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

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 Table of Contents – pages iv-v

Table of Contents – pages iv-v 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

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

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 Table of Contents – pages iv-v

The Life of a Cell The Chemistry of Life A View of the Cell Cellular Transport and the Cell Cycle Energy in a Cell Unit Overview – pages 138-139

Chapter Contents – page viii Chapter 7 A View of a Cell 7.1: The Discovery of Cells 7.1: Section Check 7.2: The Plasma Membrane 7.2: Section Check 7.3: Eukaryotic Cell Structure 7.3: Section Check Chapter 7 Summary Chapter 7 Assessment Chapter Contents – page viii

You will identify the parts of prokaryotic and eukaryotic cells. What You’ll Learn You will identify the parts of prokaryotic and eukaryotic cells. You will identify the structure and function of the plasma membrane. You will relate the structure of cell parts to their functions. Chapter Intro-page 170

What You’ll Learn Cells are the foundation for the development of all life forms. Birth, growth, death, and all life functions begin as cellular functions. Chapter Intro-page 170

Endoplasmic Reticulum Lysosomes Nucleus Plasma Membrane Endoplasmic Reticulum Mitochondrion Chapter Intro-page 174

7.1 Section Objectives – page 171 Relate advances in microscope technology to discoveries about cells and cell structure. Compare the operation of a microscope with that of an electron microscope. Identify the main ideas of the cell theory. 7.1 Section Objectives – page 171

Section 7.1 Summary – pages 171-174 The History of the Cell Theory Before microscopes were invented, people believed that diseases were caused by curses and supernatural spirits. As scientists began using microscopes, they quickly realized they were entering a new world–one of microorganisms. Microscopes enabled scientists to view and study cells, the basic units of living organisms. Section 7.1 Summary – pages 171-174

Section 7.1 Summary – pages 171-174 Development of Light Microscopes The first person to record looking at water under a microscope was Anton van Leeuwenhoek. The microscope van Leeuwenhoek used is considered a simple light microscope because it contained one lens and used natural light to view objects. Section 7.1 Summary – pages 171-174

Section 7.1 Summary – pages 171-174 Development of Light Microscopes Compound light microscopes use a series of lenses to magnify objects in steps. These microscopes can magnify objects up to 1 500 times. Section 7.1 Summary – pages 171-174

Section 7.1 Summary – pages 171-174 Microscope Lab Techniques Click image to view movie. Section 7.1 Summary – pages 171-174

Section 7.1 Summary – pages 171-174 The Cell Theory Robert Hooke was an English scientist who lived at the same time as van Leeuwenhock. Hooke used a compound light microscope to study cork, the dead cells of oak bark. Cells are the basic building blocks of all living things. Section 7.1 Summary – pages 171-174

Section 7.1 Summary – pages 171-174 The cell theory is made up of three main ideas: All organisms are composed of one or more cells. The cell is the basic unit of organization of organisms. All cells come from preexisting cells. Section 7.1 Summary – pages 171-174

Section 7.1 Summary – pages 171-174 Development of Electron Microscopes The electron microscope was invented in the 1940s. This microscope uses a beam of electrons to magnify structures up to 500 000 times their actual size. Section 7.1 Summary – pages 171-174

Section 7.1 Summary – pages 171-174 Development of Electron Microscopes There are two basic types of electron microscopes. The scanning electron microscope scans the surface of cells to learn their three dimensional shape. The transmission electron microscope allows scientists to study the structures contained within a cell. Section 7.1 Summary – pages 171-174

Section 7.1 Summary – pages 171-174 Two Basic Cell Types Cells that do not contain internal membrane-bound structures are called prokaryotic cells. Click here The cells of most unicellular organisms such as bacteria do not have membrane bound structures and are therefore called prokaryotes. Section 7.1 Summary – pages 171-174

Section 7.1 Summary – pages 171-174 Two Basic Cell Types Cells containing membrane-bound structures are called eukaryotic cells. Click here Most of the multi-cellular plants and animals we know are made up of cells containing membrane-bound structures and are therefore called eukaryotes. Section 7.1 Summary – pages 171-174

Section 7.1 Summary – pages 171-174 Two Basic Cell Types The membrane-bound structures within eukaryotic cells are called organelles. Each organelle has a specific function that contributes to cell survival. Section 7.1 Summary – pages 171-174

