How to Use This Presentation • To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show.” • To advance through the presentation, click the right-arrow key or the space bar. • From the resources slide, click on any resource to see a presentation for that resource. • From the Chapter menu screen click on any lesson to go directly to that lesson’s presentation. • You may exit the slide show at any time by pressing the Esc key. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Resources Chapter Presentation Transparencies Visual Concepts Standardized Test Prep Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Cell Structure Table of Contents Section 1 Looking at Cells Section 2 Cell Features Section 3 Cell Organelles Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Objectives • Describe how scientists measure the length of objects. • Relate magnification and resolution in the use of microscopes. • Analyze how light microscopes function. • Compare light microscopes with electron microscopes. • Describe the scanning tunneling microscope. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Cells Under the Microscope Measuring Cell Structures Measurements taken by scientists are expressed in metric units. The official name of the metric system is the International System of Measurements, abbreviated SI. The table below summarizes the SI units used to measure length. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Cells Under the Microscope, continued • Magnification is the quality of making an image appear larger than its actual size. • Resolution is a measure of the clarity of an image. Both high magnification and good resolution are needed to view the details of extremely small objects clearly. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Cells Under the Microscope, continued Electron microscopes have much higher magnifying and resolving powers than light microscopes. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Parts of a Light Microscope Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Types of Microscopes Light microscopes form an image when light passes through one or more lenses to produce an enlarged image of a specimen. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Magnification and Resolution Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Types of Microscopes, continued Electron Microscopes • Electron microscopes form an image of a specimen using a beam of electrons rather than light. • The electron beam and specimen must be in a vacuum so that the electron beam will not bounce off of gas molecules. • Live organisms cannot be viewed with an electron microscope. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Types of Microscopes, continued Transmission Electron Microscope • An electron beam is directed at a very thin slice of a specimen stained with metal ions. Some structures become more heavily stained than others. • The heavily stained parts absorb electrons, those that are lightly stained allow electrons to pass through. • The electrons that pass through strike a fluorescent screen, forming an image. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Types of Microscopes, continued Scanning Electron Microscope • An electron beam is focused on a specimen coated with a very thin layer of metal. • The electrons that bounce off the specimen form an image on a fluorescent screen. • The image shows three-dimensional details of the surface of a specimen. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Types of Microscopes, continued Scanning Tunneling Microscope • A needle-like probe measures differences in voltage caused by electrons that leak, or tunnel, from the surface of the object being viewed. • A computer tracks the movement of the probe across the surface of the object. • The image shows three-dimensional details of the surface of a specimen. • Live specimens and objects as small as atoms can be viewed. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 1 Looking at Cells Types of Microscopes Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Objectives • List the three parts of the cell theory. • Determine why cells must be relatively small. • Compare the structure of prokaryotic cells with that of eukaryotic cells. • Describe the structure of cell membranes. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features The Cell Theory The Cell Theory has three parts: 1. All living things are made of one or more cells. 2. Cells are the basic units of structure and function in organisms. 3. All cells arise from existing cells. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Cell Theory Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features The Cell Theory, continued Cell Size Small cells function more efficiently than large cells. If a cell’s surface area–to-volume ratio is too low, substances cannot enter and leave the cell well enough to meet the cell’s needs. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features The Cell Theory, continued Common Cell Features Cells share common structural features, including: • • • • • an outer boundary called the cell membrane, interior substance called cytoplasm, structural support called the cytoskeleton, genetic material in the form of DNA cellular structures that make proteins, called ribosomes Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Cytoplasm Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Prokaryotes Prokaryotes are single-celled organisms that lack a nucleus and other internal compartments. They have a cell wall, may have cilia or flagella, and have a single circular molecule of DNA. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Parts of a Prokaryotic Cell Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Structure of Cilia and Flagella Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Eukaryotic Cells Eukaryotic cells have: • A nucleus which contains the cell’s DNA • Other internal compartments called organelles. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Comparing Prokaryotes and Eukaryotes Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Parts of an Animal Cell Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Eukaryotic Cells, continued • The cytoskeleton provides the interior framework of a cell. There are three basic kinds of cytoskeletal fibers. 1. Microfilaments: long slender filaments made of the protein actin 2. Microtubules: hollow tubes made of the protein tubulin. 3. Intermediate fibers: thick ropes made of protein. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Eukaryotic Cells, continued The cytoskeleton’s network of protein fibers anchors the cell’s organelles and other components of the cytoplasm. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Cytoskeleton Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features The Cell Membrane • The cell membrane is a selectively permeable barrier that determines which substances enter and leave the cell. • The selective permeability of the cell is mainly caused by the way phospholipids interact with water. • A phospholipid is a lipid made of a phosphate group and two fatty acids. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features The Cell Membrane, continued Cell membranes are made of a double layer of phospholipids, called a bilayer. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features The Cell Membrane, continued Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Phospholipid Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Lipid Bilayer Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Cell Membrane Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 2 Cell Features Parts of the Cell Membrane Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Objectives • Describe the role of the nucleus in cell activities. • Analyze the role of internal membranes in protein production. • Summarize the importance of mitochondria in eukaryotic cells. • Identify three structure in plant cells that are absent from animal cells. