in the white background before you advance the next slide. 4.1 Cells Under the Microscope • Cells Are extremely diverse Nearly all require a microscope to be seen Each type in our body is specialized for a particular function • Light microscope Invented in 17 century Limited by properties of light • Electron microscope Invented in 1930s Overcomes limitation by using beam of electrons Figure 4.1 Using microscopes to see cells. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. LM of Euglena Scientist using a light microscope. Scientist using an electron microscope. SEM of spiderling (TEM, lymphocyte): © Dr. Gopal Murti/Visuals Unlimited; (electron microscope): © Inga Spence/Visuals Unlimited; (light microscope): © Corbis Images/Jupiter Images RF; (Euglena): © Tom Adams/Visuals Unlimited; (SEM, spider): © Science Photo Library.Getty RF Figure 4.2 Relative sizes of some living things and their components. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 0.1 nm 1 nm 10 nm 100 nm 1 µm 10 µm 100 µm 1 mm 1 cm 0.1 m 1 m 10 m 100 m 1 km blue whale proteins chloroplast mouse plant and frog animal egg amino acids viruses cells atoms human egg most bacteria ant electron microscope light microscope human unaided eye • Why are cells so small? Need surface areas large enough for entry and exit of materials Surface-area-to-volume ratio Small cells have more surface area for exchange. Adaptations to increase surface area • Microvilli in the small intestine increase surface area for absorption of nutrients 4.2 The Plasma Membrane • Marks boundary between outside and inside of a cell • Regulates passage in and out of a cell • Phospholipid bilayer with embedded proteins Polar heads (hydrophilic) of phospholipids face into watery medium Nonpolar tails (hydrophobic) face each other • Fluid-mosaic model—the structure of the plasma membrane Figure 4.4 A model of the plasma membrane. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. polar head phospholipid carbohydrate chain nonpolar tail Outside of cell glycoprotein external membrane surface phospholipid bilayer hydrophilic hydrophobic internal membrane surface hydrophilic protein molecule cholesterol cytoskeleton filaments Inside of cell Figure 4.5a Membrane protein diversity. • Membrane Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. proteins Channel proteins • Form tunnel for specific molecules a. Channel protein Figure 4.5b Membrane Transport proteins protein diversity. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • Involved in passage of molecules through the membrane, sometimes requiring input of energy b. Transport protein Figure 4.5c Membrane Cell recognition protein diversity. proteins Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • Enable our body to distinguish between our own cells and cells of other organisms c. Cell recognition protein Figure 4.5d Membrane protein diversity. Receptor proteins Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • Allow signal molecules to bind, causing a cellular response d. Receptor protein Figure 4.5e Membrane protein diversity. Enzymatic Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. proteins • Directly participate in metabolic reactions e. Enzymatic protein Figure 4.5f Membrane protein diversity. Junction proteins Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • Form junctions between cells • Cell-to-cell adhesion and communication f. Junction proteins 4.3 The Two Main Types of Cells • Cell theory All organisms are composed of cells. All cells come only from preexisting cells. • All cells have: • A plasma membrane to regulate movement of material Cytoplasm where chemical reactions occur Genetic material for growth and reproduction • 2 main types of cells Based on organization of genetic material 1. Prokaryotic cells—lack membrane-bounded nucleus 2. Eukaryotic cells—have nucleus housing DNA • Prokaryotic cells Organisms from the domains Bacteria and Archaea Generally smaller and simpler in structure than eukaryotic cells • Allows them to reproduce very quickly and effectively Extremely successful group of organisms Bacteria • Well known because some cause disease • Others have roles in the environment • Some are used to manufacture chemicals, food, drugs, etc. • Bacterial structure Cytoplasm surrounded by plasma membrane and cell wall • Sometimes a capsule—protective layer • Plasma membrane is the same as eukaryotes Cell wall maintains the shape of a cell DNA—single circular, coiled chromosome located in nucleoid (region—not membrane enclosed) Ribosomes—site of protein synthesis Appendages • Flagella—propulsion • Fimbriae—attachment to surfaces • Conjugation pili—DNA transfer Figure 4.6 A prokaryotic cell. 4.4 Eukaryotic Cells • Protists, fungi, plants, and animals • Have a membrane-bounded nucleus housing DNA • Much larger than prokaryotic cells • Compartmentalized and contain organelles • 4 categories of organelles: 1. Nucleus and ribosomes 2. Endomembrane system 3. Energy-related 4. Cytoskeleton Organelles • http://www.enchantedlearning.com/subject s/plants/cell/ Mitochondria and Chloroplast • What do they have in common? DNA • Where located? Plants contain chloroplasts and mitochondria, animal cells only have mi.ochondria Figure 4.7 Structure of a typical animal cell. