Chapter 1: The Study of Life (PDF)

# Chapter 1: The Study of Life ## 1.1 The Science of Biology - Identify the shared characteristics of the natural sciences - Summarize the steps of the scientific method - Compare inductive reasoning with deductive reasoning - Describe the goals of basic science and applied science ### What is bi...

# Chapter 1: The Study of Life ## 1.1 The Science of Biology - Identify the shared characteristics of the natural sciences - Summarize the steps of the scientific method - Compare inductive reasoning with deductive reasoning - Describe the goals of basic science and applied science ### What is biology? Biology is the study of life. It encompasses everything from the microscopic view of a cell to ecosystems and the whole living planet. It covers recent news topics such as Escherichia coli outbreaks in spinach and Salmonella contamination in peanut butter. It includes efforts toward finding a cure for AIDS, Alzheimer's disease, and cancer. On a global scale, many researchers are committed to finding ways to protect the planet, solve environmental issues, and reduce the effects of climate change. ### The Process of Science Science is knowledge that covers general truths or the operation of general laws, especially when acquired and tested by the scientific method. The scientific method plays a major role in science. It is a method of research with defined steps that include experiments and careful observation. One of the most important aspects of the scientific method is the testing of hypotheses by means of repeatable experiments. A hypothesis is a suggested explanation for an event which one can test. - **repeatable experiments** - the scientific method is less applicable in disciplines like archaeology, psychology, and geology because repeating experiments becomes more difficult. - **verified theory** - A theory is a tested and confirmed explanation for observations or phenomena. - **natural sciences** - those fields of science related to the physical world and its phenomena and processes. ### Natural Sciences Natural sciences include: - Astronomy - Biology - Computer sciences - Geology - Logic - Physics - Chemistry - Mathematics ### Scientific Reasoning Scientists use two methods of logical thinking: - **Inductive Reasoning** - uses related observations to arrive at a general conclusion. It is common in descriptive science and involves formulating generalizations inferred from careful observation and analyzing a large amount of data. - **Deductive Reasoning** - uses a general principle or law to forecast specific results. It is a form of logical thinking that uses a general principle or law to forecast specific results. ### The Scientific Method The scientific method is an approach common to other sciences as well. The steps that the scientific method uses can be applied to solving problems that aren't necessarily scientific in nature. - **Observation** - often a problem to solve that leads to a question. - **Proposing a Hypothesis** - a suggested explanation for an event, which one can test. - **Making a Prediction** - a hypothesis but it typically has the format "If... then...." - **Testing a Hypothesis** - conduct one or more experiments designed to eliminate one or more of the hypotheses. The control group contains every feature of the experimental group except it is not given the manipulation that the researcher hypothesizes. Therefore, if the experimental group's results differ from the control group, the difference must be due to the hypothesized manipulation, rather than some outside factor. - **Analyze the results** - one can propose a new hypothesis. - **Report results** ### Two Types of Science - **Basic Science** or "pure" science seeks to expand knowledge regardless of the short-term application of that knowledge. It is not focused on developing a product or a service of immediate public or commercial value. - **Applied Science** or "technology," aims to use science to solve real-world problems, making it possible, for example, to improve a crop yield, find a cure for a particular disease, or save animals threatened by a natural disaster. ### Reporting Scientific Work - **Peer Review:** scientists share results by presenting them at a scientific meeting or conference, but this approach can reach only the select few who are present. Instead, most scientists present their results in peer-reviewed manuscripts that are published in scientific journals. - **Scientific Paper:** A scientific paper consists of several specific sections: - Introduction - Materials and Methods - Results - Discussion - Acknowledgments - References - Abstract ## 1.2 Themes and Concepts of Biology - Identify and describe the properties of life - Describe the levels of organization among living things - Recognize and interpret a phylogenetic tree - List examples of different subdisciplines in biology ### Properties of Life - **Order** - **Sensitivity or Response to Stimuli** - **Reproduction** - **Adaptation** - **Growth and Development** - **Regulation/Homeostasis** - **Energy Processing** - **Evolution** ### Levels of Organization of Living Things - **Atom:** the smallest and most fundamental unit of matter. - **Molecule:** a chemical structure consisting of at least two atoms held together by one or more chemical bonds. - **Macromolecule:** large molecules that are typically formed by polymerization. - **Organelles:** small structures that exist within cells. - **Cells:** the smallest fundamental unit of structure and function in living organisms. - **Tissues:** groups of similar cells carrying out similar or related functions. - **Organs:** collections of tissues grouped together performing a common function. - **Organ System** : functionally related organs. - **Organisms:** individual living entities. - **Populations:** all the individuals of a species living within a specific area. - **Communities:** the sum of populations inhabiting a particular area. - **Ecosystems:** all the living things in a particular area together with the abiotic, nonliving parts of that environment. - **Biosphere:** the collection of all ecosystems and represents the zones of life on Earth. ### The Diversity of Life The source of diversity is **evolution**; the process of gradual change in a population or species over time. Evolutionary biologists study the evolution of living things in everything from the microscopic world to ecosystems. - **Phylogenetic tree**: a diagram showing the evolutionary relationships among biological species based on similarities and differences in genetic or physical traits or both. ### Branches of Biological Study - **Molecular Biology and Biochemistry** - **Microbiology** - **Neurobiology** - **Paleontology** - **Zoology** - **Botany** - **Biotechnology** - **Ecology** - **Physiology**