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles The Nucleus • The nucleus is an internal compartment that houses the cell’s DNA. Most functions of a eukaryotic cell are controlled by the cell’s nucleus. • The nucleus is surrounded by a double membrane called the nuclear envelope. • Scattered over the surface of the nuclear envelope are many small channels called nuclear pores. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles The Nucleus, continued Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles The Nucleus, continued • Ribosomal proteins and RNA are made in the nucleus. • Ribosomes are partially assembled in a region of the nucleus called the nucleolus. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Nucleus of a Cell Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Ribosomes and the Endoplasmic Reticulum • Ribosomes are the cellular structures on which proteins are made. • The Endoplasmic Reticulum or ER is an extensive system of internal membranes that move proteins and other substances through the cell. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Ribosomes Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Ribosomes and the Endoplasmic Reticulum, continued • The part of the ER with attached ribosomes is called the rough ER. • The rough ER helps transport proteins that are made by the attached ribosomes. • New proteins enter the ER. • The portion of the ER that contains the completed protein pinches off to form a vesicle. • A vesicle is a small, membrane-bound sac that transports substances in cells. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Ribosomes and the Endoplasmic Reticulum, continued The ER moves proteins and other substances within eukaryotic cells. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Endoplasmic Reticulum (ER) and Ribosomes Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Ribosomes and the Endoplasmic Reticulum, continued Packaging and Distribution of Proteins • Vesicles that contain newly made proteins move through the cytoplasm from the ER to an organelle called the Golgi apparatus. • The Golgi apparatus is a set of flattened, membranebound sacs that serve as the packaging and distribution center of the cell. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Golgi Apparatus Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Ribosomes and the Endoplasmic Reticulum, continued Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Lysosome Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Mitochondria • Mitochondria are organelles that harvest energy from organic compounds to make ATP. • ATP is the main energy currency of cells. Most ATP is made inside the mitochondria. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Mitochondria, continued • Mitochondria have two membranes. The outer membrane is smooth. The inner membrane is greatly folded, and has a large surface area. • Mitochondria have their own DNA. Mitochondria reproduce independently of the cell. Mitochondrial DNA is similar to the DNA of prokaryotic cells. • Mitochondria are thought to be descendents of primitive prokaryotes. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Mitochondria, continued Mitochondria have an inner and an outer membrane. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Mitochondrion Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Structures of Plant Cells Plants have three unique structures that are not found in animal cells: • Cell Wall • Chloroplasts • Central Vacuole Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Parts of a Plant Cell Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Structures of Plant Cells, continued • The cell membrane of plant cells is surrounded by a thick cell wall, composed of proteins and carbohydrates. • The cell wall • helps support and maintain the shape of the cell • protects the cell from damage • connects the cell with adjacent cells Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Parts of a Cell Wall Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Structures of Plant Cells, continued • Chloroplasts are organelles that use light energy to make carbohydrates from carbon dioxide and water. • Chloroplasts, along with mitochondria, supply much of the energy needed to power the activities of plant cells. • Chloroplasts, like mitochondria, have their own DNA and reproduce independently of the plant cell. • Chloroplasts, like mitochondria, are thought to be descendents of ancient prokaryotes. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Chloroplasts Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Structures of Plant Cells, continued Central Vacuole: • Most of a plant cell’s volume is taken up by a large, membrane-bound space called the central vacuole. • The central vacuole stores water and may contain ions, nutrients, and wastes. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Vacuoles Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Comparing Plant and Animal Cells Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Section 3 Cell Organelles Summary of Organelles Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Standardized Test Prep Multiple Choice Use the figure below and your knowledge of science to answer questions 1–3. Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Standardized Test Prep Multiple Choice, continued 1. Which structures in this cell are also found in prokaryotic cells? A. B. C. D. A and B C and D E and F A and E Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Standardized Test Prep Multiple Choice, continued 1. Which structures in this cell are also found in prokaryotic cells? A. B. C. D. A and B C and D E and F A and E Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Standardized Test Prep Multiple Choice, continued 2. Which features of plant cells are missing from this cell? F. G. H. J. cell wall and chloroplasts Golgi apparatus and mitochondria rough ER and lysosomes smooth ER and nucleus Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Standardized Test Prep Multiple Choice, continued 2. Which features of plant cells are missing from this cell? F. G. H. J. cell wall and chloroplasts Golgi apparatus and mitochondria rough ER and lysosomes smooth ER and nucleus Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Standardized Test Prep Multiple Choice, continued 3. What is the function of the structure labeled A? A. B. C. D. making ATP making carbohydrates making proteins moving proteins through the cell Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Standardized Test Prep Multiple Choice, continued 3. What is the function of the structure labeled A? A. B. C. D. making ATP making carbohydrates making proteins moving proteins through the cell Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Metric Units of Length and Equivalents Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Object Size and Magnifying Power of Microscope Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Compound Light Microscope Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Surface Area–to-Volume Ratio Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Prokaryotic Cell Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Eukaryotic Cells Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 The Cell Membrane Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 The Cell Membrane Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Processing of Proteins Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Plant Cell Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Chapter 3 Organelles Chapter menu Resources Copyright © by Holt, Rinehart and Winston. All rights reserved.