Section 7.1 Summary – pages 171-174 Two Basic Cell Types Separation of organelles into distinct compartments benefits the eukaryotic cells. The nucleus is the central membrane-bound organelle that manages cellular functions. Section 7.1 Summary – pages 171-174

Question 1 How did the invention of the microscope impact society's understanding of disease? A. Scientists were able to view microorganisms that were previously unknown. B. Microscopes were invented after the development of the cell theory. Section 1 Check

Question 1 How did the invention of the microscope impact society's understanding of disease? C. It was once believed that viruses, not bacteria, caused diseases. D. Scientists could view membrane-bound organelles of prokaryotes. Section 1 Check

The answer is A. Before microscopes were invented, people believed that curses and supernatural spirits caused diseases. Microscopes enabled scientists to view cells, which led to the discovery that microorganisms cause some diseases. Section 1 Check

Question 2 Which of the following uses a beam of light and a series of lenses to magnify objects in steps? A. compound light microscope B. scanning electron microscope C. transmission electron microscope D. simple light microscope NC: 1.02 Section 1 Check

The answer is A. Most microscopes use at least two convex lenses The answer is A. Most microscopes use at least two convex lenses. Compound light microscopes use a light beam and a series of lenses and can magnify objects up to about 1500 times. Electron microscopes use a beam of electrons and can magnify structures up to 500 000 times. NC: 1.02 Section 1 Check

Question 3 What makes this cell eukaryotic? A. Because it has a cell wall. Nucleus Nucleolus Chromosomes B. Because it contains DNA. Organelles Plasma membrane NC: 2.02 Section 1 Check

Question 3 What makes this cell eukaryotic? C. Because it has membrane-bound organelles. Nucleus Nucleolus Chromosomes D. Because it does not have DNA. Organelles Plasma membrane NC: 2.02 Section 1 Check

Question 3 The Answer is C. Eukaryotic cells contain membrane-bound organelles that have specific functions in the cell; prokaryotic cells do not. Nucleus Nucleolus Chromosomes Organelles Plasma membrane NC: 2.02 Section 1 Check

Section 2 Objectives – page 175 Explain how a cell’s plasma membrane functions. Relate the function of the plasma membrane to the fluid mosaic model. Section 2 Objectives – page 175

Summary Section 2 – pages 175-178 All living cells must maintain a balance regardless of internal and external conditions. Survival depends on the cell’s ability to maintain the proper conditions within itself. Summary Section 2 – pages 175-178

Summary Section 2 – pages 175-178 Why cells must control materials The plasma membrane is the boundary between the cell and its environment. Summary Section 2 – pages 175-178

Summary Section 2 – pages 175-178 It is the plasma membrane’s job to: allow a steady supply of glucose, amino acids, and lipids to come into the cell no matter what the external conditions are. remove excess amounts of these nutrients when levels get so high that they are harmful. allow waste and other products to leave the cell. Summary Section 2 – pages 175-178

Summary Section 2 – pages 175-178 This process of maintaining the cell’s environment is called homeostasis. Selective permeability is a process used to maintain homeostasis in which the plasma membrane allows some molecules into the cell while keeping others out. Summary Section 2 – pages 175-178

Summary Section 2 – pages 175-178 Plasma Membrane Water Summary Section 2 – pages 175-178

Summary Section 2 – pages 175-178 Structure of the Plasma Membrane The plasma membrane is composed of two layers of phospholipids back-to-back. Phospholipids are lipids with a phosphate attached to them. Summary Section 2 – pages 175-178

Summary Section 2 – pages 175-178 Phosphate Group The lipids in a plasma membrane have a glycerol backbone, two fatty acid chains, and a phosphate group. Glycerol Backbone Two Fatty Acid Chains Summary Section 2 – pages 175-178

Summary Section 2 – pages 175-178 Makeup of the phospholipid bilayer The phosphate group is critical for the formation and function of the plasma membrane. Phosphate Group Summary Section 2 – pages 175-178

Summary Section 2 – pages 175-178 Makeup of the phospholipid bilayer The fluid mosaic model describes the plasma membrane as a flexible boundary of a cell. The phospholipids move within the membrane. Summary Section 2 – pages 175-178