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. plasma membrane Lysosomes – involved in nuclear envelope breaking down material not nucleolus producing material in cell. chromatin endoplasmic Think of tadpole – tail is reticulum absorbed and voila, we have ×10,000 a frog! a. nucleus: nuclear envelope vesicle nuclear formation pore vesicle nucleolus centrioles chromatin (in centrosome) cytoskeleton: rough ER filaments microtubules mitochondrion polyribosome (in cytoplasm) ribosome ribosome (attached to rough ER) (in cytoplasm) smooth ER lysosome cytoplasm Golgi apparatus b. (a); © Dr. Dennis Kunkel/Visuals Unlimited Figure 4.8 Structure of a typical plant cell. Nucleus and ribosomes Nucleus • Stores genetic information • Chromatin—diffuse DNA, protein, some RNA Prior to cell division, DNA compacts into chromosomes • DNA organized into genes, which specify a polypeptide Relayed to ribosome using messenger RNA (mRNA) • Nucleolus—region where ribosomal RNA (rRNA) is made • Nuclear envelope—double membrane Nuclear pores permit passage in and out Figure 4.9 Structure of the nucleus. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. outer membrane nuclear envelope inner membrane nucleolus chromatin nuclear pores nucleoplasm ER lumen ribosome endoplasmic reticulum SEM of freeze-fractured nuclear envelope (right): Courtesy E.G. Pollock Ribosomes • Carry out protein synthesis in the cytoplasm • Found in both prokaryotes and eukaryotes • Composed of 2 subunits • Mix of proteins and ribosomal RNA (rRNA) • Receive mRNA as instructions sequence of amino acids in a polypeptide • In eukaryotes, Some ribosomes free in cytoplasm Many attached to endoplasmic reticulum If ribosomes are not functioning – then proteins are not produced. Figure 4.10 The nucleus, ribosomes, and endoplasmic reticulum (ER). Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Nucleus Cytoplasm 4 At termination, the polypeptide becomes a protein. The ribosomal subunits disengage, DNA and the mRNA is released. small mRNA subunit nuclear pore 2 In the cytoplasm, the 3 If a ribosome attaches large subunit mRNA and ribosomal to a receptor on the ER, subunits join, and the polypeptide enters the lumen of the ER. polypeptide synthesis 1 mRNA is produced in begins. ribosome the nucleus but moves through a nuclear pore protein into the cytoplasm. ribosome polypeptide receptor lumen of the ER ribosome ER membrane Endoplasmic reticulum Endomembrane system Consists of nuclear envelope, membranes of endoplasmic reticulum, Golgi apparatus, and numerous vesicles Helps compartmentalize cell • Restricts certain reactions to specific regions Transport vesicles carry molecules from one part of the system to another. • Endoplasmic reticulum Complicated system of membranous channels and saccules Physically continuous with outer membrane of nuclear envelope Rough ER • Studded with ribosomes • Modifies proteins in lumen • Forms transport vesicles going to Golgi apparatus Smooth ER • Continuous with rough ER • No ribosomes • Synthesizes lipids like phospholipids and steroids • Function depends on cell Produces testosterone, detoxifies drugs Figure 4.11 Endoplasmic reticulum (ER). Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. nuclear envelope ribosomes rough ER smooth ER © R. Bolender and D. Fawcett/Visuals Unlimited • Golgi apparatus Stack of flattened saccules Transfer station Receives vesicles from ER Modifies molecules within the vesicles Sorts and repackages for new destination • Some are lysosomes • Lysosomes Vesicles that digest molecules or portions of the cell Digestive enzymes Tay-Sachs disease Figure 4.12 Endomembrane system. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. rough ER smooth ER synthesizes proteins synthesizes lipids and and packages them in performs other functions. vesicles. transport vesicles transport vesicles from rough ER from smooth ER Golgi apparatus modifies lipids and proteins; sorts them and packages them in lysosomes vesicles. digest molecules or old cell parts. secretory vesicles fuses with the plasma membrane as secretion occurs. incoming vesicles bring substances into the cell. Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer. • Vacuoles Membranous sacs Larger than vesicles Rid a cell of excess water Digestion Storage • Plant pigments • Animal adipocytes Figure 4.13 Vacuoles. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. vacuoles c. ×400 a. ×800 b. ×7,700 a: © Roland/Birke/Peter Arnold/Photolibrary; b: © Newcomb/Wergin/Biological Photo Service; c: © The McGraw Hill Companies, Inc./Al Telser, photographer Energy-related organelles Chloroplasts • Use solar energy to synthesize carbohydrates through the process of photosynthesis • Plants and algae • Three-membrane system Double membrane enclosing stroma • Thylakoids formed from third membrane Thylakoid membrane contains pigments that capture solar energy • Chloroplasts have their own DNA and ribosomes. Figure 4.14a Chloroplast structure. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. a. a: © Dr. George Chapman/Visuals Unlimited Figure 4.14a Chloroplast structure. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. outer membrane double membrane inner membrane granum stroma thylakoid thylakoid a. space membrane thylakoid Mitochondria • Found in BOTH plants and animals • Usually only visible under an electron microscope • Bounded by double membrane • Break down carbohydrates to produce adenosine triphosphate (ATP) • Cellular respiration—needs oxygen, produces carbon dioxide • Inner membrane folds called cristae Increase surface area • Inner membrane encloses matrix Mixture of enzymes assisting in carbohydrate breakdown Reactions permit ATP synthesis • Matrix also contains its own DNA and ribosomes Figure 4.15 Mitochondrion structure. Greater surface area means greater ATP production.r Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. outer membrane double inner membrane membrane matrix cristae a. b. ×70,000 b: Courtesy Keith Porter The cytoskeleton and motor proteins Cytoskeleton—network of interconnected protein filaments and tubules Extends from the nucleus to the plasma membrane Only in eukaryotes Maintains cell shape Motor proteins—allow cell and organelles to move • Myosin, kinesin, and dynein • Motor proteins Instrumental in allowing cellular movements Myosin https://youtu.be/0kFmbrRJq4w • Interacts with actin • Cells move in amoeboid fashion • Muscle contraction Kinesin and dynein https://youtu.be/gbycQf1TbM0 • Move along microtubules • Transport vesicles from Golgi apparatus to final destination Figure 4.16b Motor proteins. