1.26k likes | 1.44k Views
Table of Contents – pages iv-v. Unit 1: What is Biology? Unit 2: Ecology Unit 3: The Life of a Cell Unit 4: Genetics Unit 5: Change Through Time Unit 6: Viruses, Bacteria, Protists, and Fungi Unit 7: Plants Unit 8: Invertebrates Unit 9: Vertebrates Unit 10: The Human Body.
E N D
Table of Contents – pages iv-v Unit 1:What is Biology? Unit 2:Ecology Unit 3:The Life of a Cell Unit 4:Genetics Unit 5:Change Through Time Unit 6:Viruses, Bacteria, Protists, and Fungi Unit 7:Plants Unit 8:Invertebrates Unit 9:Vertebrates Unit 10:The Human Body
Table of Contents – pages iv-v Unit 1: What is Biology? Chapter 1:Biology: The Study of Life Unit 2: Ecology Chapter 2:Principles of Ecology Chapter 3:Communities and Biomes Chapter 4:Population Biology Chapter 5:Biological Diversity and Conservation Unit 3:The Life of a Cell Chapter 6:The Chemistry of Life Chapter 7:A View of the Cell Chapter 8:Cellular Transport and the Cell Cycle Chapter 9:Energy in a Cell
Unit 4: Genetics Chapter 10:Mendel and Meiosis Chapter 11:DNA and Genes Chapter 12:Patterns of Heredity and Human Genetics Chapter 13:Genetic Technology Unit 5: Change Through Time Chapter 14:The History of Life Chapter 15:The Theory of Evolution Chapter 16:Primate Evolution Chapter 17:Organizing Life’s Diversity Table of Contents – pages iv-v
Unit 6: Viruses, Bacteria, Protists, and Fungi Chapter 18:Viruses and Bacteria Chapter 19:Protists Chapter 20:Fungi Unit 7: Plants Chapter 21:What Is a Plant? Chapter 22:The Diversity of Plants Chapter 23:Plant Structure and Function Chapter 24:Reproduction in Plants Table of Contents – pages iv-v
Table of Contents – pages iv-v Unit 8: Invertebrates Chapter 25:What Is an Animal? Chapter 26:Sponges, Cnidarians, Flatworms, and Roundworms Chapter 27:Mollusks and Segmented Worms Chapter 28:Arthropods Chapter 29:Echinoderms and Invertebrate Chordates
Table of Contents – pages iv-v Unit 9: Vertebrates Chapter 30:Fishes and Amphibians Chapter 31:Reptiles and Birds Chapter 32:Mammals Chapter 33:Animal Behavior Unit 10: The Human Body Chapter 34:Protection, Support, and Locomotion Chapter 35:The Digestive and Endocrine Systems Chapter 36:The Nervous System Chapter 37:Respiration, Circulation, and Excretion Chapter 38:Reproduction and Development Chapter 39:Immunity from Disease
Unit Overview – pages 138-139 The Life of a Cell The Chemistry of Life A View of the Cell Cellular Transport and the Cell Cycle Energy in a Cell
Chapter Contents – page viii Chapter 8Cellular Transport and the Cell Cycle 8.1:Cellular Transport 8.1:Section Check 8.2:Cell Growth and Reproduction 8.2:Section Check 8.3:Control of the Cell Cycle 8.3:Section Check Chapter 8Summary Chapter 8Assessment
Chapter Intro-page 194 What You’ll Learn You will discover how molecules are transported across the plasma membrane. You will sequence the stages of cell division. You will identify the relationship between the cell cycle and cancer.
8.1 Section Objectives – page 195 Section Objectives: • Explain how the processes of diffusion, passive transport, and active transport occur and why they are important to cells. • Predict the effect of a hypotonic, hypertonic, or isotonic solution on a cell.
Section 8.1 Summary – pages 195 - 200 Osmosis: Diffusion of Water • Diffusion is the movement of particles from an area of higher concentration to an area of lower concentration. • In a cell, water always moves to reach an equal concentration on both sides of the membrane.