Summary Section 2 – pages 175-178 Other components of the plasma membrane: Cholesterol plays the important role of preventing the fatty acid chains of the phospholipids from sticking together. Cholesterol Molecule Summary Section 2 – pages 175-178

Summary Section 2 – pages 175-178 Other components of the plasma membrane: Transport proteins allow needed substances or waste materials to move through the plasma membrane. Click image to view movie. Summary Section 2 – pages 175-178

Question 1 Which of the following best describes the plasma membrane's mechanism in maintaining homeostasis? A. protein synthesis B. selective permeability C. fluid composition D. structural protein attachment NC: 2.03 Section 2 Check

The answer is B. Selective permeability is the process in which the membrane allows some molecules to pass through, while keeping others out. NC: 2.03 Section 2 Check

Question 2 Describe the structure of the plasma membrane. NC: 2.03 Section 2 Check

The plasma membrane is composed of a phospholipid bilayer, which has two layers of phospholipids back-to-back. The polar heads of phospholipid molecules contain phosphate groups and face outward. NC: 2.03 Section 2 Check

Question 3 Phospholipid molecule Why is the phosphate group of a phospholipid important to the plasma membrane? Polar head (includes phosphate group) Nonpolar tails (fatty acids) NC: 2.03 Section 2 Check

When phospholipid molecules form a bilayer, the phosphate groups lie to the outside. Because phosphate groups are polar, they allow the cell membrane to interact with its watery (polar) environments inside and outside the cell. Phospholipid molecule Polar head (includes phosphate group) Nonpolar tails (fatty acids) NC: 2.03 Section 2 Check

Question 4 Explain why the model of the plasma membrane is called the fluid mosaic model. NC: 2.03 Section 2 Check

It is fluid because the phospholipid molecules move within the membrane. Proteins in the membrane that move among the phospholipids create the mosaic pattern. NC: 2.03 Section 2 Check

Section 3 Objectives page 179 Understand the structure and function of the parts of a typical eukaryotic cell. Explain the advantages of highly folded membranes. Compare and contrast the structures of plant and animal cells. Section 3 Objectives page 179

Section 3 Summary – page 179-187 Cellular Boundaries The plasma membrane acts as a selectively permeable membrane. Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 The cell wall The cell wall is a fairly rigid structure located outside the plasma membrane that provides additional support and protection. Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Nucleus and cell control Nucleolus Chromatin Nuclear Envelope Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Assembly, Transport, and Storage The endoplasmic reticulum (ER) is an organelle that is suspended in the cytoplasm and is the site of cellular chemical reactions. Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Assembly, Transport, and Storage Endoplasmic Reticulum (ER) Ribosomes Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Assembly, Transport, and Storage Golgi Apparatus Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Vacuoles and storage Vacuoles are membrane-bound spaces used for temporary storage of materials. Notice the difference between vacuoles in plant and animal cells. Plant Cell Vacuole Animal Cell Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Lysosomes and recycling Lysosomes are organelles that contain digestive enzymes. They digest excess or worn out organelles, food particles, and engulfed viruses or bacteria. Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Energy Transformers: Chloroplasts and energy Chloroplasts are cell organelles that capture light energy and produce food to store for a later time. Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Chloroplasts and energy The chloroplasts belongs to a group of plant organelles called plastids, which are used for storage. Chloroplasts contain green pigment called chlorophyll. Chlorophyll traps light energy and gives leaves and stems their green color. Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Mitochondria and energy Mitochondria are membrane-bound organelles in plant and animal cells that transform energy for the cell. Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Mitochondria and energy A mitochondria, like the endoplasmic reticulum, has a highly folded inner membrane. Energy storing molecules are produced on inner folds. Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Structures for Support and Locomotion Cells have a support structure called the cytoskeleton within the cytoplasm. The cytoskeleton is composed of microtubules and microfilaments. Microtubules are thin, hollow cylinders made of protein and microfilaments are thin solid protein fibers. Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Cilia and flagella Some cell surfaces have cilia and flagella, which are structures that aid in locomotion or feeding. Cilia and flagella can be distinguished by their structure and by the nature of their action. Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Cilia and flagella Cilia Cilia are short, numerous, hair-like projections that move in a wavelike motion. Section 3 Summary – page 179-187

