Biology Miller And Levine Unit 1 Test Questions And Correct Answers

Biology Miller And Levine Unit 1 Test Questions And Correct Answers Radioactive Isotopes - ANSWER -Isotopes whose nuclei are unstable and break down at a constant rate over time Chemical Compound - ANSWER -A substance formed by chemical union of two or more elements or ingredients in definite proportion by weight Chemical Formula - ANSWER -Shows the composition of compounds Ions - ANSWER -Electrically charged atoms that have gained or lost electrons. Ionic Bond - ANSWER -A chemical bond in which one atom loses an electron to form a positive ion and the other atom gains to electron to form a negative ion Covalent Bonds - ANSWER -Formed when electrons are shared between atoms Single covalent bond - ANSWER -When atoms share two electrons Double covalent bond - ANSWER -When atoms share four electrons Triple covalent bond - ANSWER -When atoms share six electrons Molecule - ANSWER -*Two or more atoms held together by covalent bonds* The smallest unit of most compounds *Can also be created when atoms of the same element join together* Van der Waals Forces - ANSWER -A slight attraction that develops between the oppositely charged regions of nearby molecules Hydrogen Bond - ANSWER -The attraction between a hydrogen atom with a partial positive charge and another atom with a partial negative charge Cohesion - ANSWER -An attraction between molecules of the same substance Adhesion - ANSWER -An attraction between molecules of different substances If several variables are changed in the experiment, researchers can't easily tell which variable is responsible for any results they observe - ANSWER -Why is it important to control variables? Independent Variable - ANSWER -The experimental factor that is manipulated; the variable whose effect is being studied. Dependent Variable - ANSWER -The variable that is measured in an experiment, the outcome factor; the variable that may change in response to manipulations of the independent variable The variable that is measured Control Group - ANSWER -In an experiment, the group that is not exposed to the treatment; contrasts with the experimental group and serves as a comparison for evaluating the effect of the treatment. Constant - ANSWER -Any variable that can stay the same in an experiment Data - ANSWER -Information gathered from experimental observations Quantitative Data - ANSWER -Numbers obtained by counting or measuring Qualitative Data - ANSWER -This is descriptive and involves characteristics that cannot usually be counted Research tools - ANSWER -*Used to gather data* Ex: metersticks, calculators, microscopes, micropipettes, machines, etc. Organizing data - ANSWER -What are charts and graphs used for? *Certain tools have limited accuracy* Data analyses can be misinterpreted *Sample sizes are not always chosen carefully* - ANSWER -What are sources of error that scientists may run into while testing a hypothesis? Because there is always variation among individuals in control and experimental groups. The larger the sample size, the more reliably researchers can analyze that variation and evaluate the differences between experimental and control groups. - ANSWER -Why should experimental and control groups be large? No - ANSWER -Are experiments always successful after the first try? They create a hypothesis that can be tested by observations - ANSWER -If experiments are not possible, how do scientists test their hypothesis? Law - ANSWER -Concise, specific descriptions of how some aspect of the natural world is expected to behave in a certain situation Theory - ANSWER -Well-tested explanation that unifies a broad range of observations that has been throughly tested Bias - ANSWER -*A partiality that prevents objective consideration of an issue or situation* This can make scientists misinterpret data because they want to prove a certain point Peer Review - ANSWER -Checks by anonymous, independent experts where the experts look for any oversights, unfair influences, fraud, or mistakes in techniques or reasoning No, because science is always changing, and new evidence is always