Biology Exploring Life CHAPTER 1 Power Point Lectures

Biology: Exploring Life CHAPTER 1 Power. Point Lectures for Campbell Biology: Concepts & Connections, Seventh Edition Reece, Taylor, Simon, and Dickey © 2012 Pearson Education, Inc. Lecture by Edward J. Zalisko

FIGURE 1. 0_1 Chapter 1: Big Ideas Themes in the Study of Biology The Process of Science Evolution, the Core Theme of Biology and Everyday Life

� Biology is the scientific study of life. � Properties of life include Order—the highly ordered structure that typifies life, 2. Reproduction—the ability of organisms to reproduce their own kind, 3. Growth and development—consistent growth and development controlled by inherited DNA, 4. Energy processing—the use of chemical energy to power an organism’s activities and chemical reactions, 1. © 2012 Pearson Education, Inc.

Response to the environment—an ability to respond to environmental stimuli, 6. Regulation—an ability to control an organism’s internal environment within limits that sustain life, and 7. Evolutionary adaptation—adaptations evolve over many generations as individuals with traits best suited to their environments have greater reproductive success and pass their traits to offspring. 5. © 2012 Pearson Education, Inc.

Ecosystem: Forest in Madagascar Biosphere Community: All organisms in the forest Population: Group of ring-tailed lemurs Organism: Ring-tailed lemur

FIGURE 1. 2_2 Organism: Ring-tailed lemur Spinal cord Organ system: Brain Nervous system Organ: Brain Nerve Tissue: Nervous tissue Atom Cell: Nerve cell Nucleus Organelle: Nucleus Molecule: DNA

� Cells are the level at which the properties of life emerge. � A cell can � � � regulate its internal environment, take in and use energy, respond to its environment, develop and maintain its complex organization, and give rise to new cells. © 2012 Pearson Education, Inc.

� All cells are enclosed by a membrane that regulates the passage of materials between the cell and its surroundings and � use DNA as their genetic information. � © 2012 Pearson Education, Inc.

� There 1. 2. are two basic types of cells. Prokaryotic cells were the first to evolve, are simpler, and are usually smaller than eukaryotic cells. bacteria Eukaryotic cells contain membrane-enclosed organelles, including a nucleus containing DNA, and are found in plants, animals, and fungi. © 2012 Pearson Education, Inc.

FIGURE 1. 3 Eukaryotic cell DNA (no nucleus) Prokaryotic cell Membrane Organelles Nucleus (membraneenclosed) DNA (throughout nucleus)

� Cells illustrate another theme in biology: the correlation of structure and function. � Structure is related to function at all levels of biological organization. © 2012 Pearson Education, Inc.

� Living organisms interact with their environments, which include other organisms and physical (nonliving) factors. � In most ecosystems plants are the producers that provide the food, � consumers eat plants and other animals, and � decomposers act as recyclers, changing complex matter into simpler mineral nutrients. � © 2012 Pearson Education, Inc.

Figure 1. 4 Ecosystem O 2 Sunlight Heat Producers (such as plants) Consumers (such as animals) Chemical energy (food) CO 2 Water and minerals taken up by tree roots CO 2 Cycling of chemical nutrients Decomposers (in soil)

� All cells have DNA, the chemical substance of genes. � Genes are the unit of inheritance that transmits information from parents to offspring, � are grouped into very long DNA molecules called chromosomes, and � control the activities of a cell. � © 2012 Pearson Education, Inc.

�A species’ genes are coded in the sequences of the four building blocks making up DNA’s double helix. All forms of life use essentially the same code to translate the information stored in DNA into proteins. � The diversity of life arises from differences in DNA sequences. � © 2012 Pearson Education, Inc.

� Diversity is the hallmark of life. Biologists have identified about 1. 8 million species. � Estimates of the actual number of species ranges from 10 to 100 million. � � Taxonomy names species and classifies them into a system of broader groups. © 2012 Pearson Education, Inc.

� The diversity of life can be arranged into three domains. Bacteria are the most diverse and widespread prokaryotes. 2. Archaea are prokaryotes that often live in Earth’s extreme environments. 3. Eukarya have eukaryotic cells and include single-celled protists and multicellular fungi, animals, and plants. 1. © 2012 Pearson Education, Inc.