Section 3 Summary – page 179-187 Cilia and flagella Flagella are long projections that move in a whip-like motion. Flagella and cilia are the major means of locomotion in unicellular organisms. Flagella Section 3 Summary – page 179-187

Question 1 What is the primary function of the cell wall? A. act as selectively permeable membrane B. provide support C. control activity of organelles D. acquire nutrients from environment NC: 2.02, 2.03 Section 3 Check

The answer is B. The cell wall is an inflexible, porous barrier that provides support but does not select which molecules can enter the cell. NC: 2.02, 2.03 Section 3 Check

Question 2 Describe the control center of a prokaryotic cell. Plasma membrane Ribosomes DNA Cell wall NC: 2.02 Section 3 Check

Prokaryotic cells do not have true nuclei; their DNA is not separated from the rest of the cell by a membrane. Plasma membrane Ribosomes DNA Cell wall NC: 2.02 Section 3 Check

Question 3 Which of the following structures is the site of protein synthesis? A. Golgi apparatus B. Ribosome C. Vacuole D. Lysosome NC: 2.02 Section 3 Check

The answer is B. Ribosomes are the sites where the cell produces proteins according to the directions of DNA. They can be attached to the surface of the endoplasmic reticulum or float freely in the cytoplasm. NC: 2.02 Section 3 Check

Question 4 What is the advantage of having numerous folds in the ER? A. It enables the ER to lie snugly against the nucleolus. B. It can create more vesicles in a smaller space. NC: 2.02 Section 3 Check

Question 4 What is the advantage of having numerous folds in the ER? C. It can capture more light energy with more folds. D. A large amount of work can be done in a small space. NC: 2.02 Section 3 Check

The answer is D. The ER is arranged in a series of folded membranes, which, if spread out, would take up tremendous space. NC: 2.02 Section 3 Check

Question 5 What could you predict about a plant cell that contains fewer chloroplasts than other plant cells? A. It contains less chlorophyll. B. It contains a greater number of plastids. C. It will have an increased rate of light energy capture. D. It will appear darker green in color. NC: 2.02 Section 3 Check

The answer is A. Chloroplasts are among the plant organelles known as plastids and contain the green pigment chlorophyll. Chlorophyll traps light energy from the Sun and gives leaves and stems their green color. NC: 2.02 Section 3 Check

Question 6 A mutation results in the inner membranes of a liver cell's mitochondria being smooth, rather than folded. Which of the following would you expect? A. more efficient storage of cellular energy B. It can create more vesicles in a smaller space NC: 2.02 Section 3 Check

Question 6 A mutation results in the inner membranes of a liver cell's mitochondria being smooth, rather than folded. Which of the following would you expect? C. decreased energy available to the cell D. fewer ribosomes available for protein synthesis NC: 2.02 Section 3 Check

The answer is C. Mitochondria transform energy for the cell The answer is C. Mitochondria transform energy for the cell. A highly folded inner membrane provides a greater surface area for producing energy-storing molecules. NC: 2.02 Section 3 Check

Chapter Summary – Section 1 Main Ideas Microscopes enabled biologists to see cells and develop the cell theory. The cell theory states that the cell is the basic unit of organization, all organisms are made up of one or more cells, and all cells come from preexisting cells. Chapter Summary – Section 1

Chapter Summary – Section 1 Main Ideas Continued Using electron microscopes, scientists can study cell structure in detail. Cells are classified as prokaryotic and eukaryotic based on whether or not they have membrane-bound organelles. Chapter Summary – Section 1

Chapter Summary – Section 2 Main Ideas Through selective permeability, the plasma membrane controls what enters and leaves a cell. The fluid mosaic model describes the plasma membrane as a phospholipid bilayer with embedded proteins. Chapter Summary – Section 2

Chapter Summary – Section 2 Main Ideas Eukaryotic cells have a nucleus and organelles, are enclosed by a plasma membrane, and some have a cell wall that provides support and protection. Cells make proteins on ribosomes that are often attached to the highly folded endoplasmic reticulum. Cells store materials in the Golgi apparatus and vacuoles. Chapter Summary – Section 2

Chapter Summary – Section 3 Main Ideas Continued Mitochondria break down food molecules to release energy. Chloroplasts convert light energy into chemical energy. The cytoskeleton helps maintain cell shape, is involved in the movement of organelles and cells, and resists stress placed on cells. Chapter Summary – Section 3

