organisms Singapore American Compare and. recessive Describe how chromosomes. determining traits.

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1 Standard 1: Life Science 1 As a basis for understanding Life Science, Grade 8 students will develop the following knowledge, skills and understandings: 1.1 Students understand the principles of heredity and its related concepts A typical cell of any organism contains genetic instructions that specify its traits. Those traits may be modified by environmental influences Compare and contrast the life cycles and reproduction methods of sexual and asexual organisms Explain how sexual reproduction produces offspring that inherit half their genes from each parent, throughh a process called meiosis Determine how inherited traits can be influenced by one or more genes Create models to show that plant and animal cells contain many thousands of different genes and typicallyy have two copies of every gene Know the two copies (or alleles) of the gene may or may not be identical, and one may be dominant in determining the phenotype while the other is recessive Describe how cells divide to increase their numbers through a process of mitosis, which results in two daughter cells with identical sets of chromosomes Explain relationships between inherited and environmental factors in determining traits Articulate that DNA (deoxyribonucleic acid) is the genetic material of living organisms and is located in the chromosomes of each cell Model and interpret the structure of DNA to show how it encodes genetic information Evaluate the pros and cons of genetic engineering and its impact on society Demonstratee effective use of a compound microscope Students understand the structure and function of cells and organisms The anatomy and physiology of plants and animals illustrate the complementary nature of structure and function Know reproductive organs of the human female and male generate eggs and sperm and how sexual activity may lead to fertilization and pregnancy Compare and contrast the life cycles and reproduction methods of sexual and asexual organisms. Students understand relationships among organisms and their physical environment. Students understand biological evolution and the diversity of life. American, January 14, 2009

2 Standard 2: Physical Science 2 As a basis for understanding Physical Science, Grade 8 students will develop the following knowledge, skills and understandings: 2.1 Students understand the structure and properties of matter A substance has characteristic properties such as density, a boiling point, and solubility, all of whichh are independent of the amount of the sample. A mixture of substances often can be separated into the original substances using one or more of the characteristic properties Determine the identity of an unknown mixture of substances by analyzing their chemical reactions Use standardized procedures to determine the volume of gas produced in a reaction Demonstratee the effects of pressure on gases and explain the composition of gas in terms of individual particles in constant motion Experiment with matter in different phases to observe the expansion and contraction of particles Use balances to compare densities of solutions and to infer concentration Explain the process of dissolving Explain how to find the amount of solute needed to saturate a volume of solvent Describe the characteristics of a solution at the particle level. 2.2 Students understand chemical reactions Substances react chemically in characteristic ways with other substances to form new substances (compounds) with different characteristic properties. In chemical reactions, the total mass is conserved. Substances often are placed in categories or groups if they react in similar ways; metal is an example of such a group Observe and compare reactions while they occur and the residues left behind Explain that a reaction changes initial substances into new, different substances Use information in the periodic table to analyze substances in terms of their elemental composition Use chemical formulas and balanced chemical equations to represent chemical reactions Conduct a neutralization reaction to determine the effectiveness of an antacid Explain chemical reaction as a process in which atoms rearrange to form new substances Measure the volume of gas produced in a reaction to infer the concentrations of reactants Use water displacement to determine the volume of oxygen consumed during the oxidation of iron Chemical elements do not break down during normal laboratory reactions involving such treatments as heating, exposure to electric current, or reaction with acids. There are more than 100 known elements (90 of them naturally occurring) that combine in a multitude of ways to produce compounds, which account for the living and nonliving substances that we encounter. American, January 14, 2009

3 Explain that all common matter is made of elements Explain the structure and interactions of subatomic particles. 2.3 Students understand the sources and properties of energy Energy is a property of many substances and is associated with heat and the nature of a chemical. Heat moves in predictable ways, flowing from warmer objects to cooler ones, until both reach the same temperature. In most chemical reactions, energy is transferred into or out of a system Explain expansion and contraction in terms of kinetic energy Explain how a thermometer works Recognize mixing hot and cold water as an example of energy transfer Calculate energy transfer in calories Explain energy transfer in terms of change of particle kinetic energy resulting from collision Using ice, hot water, and flame to transfer heat to and from substances, observe phase change and explain phase in terms of the relationship of particles to one another in a substance Discuss phase change in terms of kinetic energy and energy transfer. 2.4 Students understand forces and motion The motion of an object can be described by its position, direction of motion, and speed. Motion can be measured and represented on a graph Observe and describe an object s motion in terms of change of position Explain how to use a reference point to determine the distance moved by an object Measure distance in standard metric units Conduct experiments to acquire distance and time data and to determine speed Explain speed in terms of distance and time Use speed graphs to determine head starts Transform narrative accounts of motion events into graphic representations Generate motion scenarios from graphic representations of motion events Explain the difference between displacement and distance Explain what a horizontal line on a speed graph represents An object that is not being subjected to a (net) force will continue to move at a constant speed Conduct simple investigations to demonstrate inertia of both stationary and moving masses Use a force scale to determine the force needed to stop cars traveling at different speeds. American, January 14, 2009

