The Science of Biology

Transcription

1 Chapter 1 The Science of Biology Section 1 1 What Is Science? (pages 3 7) This section explains what the goal of science is and describes a scientific view of the world. What Science Is and Is Not (page 3) 1. What is the goal of science? The goal of science is to investigate and understand nature, to explain events in nature, and to use those explanations to make useful predictions. 2. What is science? Science is an organized way of using evidence to learn about the natural world. Evidence Based on Observation (page 4) 3. What does observation involve? Observation involves using one or more of the senses sight, hearing, touch, smell, and sometimes taste to gather information. 4. The information gathered from observation is called evidence, or data. 5. Complete the table about types of observations. TYPES OF OBSERVATIONS Type of Observations Observations Involve Example Quantitative Numbers There are seven birds at the feeder. Qualitative Characteristics that cannot be One of the birds has a red head. easily measured or counted Interpreting the Evidence (page 4) 6. What is an inference? An inference is a logical interpretation based on prior knowledge and experience. Explaining the Evidence (page 5) 7. What is a hypothesis? A hypothesis is a possible explanation for a set of observations or an answer to a scientific question. 8. In science, a hypothesis is useful only if it can be tested. 9. Is the following sentence true or false? A hypothesis should be stated in such a way that it can never be proved wrong. false Guided Reading and Study Workbook/Chapter 1 5

2 Chapter 1, The Science of Biology (continued) 10. What are three ways from which hypotheses may arise? a. From prior knowledge b. From logical inferences c. From imaginative guesses 11. Circle the letter of each of the following that may be an outcome of testing a hypothesis. a. The hypothesis is partly true but needs to be revised. b. The hypothesis is wrong. c. The hypothesis is supported. d. The hypothesis is of no value. A Scientific View of the World (page 6) 12. What do scientists assume can be discovered through scientific inquiry? discovered. They assume that the basic rules that apply to all events in the universe can be 13. What are some qualities that are desirable in a scientist? Qualities include curiosity, honesty, openness, skepticism, and a recognition that science has limits. Science and Human Values (page 7) 14. Is the following sentence true or false? A community must use its shared values to make decisions about scientific issues. true Section 1 2 How Scientists Work (pages 8 15) This section explains how scientists test hypotheses. It also describes how a scientific theory develops. Designing an Experiment (pages 8 10) 1. The idea that life can arise from nonliving matter is called spontaneous generation. 2. What was Francesco Redi s hypothesis about the appearance of maggots? Flies produce maggots. 3. What are variables in an experiment? They are factors that can change. 4. Ideally, how many variables should an experiment test? It should test only one variable at a time. 5. When a variable is kept unchanged in an experiment, it is said to be controlled. 6. What is a controlled experiment? A controlled experiment is an experiment in which one variable is changed while the other variables are controlled. 6 Guided Reading and Study Workbook/Chapter 1

3 7. Complete the table about variables. VARIABLES Type of Variable Manipulated variable Responding variable Definition The variable that is deliberately changed in an experiment The variable that is observed and changes in response to the manipulated variable 8. In Redi s experiment, what were the manipulated variable and the responding variable? The manipulated variable was the presence or absence of the gauze covering, and the responding variable was whether maggots appear. 9. The illustration below shows the beginning of Redi s experiment. Complete the illustration by showing the outcome. Redi s Experiment on Spontaneous Generation Uncovered jars Covered jars Several days pass. Maggots appear No maggots appear 10. For what do scientists use the data from a controlled experiment? They use it to evaluate the hypothesis and draw a conclusion. 11. When scientists look for explanations for specific observations, what do they assume about nature? They assume that the patterns in nature are consistent. Publishing and Repeating Investigations (pages 10 13) 12. Why do scientists assume that experimental results can be reproduced? A key assumption in science is that nature behaves in a consistent manner. Guided Reading and Study Workbook/Chapter 1 7

4 Chapter 1, The Science of Biology (continued) 13. What did Anton van Leeuwenhoek discover? He discovered a world of tiny moving objects in rainwater, pond water, and dust that he called animalcules. 14. What did John Needham conclude from his test of Redi s findings? He concluded that the little animals in a bottle of gravy could only have come from the juice of the gravy. 15. What did Spallanzani do to improve upon Redi s and Needham s work? He boiled two containers of gravy, assuming that the boiling would kill any microorganisms that were present. 16. How did Pasteur settle the spontaneous generation argument? He designed a special flask that showed as long as broth was protected from microorganisms, it remained free of living things. When Experiments Are Not Possible (page 14) 17. In animal field studies, why do scientists usually try to work without making the animals aware that humans are present? To learn how animals in the wild interact, it is necessary to observe the animals without disturbing them. 18. When a controlled experiment is not possible, why do scientists try to identify as many relevant variables as possible? They identify as many as possible so that most variables are controlled. How a Theory Develops (pages 14 15) 19. The theory that new organisms come from existing organisms is called biogenesis. 20. In science, what is a theory? A theory is a well-tested explanation that unifies a broad range of observations. 21. Is the following sentence true or false? A theory may be revised or replaced by a more useful explanation. true Reading Skill Practice A flowchart can help you remember the order in which a set of events has occurred or should occur. On a separate sheet of paper, create a flowchart that represents the process that Redi carried out in his investigation of spontaneous generation. This process is explained under the heading Designing an Experiment on pages For more information about flowcharts, see Organizing Information in Appendix A of your textbook. Students flowcharts should begin with Redi s proposal of a hypothesis and end with his drawing a conclusion about how maggots are produced. 8 Guided Reading and Study Workbook/Chapter 1