Section 8.1 Summary – pages 195 - 200 Osmosis: Diffusion of Water • The diffusion of water across a selectively permeable membrane is called osmosis. • Regulating the water flow through the plasma membrane is an important factor in maintaining homeostasis within a cell.
Section 8.1 Summary – pages 195 - 200 What controls osmosis? • Unequal distribution of particles, called a concentration gradient, is one factor that controls osmosis. Before Osmosis After Osmosis Water molecule Sugar molecule Selectively permeable membrane
Section 8.1 Summary – pages 195 - 200 Cells in an isotonic solution • Most cells whether in multicellular or unicellular organisms, are subject to osmosis because they are surrounded by water solutions. H2O H2O Water Molecule Dissolved Molecule
Section 8.1 Summary – pages 195 - 200 Cells in an isotonic solution • In an isotonic solution, the concentration of dissolved substances in the solution is the same as the concentration of dissolved substances inside the cell. H2O H2O Water Molecule Dissolved Molecule
Section 8.1 Summary – pages 195 - 200 Cells in an isotonic solution • In an isotonic solution, water molecules move into and out of the cell at the same rate, and cells retain their normal shape. H2O H2O Water Molecule Dissolved Molecule
Section 8.1 Summary – pages 195 - 200 Cells in an isotonic solution • A plant cell has its normal shape and pressure in an isotonic solution.
Section 8.1 Summary – pages 195 - 200 Cells in a hypotonic solution • In a hypotonic solution, water enters a cell by osmosis, causing the cell to swell. H2O H2O Water Molecule Dissolved Molecule
Section 8.1 Summary – pages 195 - 200 Cells in a hypotonic solution • Plant cells swell beyond their normal size as pressure increases.
Section 8.1 Summary – pages 195 - 200 Cells in a hypertonic solution • In a hypertonic solution, water leaves a cell by osmosis, causing the cell to shrink. H2O H2O Water Molecule Dissolved Molecule
Section 8.1 Summary – pages 195 - 200 Cells in a hypertonic solution • Plant cells lose pressure as the plasma membrane shrinks away from the cell wall.
Section 8.1 Summary – pages 195 - 200 Passive Transport • When a cell uses no energy to move particles across a membrane passive transport occurs. Concentration gradient Plasma membrane
Section 8.1 Summary – pages 195 - 200 Passive Transport by proteins • Passive transport of materials across the membrane using transport proteins is called facilitated diffusion. Channel proteins Concentration gradient Plasma membrane
Section 8.1 Summary – pages 195 - 200 Passive Transport by proteins • Some transport proteins, called channel proteins, form channels that allow specific molecules to flow through. Channel proteins Concentration gradient Plasma membrane
Section 8.1 Summary – pages 195 - 200 Passive transport by proteins • The movement is with the concentration gradient, and requires no energy input from the cell. Carrier proteins Concentration gradient Plasma membrane Step 1 Step 2
Section 8.1 Summary – pages 195 - 200 Passive transport by proteins • Carrier proteins change shape to allow a substance to pass through the plasma membrane. Carrier proteins Concentration gradient Plasma membrane Step 1 Step 2
Section 8.1 Summary – pages 195 - 200 Passive transport by proteins • In facilitated diffusion by carrier protein, the movement is with the concentration gradient and requires no energy input from the cell. Carrier proteins Concentration gradient Plasma membrane Step 1 Step 2
Section 8.1 Summary – pages 195 - 200 Active Transport • Movement of materials through a membrane against a concentration gradient is called active transport and requires energy from the cell. Carrier proteins Concentration gradient Plasma membrane Cellular energy Step 1 Step 2
Section 8.1 Summary – pages 195 - 200 How active transport occurs • In active transport, a transport protein called a carrier protein first binds with a particle of the substance to be transported. Carrier proteins Concentration gradient Plasma membrane Cellular energy Step 1 Step 2
Section 8.1 Summary – pages 195 - 200 How active transport occurs Click image to view movie.