FIGURE 1. 6 Domain Bacteria Domain Eukarya Bacteria Domain Archaea Protists (multiple kingdoms) Kingdom Plantae Kingdom Fungi Kingdom Animalia Archaea

� The history of life, as documented by fossils, is a saga of a changing Earth billions of years old and � inhabited by an evolving cast of life forms. � © 2012 Pearson Education, Inc.

� In 1859, Charles Darwin published the book On the Origin of Species by Means of Natural Selection, which articulated two main points. 1. A large amount of evidence supports the idea of evolution, that species living today are descendants of ancestral species in what Darwin called “descent with modification. ” 2. Natural selection is a mechanism for evolution. © 2012 Pearson Education, Inc.

� Evolution is a core theme of biology. � Evolutionary theory is useful in medicine � agriculture � forensics � Conservation � � Human-caused environmental changes are powerful selective forces that affect the evolution of many species, including antibiotic-resistant bacteria, � pesticide-resistant pests, � endangered species, and � increasing rates of extinction. � © 2012 Pearson Education, Inc.

�The word science is derived from a Latin verb meaning “to know. ” Science is a way of knowing. �Science © 2012 Pearson Education, Inc. is a process not a thing.

� How is a theory different from a hypothesis? A scientific theory is � much broader in scope than a hypothesis, � usually general enough to generate many new, specific hypotheses, which can then be tested, and � supported by a large and usually growing body of evidence. © 2012 Pearson Education, Inc.

General Stages of Scientific Investigation • 1. 2. 3. 4. 5. 6. Asking a Question Collecting Information/Making observations Inferring and forming a hypothesis Designing a controlled experiment to test the hypothesis Collecting/Analyzing Data (qualitative vs. quantitative) Drawing Conclusions

� Inference and imagination can lead to a hypothesis. � If. . then format Example: � § If artificial king snakes are placed in an environment without coral snakes, then they will be attacked more frequently than the artificial brown snakes.

Variables – factors that change Independent – you manipulate (what you deliberately change) Dependent – change in response to the independent variable (variable that is measured) Control Group – used for comparison Nothing is changed

Case Study � Scientists began with a set of observations and generalizations poisonous animals are brightly colored and � imposters resemble poisonous species but are actually harmless. � � They then tested the hypothesis that mimics benefit because predators confuse them with the harmful species. © 2012 Pearson Education, Inc.

� The scientists conducted a controlled experiment, comparing an experimental group consisting of artificial king snakes � a control group consisting of artificial brown snakes. � The groups differed only by one factor, the coloration of the artificial snakes. � The data fit the key prediction of the mimicry hypothesis. � © 2012 Pearson Education, Inc.

Figure 1. 9 E Percent of total attacks on artificial snakes 100 84% 83% Artificial king snakes 80 Artificial brown snakes 60 40 20 0 17% Coral snakes absent 16% Coral snakes present

� Science is a social activity with most scientists working in teams. � Scientists share information in many ways. � Science seeks natural causes for natural phenomena. � The scope of science is limited to the study of structures and processes that we can directly observe and measure. © 2012 Pearson Education, Inc.

� The graph below shows the results of an experiment in which mice learned to run through a maze. 1. 2. 3. 4. State the hypothesis that you think this experiment tested. Identify the variables and control group. What variables that must have been kept constant so as not to affect the results (validity). Looking at the data collected, does it support the hypothesis? Explain.

� Many issues facing society are related to biology. Most involve our expanding technology. � The basic goals of science and technology differ. � The goal of science is to understand natural phenomena. � The goal of technology is to apply scientific knowledge for some specific purpose. © 2012 Pearson Education, Inc.

� Although their goals differ, science and technology are interdependent. Technological advances stem from scientific research. � Research benefits from new technologies. � © 2012 Pearson Education, Inc.

1. 2. 3. 4. Describe seven properties common to all life. Describe the levels of biological organization from molecules to the biosphere, noting the interrelationships between levels. Define the concept of emergent properties and describe an example of it. Explain why cells are a special level in biological organization. Compare prokaryotic and eukaryotic cells. © 2012 Pearson Education, Inc.

5. 6. 7. 8. 9. 10. Compare three domains of life. Describe the process and products of natural selection. Distinguish between quantitative and qualitative data. Distinguish between the scientific definition and common use of the word theory. Describe the structure of a controlled experiment and give an example. Compare the goals of science and technology. Explain why an understanding of science is essential to our lives. © 2012 Pearson Education, Inc.