5 Section 1 3 Studying Life (pages 16 22) This section describes some characteristics of living things. It also explains how life can be studied at different levels. Introduction (page 16) 1. What is biology? Biology is the science that seeks to understand the living world. Characteristics of Living Things (pages 16 20) 2. What is a cell? A cell is a collection of living matter enclosed by a barrier that separates the cell from its surroundings. 3. Circle the letter of each sentence that is true about cells. a. A cell is the smallest unit of an organism that can be considered alive. b. A multicellular organism may contain trillions of cells. c. A living thing that consists of a single cell is a multicellular organism. d. Organisms are made up of cells. 4. What are two types of asexual reproduction? a. A single-celled organism divides in half to form two new organisms. b. A portion of an organism splits off to form a new organism. 5. Living things are based on a universal genetic code. 6. Circle the letter of each sentence that is true about living things. a. The life cycle of many organisms involves development. b. All living things grow during at least part of their lives. c. Each type of organism has a distinctive life cycle. d. Cells may change in number but never differentiate. 7. Why does an organism need energy and a constant supply of materials? An organism uses energy and materials to grow, develop, and reproduce. 8. What is metabolism? It is the combination of reactions through which an organism builds up or breaks down materials as it carries out its life processes. 9. Is the following sentence true or false? All organisms respond to the environment in exactly the same ways. false 10. What is homeostasis? It is the process by which organisms keep their internal conditions relatively stable. Guided Reading and Study Workbook/Chapter 1 9

6 Chapter 1, The Science of Biology (continued) 11. A group of organisms that changes over time is said to evolve. Branches of Biology (pages 20 21) Match the different kinds of biologists with the focus of their study. Kinds of Biologists Focus of Study d 12. Zoologist a. Animal behavior b 13. Botanist b. Plants a 14. Ethologist c. Ancient life c 15. Paleontologist d. Animals 16. Label each of the illustrations below according to the level of study represented. Population Biosphere Cells 17. The largest level of biological study is the biosphere. Biology in Everyday Life (page 22) 18. What can the study of biology provide to the decision makers about matters affecting human society? Biology can provide them with useful information and analytical skills. It can help them envision the possible effects of their decisions. Section 1 4 Tools and Procedures (pages 24 28) This section describes the measurement system that most scientists use. It also describes light microscopes, electron microscopes, and laboratory techniques. A Common Measurement System (page 24) 1. Why do scientists need a common system of measurement? Researchers need to replicate each other s experiments, and most experiments involve measurements. 2. When collecting data and doing experiments, what system of measurement do most scientists use? Metric system 10 Guided Reading and Study Workbook/Chapter 1

7 3. What is the metric system? The metric system is a decimal system of measurement whose units are based on certain physical standards and are scaled on multiples of Complete each equation by writing the correct number or metric unit. a meters = 1 b. 1 liter = 1000 kilometer milliliters c. 1 gram = 1000 milligrams d kilograms = 1 metric ton Analyzing Biological Data (page 25) 5. When scientists collect data, what are they often trying to find out? They are trying to find out whether certain factors changed or remained the same. 6. What does a graph of data make easier to recognize and understand than a table of data? A pattern Microscopes (pages 25 26) 7. What are microscopes? Microscopes are devices that produce magnified images of structures that are too small to see with the unaided eye. 8. What are compound light microscopes? They are microscopes that allow light to pass through the specimen and use two lenses to form an image. 9. How do chemical stains make light microscopes more useful? They can show specific structures in the cell. 10. What are the two main types of electron microscopes? a. Transmission electron microscopes (TEMs) b. Scanning electron microscopes (SEMs) 11. Compare how a TEM and an SEM produce images. A TEM shines a beam of electrons through a thin specimen, while an SEM runs a beam of electrons back and forth across the surface of a specimen. 12. How must samples be prepared for observation by an electron microscope? Samples must be completely dried out. Laboratory Techniques (page 27) 13. A group of cells grown in a nutrient solution from a single original cell is called a(an) cell culture. 14. What technique do biologists use to separate one part of a cell from the rest of the cell? Cell fractionation Guided Reading and Study Workbook/Chapter 1 11

8 Chapter 1, The Science of Biology (continued) Working Safely in Biology (page 28) 15. What is the single most important rule for your safety while working in a laboratory? exactly. WordWise Always follow your teacher s instructions and the textbook directions The block of letters below contains six vocabulary terms from Chapter 1. Use the clues to identify the words you need to find. Then, find the words across, down, or on the diagonal. Circle each word in the hidden-word puzzle. Clues A device that produces magnified images of structures that are too small to see with the unaided eye A well-tested explanation that unifies a broad range of observations Change over time The process by which organisms keep their internal conditions relatively stable An organized way of using evidence to learn about the natural world Evidence gathered from observations The chemical reactions through which an organism builds up or breaks down materials A collection of living matter enclosed by a barrier that separates it from the surroundings Vocabulary Terms microscope theory evolve homeostasis science data metabolism cell h o m e o s t a s i s h n s q a a l e s n m m t c e l l s v m s s h y i d o s z o u p b t m e t a b o l i s m r w n l s t x v m s s m i c l s v a e d a h t h e o r y l m e a n m m i c r o s c o p e 12 Guided Reading and Study Workbook/Chapter 1