The Science of BiologyChapter 1 Mrs. Norris Spring 2013
Vocabulary: Write This Downon Chapter 1 Glossary Page! • Science- an organized way of using evidence to learn about the world • Inference- a logical interpretation based on prior knowledge or experience • Hypothesis – a scientific explanation for a set of observations • Theory- a well-supported, well-tested hypothesis that unifies a broad range of observations. Not absolute.
What is 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.
What is Science? • SCIENCE is an organized way of using evidence to learn about the natural world. • The word SCIENCE also refers to the body of knowledge that scientists have built up after years of using this process • Science is a way of knowing – an ongoing process that questions the world around us.
Observation • The work of scientists begins with making careful observations– the process of gathering info about events or processes in a careful and orderly way. • Generally uses the senses.
Data- information gathered from observations. There are 2 types of data: 1. Quantitative- expressed as numbers found by counting or measuring. 2. Qualitative- descriptive and involve characteristics that can’t be counted.
Scientists use data to make inferences – a logical interpretation of data or evidence collected. Example: if you see wet pavement, it may have rained
Explaining and Interpreting Data • After making observations, researchers will propose one or more hypotheses. • A hypothesis is a proposed scientific explanation (or an educated guess) for a set of observations • Scientists generate hypotheses using prior knowledge, or what they already know; logical inference; and informed, creative imagination.
Explaining and Interpreting Data • In science, a hypothesis is useful only if it can be tested! • Research! The ability to reproduce results is an important part of any experiment! • Hypotheses can then be either ruled out or confirmed and supported. • Collaboration is key!
Analyzing data: • Study the graph on page 27 of the textbook and answer questions 1-5 (you do NOT have to write the Question). • TURN IT IN!
Scientific Theories When enough experimental data support a hypothesis, the hypothesis becomes a theory. A theory attempts to explain everything about a phenomenon including it’s cause. A theory is a well-tested explanation that unifies a broad range of observations
Scientific Law A statement that describes some aspect of a phenomenon that is TRUE Does not explain how or why Example: The law of gravity
Check Point 1.1: Write Questions and Answers!! • How does an observation about an object differ from an inference about that object? • An observation uses senses to gather information; an inference is a logical interpretation based on what you already know and have experienced. • What is Biology the study of? • The living world
Vocabulary: Write This Downon Chapter 1 Glossary Page! • Controlled experiment: testing a hypothesis by changing only one variable at a time while all other variables are unchanged, or controlled • Variables: Factors that can be changed in an experiment • Controlled variables: unchanged, remains the same • Independent (manipulated variable): Variable that is changed • Dependent (responding variable): the response to the independent variable
Scientific Method Foldable Ask a question/State the Problem Form a hypothesis Must be testable. If…..then format Test the hypothesis with a controlled experiments Analyze data Draw conclusions and Record results MAKE FOLDBALE! Simpsons! Running in the Rain!
Vocabulary: Write This Downon Chapter 1 Glossary Page! • Metric System – a decimal system of measurements based on multiples of 10 • Meter- basic unit of length • Liter- basic unit of volume • Gram – basic unit of mass • Kelvin or Celsius- basic units of temperature • Climbing the Stairs Graphic
Tools and Procedures:Measurements Scientists use a universal system of measurement called Systeme International (SI) or the Metric System Importance of a common system – allows scientists all over the world to communicate with each other and share data.
Sample Problems: Work these! 25.8 g = __________ kg 1000 g = _________ kg 45.9 cm = ________ m 100 m = __________ mm 75.2 mL = ________ L 10 dm = __________ m 27 L = ____________ kL
Sample Problems 25.8 g = .0258 kg 1000 g = 1 kg 45.9 cm = .459 m 100 m = 100 000 mm 75.2 mL = .0752 L 10 dm = 1.0 m 27 L = .027 kL Length Lab, Practice Problems
Line graphs When graphing the data from an experiment-- • The graph should have a title • The graph should be drawn to scale • Independent variable (manipulated variable)- goes on the X axis • Dependent variable (resulting variable) –goes on the Y axis
Tools of the Trade:The Microscope Allows scientists to see objects that would never be seen with the unaided eye
Three Types of Microscopes Simple Microscope – Consists of only a single lens Light Microscope – consists of two lens. One lens magnifies the object and the other magnifies image. (Good for observing small, living organisms) Electron Microscope – electron beams are passed through the specimen and the image is projected onto a monitor. Better resolution and magnification. Two types – TEM and SEM
Lab Techniques • Cell cultures- single cell in a nutrient solution– then that cell produces many cells • Cell fractionation- cell is separated into different cell parts • Common Lab Equipment Worksheet • Starting with Safety Video
Studying Life- Branches of BiologyADD TO CH. 1 Glossary!!! Botany – study of plants Zoology – study of animals Ecology – study of interactions between living things and their environment Genetics – study of heredity Microbiology – study of microorganisms Evolution – study of living things changing over time Biochemistry – study of organic molecules
8 levels of organization in biology. You must know these! (Write it Down!) 1. Molecules- groups of atoms 2. Cells- smallest functional unit of a living organism 3. Groups of cells- tissues, organs 4. Organism- tree, dog, you 5. Population- Groups of organisms of one type in a defined area 6. Community- Different populations that live together in a defined area 7. Ecosystem- Community and its nonliving surroundings in a defined area 8. Biosphere- part of the Earth that contains all ecosystems, or all life
8 Characteristics of Living Things. You must know! Write it down! • Made up of cells • Can reproduce • Have a genetic code • Grow and develop • Obtain and use materials and energy • Respond to the environment:Homeostasis • Maintain a stable internal environment • Changes over time
I. Living things are made up of cells • Cells – smallest unit of life • Unicellular organisms- consist of only a single cell • Multicellular organisms- contain more than one cell • The human body has over 85 different types of cells.
II. All living things reproduce 2 types of reproduction: • Sexual Reproduction- cells from two different parents unite to form the first cell of a new organism • Asexual Reproduction- new organism has a single parent (ex.- hydra)
III. Genetic Code • Directions for inheritance come from DNA IV. Grow and Develop • Life cycles involve growth and development
V. Living Things Obtain and Use Materials and Energy • Metabolism: chemical reactions through which organisms break down materials • Photosynthesis: the way plants, most algae, and some bacteria obtain their energy- process of converting light energy into stored energy. • Decomposers: obtain materials from remains of dead organisms
VI. Respond to the environment • Organisms respond to stimuli from the environment – (ex: light, temperature, food) VII. Maintain internal balance • Homeostasis-process by which organisms maintain a stable internal balance– to stay the same. • Ex. – body temperature
VIII. Change over time • Taken as a group, all living things change over time: Evolution