4 Use electronic Dot car data to calculate velocity and momentum Explain how inertia and momentum affect passenger safety in car crashes Explain and apply the interplay of force and time (impulse) and momentum in crashes If more than one force acts on an object along a straight line, then the forces will reinforce or cancel one another, depending on their direction and magnitude. Unbalanced forces will change the speed or direction of an object s motion Use equations to calculate acceleration, displacement, and velocity of rolling objects Identify and interpret graphs of accelerating motion and constant velocity Use tools (pushers, spring scales, and multimedia simulations) to apply force and investigate friction and motion Analyze illustrations of forces in motion Investigate force and motion using multimedia simulations Describe change of motion as a result of net force Determine the relationship between mass and the force of gravity, using spring scales Gather time and displacement data electronically to investigate the acceleration of gravity Explain gravity as a universal force Discuss Galileo s discovery of acceleration due to gravity Students understand waves and optics. Students understand electricity and magnetism. Standard 3: Earth and Space Science This standard does not apply. American, January 14, 2009

5 Standard 4: Nature of Sciencee 5 As a basis for understanding the nature of science as it relates to scientific knowledge, scientific inquiry, and scientificc enterprise and to addresscontent in the other standardss Grade 8 students will: 4.1 Students understand sciencee is a process used to solve problems. Scientificc progress is made by asking meaningful questions and conducting careful investigations Develop questions, design experiments and perform investigations Develop a question that can be tested by gatheringg quantitative and/ /or qualitative data Formulate a hypothesis Design an experiment to collect data that can be used to answer the question Identify variables in an experiment that could adversely affect the outcome Identify the independent and dependent variables as well as constants in an experiment Use a control to compare outcomes of an experiment Write a procedure that is sequenced and ordered Make observations for qualitative data collection Use measurement for quantitative data collection Organize data using tables, graphs, diagrams Make a prediction based on observations Communicate the steps and results from an investigation in written reports and oral presentations Analyze data to answer the initial question Revise experimental method if the question is not answered Compare the results with the hypothesis Display findings in a written report with visual support Formulate evidence based decisions Select and use appropriate tools and technology to perform tests, collect data, and display data Use Excel for graph display Formulate tables to organize data Use a variety of tools to collect data Use metric measurements of volume, distance, mass, force, density, and temperature to record quantitative data. American, January 14, 2009

6 Collaborate through sharing of data to achieve accurate conclusions Use a variety of print and electronic resourcess (including the World Wide Web) to collect information and evidence as part of a scientific presentation Identify appropriate material from World Wide Web, including databases Differentiate evidence from opinion Apply the correct procedure in writing a bibliography Use simulations, construct scale models, maps, and appropriately labeled diagrams object) Use coordinates to identify positions on a map Construct a 3 D model to demonstrate a process or action Draw and clearly label diagrams for information. Students understand the nature of scientificc knowledge Know that all scientific ideas are tentative and subject to change and improvement in principle, but for the most core ideas in science, there is much experimental and observational confirmation. Students understand scientific enterprise relates to ethics and ideas Show with evidence ethics associated with scientific study (potential subjects must be fully informed of the risks and benefits associated with research and their right to refuse to participate; potential subjects must be fully informed of possible risks to community or property) Explain by example that throughout history, many scientific innovators have had difficulty breaking though accepted ideas of their time to reach conclusions that are now considered to be common knowledge. Students understand the connections among science, global issues and sustainable solutions Identify sources of air, water and soil pollution Explain the impact of climate change and global warming Explain the role of genetics and human population dynamics Compare and contrast alternative energy resources. to communicate scientific knowledge and data (e. g. change in velocity of an American, January 14, 2009