8th Grade Science Study Guide 1 - Mapleschools
8th Grade Science Study GuideEarth & SpaceScienceThe Earth rotates on its axis. It takes 24 hours for the Earthto make one complete rotation (360 ). This makes onewhole day.The Earth revolves around the sun. When the Earth makesone complete trip around the sun it has been one completeyear.Seasons on Earth happen because the Earth tilts on its axisas it revolves around the sun. This tilt causes different partsof the Earth to be exposed to the sun’s most direct rays.1
The sun’s direct rays are the warmest and hit the Earth nearthe equator.2
Solar eclipse- occurs when the moon either partially or completelyblocks the sun from the Earth’s view.From Earth, as a solar eclipse begins, it looks like the sun has a bitetaken out of it.SunMoon advancing in front of sun casting shadowon Earth.Lunar eclipse- occurs when the Earth blocks our view of the moon.A lunar eclipse can only occur during a full moon.3
Why does the Earth and other planets in our solar system revolvearound the sun? Gravitational force is the reason. Newton proposed the Law of Universal Gravitation that saysbetween any two objects there is attraction (gravity) that isproportional to the masses of the objects and the distances betweenthem.This means that the more massive an object is, it has a strongerpull of gravity on the objects that are less massive than itself. Oursun is more massive than the planets so they all revolve around thesun.Our planet Earth is more massive than our moon so this is why themoon revolves around our Earth. Although objects that are lessmassive revolve around more massive objects, these less massiveobjects still give a pull on the more massive planet. This is why wehave tidal waves. The moon has a strong enough gravity to pullwater from oceans towards it, creating disturbances in the water.4
Some tools to study space are:Telescopes- with optical telescopes, astronomers see closer theobjects in outer space such as moons, planets, galaxies.Spaceship- allows astronauts to travel to close planets, our moon &into outer space to collect data, samples and experience first hand theconditions in space.Satellites- Are used to transmit signals from outer space such aspictures, topographic maps. Just like cell phone satellites allow oursignals to travel from place to place.Probes- are sent by scientists to collect data on far away planets thathumans can never get to. Probes send data back by signals & someeven retrieve samples from planets.Sample question- choose 2 tools astronomers use & listtwo pros & cons of each.TelescopesPros: Can see closer the object you are looking at. Cheaper & safer than sending a spacecraft toouterspace.Cons: telescopes can only help you see closer, theycannot take samples or conduct experiments. It has to be a clear night & little or no lightpollution to use telescopes properly.5
SpacecraftPros: Can allow astronauts to conduct experimentsin outer space and take samples of the moon. Can allow humans to explore & experiencebeing in space.Cons: It’s very expensive to run a space program. There are always risks when sending humansinto space – it’s dangerous.Our solar system- the Sun, our Earth and the 8 othersbelong to the Milky Way Galaxy. Some scientists arecurious to know if there are other solar systems out theirwhich support life like ours does.There are 3 different kinds of galaxies. Galaxies are characterized bytheir shape.1). Spiral 2). Eliptical 3). Irregular 6
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Asteroids, Meteors & CometsAsteroids- are very large rocky objects that revolve around the sun ina common place called the Asteroid Belt. The Asteroid Belt liesbetween the orbits of Mars and Jupiter and contains millions ofasteroids. They range in size from a pebble to having a diameter ofalmost 600miles.Comets- are made up of ice, dust and rocks. This is why they arecalled “dirty snowballs”. Most travel in elliptical orbits around thesun due to the sun’s great gravitational pull on them. Comets sometimes enter our solar system from far off in space and if they get closeenough to the sun they form a tail which is vapor from the icemelting.Meteoroids- are small chunks of rock that range in size from a grainof sand to a softball. They break off from comets and asteroids andcan enter Earth’s atmosphere. When meteoroids enter our atmospherethey are called meteors or shooting stars. We see them glowingbecause they are traveling at great speeds and friction occurs betweenthem and our atmosphere. This creates great heat causing them toglow. If a meteor hits the Earth’s surface it is called a meteorite.When objects such as meteors, comets and asteroids come closeenough to a planet, that planet’s gravity can pull that objecttowards it.8
