Biology and You Section 1: Themes of Biology Chapter 1 Biology and You Section 1: Themes of Biology Section 2: Biology in Your World Section 3: Scientific Processes 1

Themes of Biology Objectives: Section 1 Themes of Biology Objectives: Relate the seven properties of life to a living organism. Describe seven themes that can help you organize what you learn about biology. Identify the tiny structures that make up all living organisms. Differentiate between reproduction and heredity and between metabolism and homeostasis. 2

Themes of Biology Characteristics of Living Organisms Section 1 Themes of Biology Characteristics of Living Organisms Organisms Living organisms are diverse but share certain characteristics. Properties of Life Seven themes unify the science of biology: cellular structure and function, reproduction, metabolism, homeostasis, heredity, evolution, and interdependence. 3

Themes of Biology Unifying Themes of Biology Section 1 Themes of Biology Unifying Themes of Biology Cellular Structure and Function All living organisms are composed of cells. Reproduction Living organisms reproduce, producing offspring similar to themselves. Metabolism Living organisms obtain and use energy to stay alive, grow, and develop. Homeostasis All living organisms respond to their environment and are able to maintain homeostasis. 4

Themes of Biology Unifying Themes of Biology continued Section 1 Themes of Biology Unifying Themes of Biology continued Heredity All living things are able to pass on traits to their offspring through genes that are passed from parent to offspring each generation. Evolution Evolution has shaped all of life’s diversity. Interdependence All living organisms depend on one another and their environment. 5

Biology in Your World Objectives: Section 2 Biology in Your World Objectives: Evaluate the impact of scientific research on the environment. Evaluate the impact of scientific research on society with respect to increasing food supplies. Explain the primary task of the Human Genome Project. Describe the contributions of scientists in fighting AIDS and cancer. Define the term gene therapy. 6

Biology in Your World Solving Real-World Problems Section 2 Biology in Your World Solving Real-World Problems Preserving Our Environment Pollution of the atmosphere, extinction of plants and animals, and a growing demand for food are current environmental problems caused by the growing human population. Improving the Food Supply Genetic engineering is used to develop crops that require fewer fertilizers and pesticides and to develop new crops. Understanding the Human Genome Scientists are sequencing every human gene, which will be an invaluable tool in medical research. 7

Biology in Your World Fighting Disease Section 2 Biology in Your World Fighting Disease AIDS and Cancer Biological research and new technologies will help scientists battle diseases such as AIDS and cancer. Emerging Diseases The past few years have seen the emergence of new diseases from other parts of the world such as West Nile virus. Gene Therapy Gene therapy will help scientists fight genetic disorders such as cystic fibrosis, muscular dystrophy, and hemophilia. 8

Scientific Processes Objectives: Section 3 Scientific Processes Objectives: Describe the stages common to scientific investigations. Distinguish between forming a hypothesis and making a prediction. Differentiate a control group from an experimental group and an independent variable from a dependent variable. Define the word theory as used by a scientist. 9

Scientific Processes Observation: The Basis of Scientific Research Section 3 Scientific Processes Observation: The Basis of Scientific Research Solving Scientific Puzzles All scientists have a certain way of investigating the world. Observation Observation is the act of noting or perceiving objects or events using the senses. 10

Scientific Processes Stages of Scientific Investigations Section 3 Scientific Processes Stages of Scientific Investigations Collecting Observations and Asking Questions Scientists add to scientific knowledge by sharing observations and posing questions about observations. Forming Hypotheses and Making Predictions Forming and testing hypotheses, as well as making predictions, are important in scientific investigations. Confirming Predictions In a controlled experiment, the independent variable is varied between the experimental and control groups. The measured variable is the dependent variable. 11

Scientific Processes Stages of Scientific Investigations continued Section 3 Scientific Processes Stages of Scientific Investigations continued Drawing Conclusions Hypotheses can be supported or rejected, but never proven. Viewing Conclusions in Context Many important scientific questions have more than one answer, such as in determining the causes of the global decline in amphibians. 12

Scientific Processes Scientific Explanations Section 3 Scientific Processes Scientific Explanations Constructing a Theory A collection of hypotheses that have been repeatedly tested and are supported by a great deal of evidence forms a theory. 13