Section 8.1 Summary – pages 195 - 200 How active transport occurs • Each type of carrier protein has a shape that fits a specific molecule or ion. Carrier proteins Concentration gradient Plasma membrane Cellular energy Step 1 Step 2
Section 8.1 Summary – pages 195 - 200 How active transport occurs • When the proper molecule binds with the protein, chemical energy allows the cell to change the shape of the carrier protein so that the particle to be moved is released on the other side of the membrane. Carrier proteins Concentration gradient Plasma membrane Cellular energy Step 1 Step 2
Section 8.1 Summary – pages 195 - 200 How active transport occurs • Once the particle is released, the protein’s original shape is restored. • Active transport allows particle movement into or out of a cell against a concentration gradient. Carrier proteins Concentration gradient Plasma membrane Cellular energy Step 1 Step 2
Section 8.1 Summary – pages 195 - 200 How active transport occurs Click image to view movie.
Section 8.1 Summary – pages 195 - 200 Transport of Large Particles • Endocytosis is a process by which a cell surrounds and takes in material from its environment. Nucleus Wastes Digestion Exocytosis Endocytosis
Section 8.1 Summary – pages 195 - 200 Transport of Large Particles • The material is engulfed and enclosed by a portion of the cell’s plasma membrane. Nucleus Wastes Digestion Endocytosis Exocytosis
Section 8.1 Summary – pages 195 - 200 Transport of Large Particles • The resulting vacuole with its contents moves to the inside of the cell. Nucleus Wastes Digestion Endocytosis Exocytosis
Section 8.1 Summary – pages 195 - 200 Transport of Large Particles • Exocytosis is the expulsion or secretion of materials from a cell. Nucleus Wastes Digestion Exocytosis Endocytosis
Section 8.1 Summary – pages 195 - 200 Transport of Large Particles • Endocytosis and exocytosis both move masses of material and both require energy. Nucleus Wastes Digestion Endocytosis Exocytosis
Section 1 Check Question 1 The diffusion of water across a selectively permeable membrane is called __________. (TX Obj 2; 4B) Water molecule Selectively permeable membrane Sugar molecule A. active transport B. endocytosis
Section 1 Check Question 1 The diffusion of water across a selectively permeable membrane is called __________. (TX Obj 2; 4B) Water molecule Selectively permeable membrane Sugar molecule C. exocytosis D. osmosis
Section 1 Check The answer is D, osmosis. Regulating the water flow through the plasma membrane is an important factor in maintaining homeostasis within the cell. Before osmosis After osmosis Water molecule Selectively permeable membrane Sugar molecule
Section 1 Check Question 2 What is the expected result of having an animal cell in a hypertonic solution? (TX Obj 2; 4B) A. The cell shrivels up. B. The plasma membrane shrinks away from the cell wall. C. The cell swells up. D. The cell retains its normal shape.
Section 1 Check The answer is A. In a hypertonic solution, cells experience osmosis of water out of the cell. Animal cells shrivel because of decreased pressure in the cells. H2O H2O Water molecule Sugar molecule
Section 1 Check Question 3 A grocer mists the celery display with water to keep it looking fresh. What type of solution is the celery now in? (TX Obj 2; 4B) A. isotonic B. hypotonic C. hypertonic D. exotonic
Section 1 Check The answer is B. Plant cells contain a rigid cell wall and do not burst even in a hypotonic solution.
Section 1 Check Question 4 Transport of materials across the plasma membrane that does not require energy from the cell but does use transport proteins is called __________. (TX Obj 2; 4B) Channel proteins A. osmosis Concentration gradient Plasma membrane B. simple diffusion
Section 1 Check Question 4 Transport of materials across the plasma membrane that does not require energy from the cell but does use transport proteins is called __________. (TX Obj 2; 4B) Channel proteins C. facilitated diffusion Concentration gradient Plasma membrane D. active transport
Section 1 Check The answer is C. Facilitated diffusion is a type of passive transport and requires no energy from the cell. Channel proteins Concentration gradient Plasma membrane