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. vesicle kinesin ATP receptor kinesin microtubule vesicle moves, not microtubule b. Kinesin • Microtubules Small, hollow cylinders Assembly controlled by centrosome Help maintain cell shape and act as track for organelles and other materials to move • Intermediate filaments Intermediate in size Ropelike assembly Run from nuclear envelope to plasma membrane Figure 4.17 Microtubules. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. microtubule cell centrosome nucleus Figure 4.18 Actin filaments. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. microvilli actin filaments cell nucleus • Actin filaments 2 chains of monomers twisted in a helix Forms a dense web to support the cell Centrosome • What is a Centrosome? • Centrosomes are organelles (membrane bound) that are found inside of cells. They are only found inside of eukaryotic cells, or those cells with a nucleus and membrane-bound organelles. Centrosomes are comprised of two centrioles that are essentially just rings of microtubules. • What is its Purpose? • The purpose of the centrosome is to help organize microtubules (hollow tubes of protein, similar looking to microscopic hollow spaghetti) to be utilized during cell division. It also works to use the microtubules to create part of the cytoskeleton of the cell. This helps give the cell its structure. In a sense, the centrosome helps to stabilize the structure of the cell. While these might seem like simplistic tasks, they are extremely important and critical roles. • **Plant cells have centrosomes but not centrioles. Organelles in animal cells are moved by microtubules for the most part, organelles in plant cells move due to cytoplasmic streaming. • Centrioles Made of 9 sets of microtubule triplets Two centrioles lie at right angles. In animal cells, not present in plant cells Figure 4.19 Centrioles. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. one microtubule triplet centrosome one pair of centrioles in a centrosome (Left); © Don W. Fawcett/Photo Researchers, Inc • Cilia and flagella Eukaryotes For movement of the cell or fluids past the cell Similar construction in both • 9+2 pattern of microtubules Cilia shorter and more numerous than flagella Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 4.20 Cilia and flagella. cilia in bronchial wall of lungs flagella of sperm a. Flagellum Flagellum cross section central microtubules microtubule doublet dynein side arms TEM ×350,000 plasma membrane Basal body b. cross section a; (cilia): © Manfred Kage/Peter Arnold/Photolibrary; a(sperm): © David M. Phillips/Photo Researchers, Inc.; b (both): © William L. Dentler/Biological Photo Service 4.5 Outside the Eukaryotic Cell • Plant cell walls Primary cell walls • Cellulose fibrils and noncellulose substances • Wall stretches when cell is growing Secondary cell walls (some plant cells) • Forms inside primary cell wall • Woody plants • Lignin adds strength Plasmodesmata • Plant cells connected by numerous channels that pass through cell walls • For exchange of water and small solutes between cells Figure 4.21 Plasmodesmata. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. cell wall plasmodesmata cell wall middle lamella plasma membrane Cell 1 Cell 2 cytoplasm cytoplasm plasmodesmata cell wall ×53,000 (Bottom): © E.H. Newcomb/Biological Photo Service • Exterior cell surfaces in animals No cell wall Extracellular matrix (ECM) • Meshwork of fibrous proteins and polysaccharides • Collagen and elastin well-known proteins • Matrix varies—flexible in cartilage, hard in bone • Enables cells to migrate along intracellular fibers • Permit communication between the extracellular matrix and the cells • Helps cells have flexibility Figure 4.22 Animal cell extracellular matrix. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. elastic fiber collagen polysaccharide receptor protein plasma membrane cytoskeleton filament cytoplasm • Junctions between cells Adhesion junctions • Internal cytoplasmic plaques joined by intercellular filaments • Sturdy but flexible sheet of cells Figure 4.23a Junctions between cells of the intestinal wall. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 4.23b Junctions between cells of the intestinal wall. Tight junctions Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • Plasma membrane proteins attach to each other • Zipper-like • Cells of tissues that serve as barriers plasma membranes tight junction proteins intercellular space Tight junction Figure 4.23c Junctions between Gap junctions cells of the intestinal wall. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • Allow cells to communicate through plasma membrane channels plasma • Lend strength while allowing membranes small molecules and ions to pass through membrane channel intercellular space Gap junction