Question 1 Which of the following is a main idea of the cell theory? A. All organisms are composed of one cell. B. The organelle is the basic unit structure and organization of organisms. C. All cells come from two parent cells. D. All cells come from preexisting cells. NC: 2.02 Chapter Assessment

The answer is D. The cell theory states that a cell divides to form two identical cells. NC: 2.02 Chapter Assessment

Question 2 In what type of cell would you find chlorophyll? A. prokaryote B. animal C. plant D. fungus NC: 2.02 Chapter Assessment

The answer is C. Chlorophyll is the green pigment found in the chloroplasts of plant cells. NC: 2.02 Chapter Assessment

Question 3 Which of these structures packs proteins into membrane-bound structures? A. B. C. D. NC: 2.02 Chapter Assessment

Answer C depicts the Golgi apparatus, which sorts proteins and packs them into vesicles. NC: 2.02 Chapter Assessment

Question 4 Cell wall What is the difference between the cell wall and the plasma membrane? Inside cell Outside cell Plasma membrane NC: 2.02, 2.03 Chapter Assessment

The plasma membrane is a flexible boundary between the cell and its environment that controls the supply of nutrients, waste, and other products entering and leaving the cell. The cell wall is a rigid structure found in plant cells, fungi, bacteria and some protists that provides support and protection but does not select which molecules can enter or leave the cell. Cell wall Inside cell Outside cell Plasma membrane NC: 2.02, 2.03 Chapter Assessment

Question 5 Which of the following organelles is not bound by a membrane? A. ribosome B. Golgi apparatus C. vacuole D. lysosome NC: 2.02 Chapter Assessment

The answer is A. Ribosomes are simple structures made of RNA and protein and are not bound by membranes. Ribosomes NC: 2.02 Chapter Assessment

Question 6 Cholesterol molecule Explain the importance of cholesterol to the plasma membrane. Phospholipid molecules NC: 2.03 Chapter Assessment

Cholesterol helps to stabilize the phospholipids in the plasma membrane by preventing their fatty acid tails from sticking together. Phospholipid molecules Cholesterol molecule NC: 2.03 Chapter Assessment

Question 7 In which of the following pairs are the terms related? A. cell wall – selective permeability B. prokaryote – mitochondria C. microfilaments – locomotion D. plastid – storage NC: 2.02 Chapter Assessment

The answer is D. Plastids are plant organelles that are used for storage. NC: 2.02 Chapter Assessment

Question 8 Which of the following structures is found in both plant and animal cells? A. chloroplast B. cell wall C. mitochondrion D. thylakoid membrane NC: 2.02 Chapter Assessment

The answer is C. Mitochondria are the organelles in both plant and animal cells that transform energy for the cell. NC: 2.02 Chapter Assessment

Question 9 __________ span the entire plasma membrane and regulate which molecules enter and leave the cell. A. Transport proteins B. Cholesterol molecules C. Ribosomes D. Microtubules NC: 2.03 Chapter Assessment

The answer is A. Transport proteins form the selectively permeable membrane and move needed substances or waste materials through the plasma membrane. NC: 2.03 Chapter Assessment

Question 10 Compare the cytoskeleton of a cell to the skeleton of the human body. NC: 2.02, 2.03 Chapter Assessment

The cytoskeleton and skeleton are similar in that both form a framework. However, the cytoskeleton is a constantly changing structure with the ability to be disassembled in one place and reassembled in another. NC: 2.02, 2.03 Chapter Assessment

2. DNA 3. Plasma membrane 1. Ribosomes 4. Cell wall A prokaryotic cell does not have internal organelles surrounded by a membrane. Most of a prokaryote’s metabolism takes place in the cytoplasm. 2. DNA 3. Plasma membrane 1. Ribosomes 4. Cell wall Click here to return to chapter summary NC: 2.02, 2.03 Chapter Assessment

1. Nucleus 2. Nucleolus 3. Chromosomes 4. Plasma membrane This eukaryotic cell from an animal has distinct membrane-bound organelles that allow different parts of the cell to perform different functions. 1. Nucleus 2. Nucleolus 3. Chromosomes 4. Plasma membrane Click here to return to chapter summary 5. Organelles NC: 2.02, 2.03 Chapter Assessment

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