Since planets and objects in space are so far away from each other,scientists created the unit of light years which is the distance lighttravels in one year (9.5 trillion kilometers). Kilometers or miles arejust too small.It’s like trying to measure a trip you & your family are takingout of state in inches. The units are too small.Earth ScienceCross-Section of Earthconvectioncurrentscorecrustmantle-molten liquidrock.The crust of the Earth, make up the plates that float on the liquidmagma of the mantle. The heat of the Earth creates convectioncurrents (shown w/ arrows) that slowly move magma in the mantlelayer. This movement causes crustal plates to shift which is calledplate tectonics.9
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Volcanoes also occur when plates go over a hot spot in themantle.An oceanic trench occurs where a dense thin oceanic plategoes underneath a thick less dense continental plate.The Rock CycleWhen magma leaves the mantle of the Earth, it createsigneous rocks. Igneous rocks are cooled lava.Weathering such as water, wind, rain, freezing and meltingcauses these rocks to breakdown or erode.11
The pieces that are taken away get laid down (deposited) onthe ground or on the bottom of rivers. In time, there are manylayers much like the layers of a cake. This is calleddeposition. These particles and pieces of rock are calledsediments and they can get cemented together by pressureover time to become sedimentary rocks.Both Igneous & Sedimentary rocks can change or“morph” into a new type of rock by extreme heat & pressurewhen they are close to the Earth’s mantle. This new type ofrock is called a Metamorphic rock.Rocks continuously go through these different changes.This is called the Rock Cycle.http://www.naturescience.org/Rxcycle.htm12
When sedimentary layers are laid down, the youngestlayer is always on top. These rock layers can fold & faultcausing the younger layers to be put below older layers.We can see how rock layers can fold & fault causing theyounger layers to be put under older layers as shownbelow.A foldA fault13
PhysicalScienceReference point & motionObject in motionReference pointObjects are in motion when they change their position over time. Inorder to see an object in motion (moving), we must see it in relation toan object that is standing still such as this building. This object thatstands still is called the reference point.Balanced & Unbalanced ForcesA balanced force is when the forces acting on an object(opposing forces) are equal causing that object to stand still.ex. If you hold up a ball with your hand, and the ball isstanding still, the force of gravity and the weight of theball equals the force you are applying to keep it still.14
Another example- If two sides of a tug-o-war are equal inforce, the rope will not move. This is a balanced force. Unbalanced- means that these two opposing forces arenot equal.If the force of gravity is greater than the force youapply to the ball then it will cause the ball to push yourhand down.The side of the rope that has a greater force willcause the side with the weaker force to get pulled towardthem. This is an unbalanced force.Energy can be transferred through waves. Waves are aflow of energy such as light, sound, radio and waterwaves.When sound travels through the air, it is actuallytraveling along air molecules. These molecules bump intothe next set of air molecules similar to dominoes thattransfer energy to the near by domino piece.15
Similarly, when you drop a pebble into a pond, it causesthe water molecules next to the pebble to vibrate or bumpnearby water molecules. This causes a spread of ripplesthroughout the pond. Here, energy spreads from theoriginal source.Forces & MotionA force is a push or pull on something.If a skater goes down off a ramp, what forces are actingon the board?Friction happens when objects rub against each other such aswheels and the ramp.Gravity happens to any object on Earth. Gravity pushes downon a person & the board.The ramp has a force since it is holding up the person andboard.Potential energy- Is stored energy. When the skater is atthe top of the ramp, he/she has potential energy because16
as soon as they reach the edge they are going down!Kinetic Energy- Is energy in motion. The skater goingdown as in the picture is experiencing kinetic energy. Thepotential energy from being on top of the ramp got convertedinto this kinetic energy.Moh’s hardness scale- categorizes the hardness of minerals. Hardnessis the resistance of a mineral to being scratched. These minerals arenumbered 1thru 10. 1 being the softest mineral on Earth & 10 beingthe hardest meaning nothing else can scratch a #10.Moh’s scaleSoftest Talc 1Gypsum 2Calcite 3Fluorite 4Apatite 5Feldspar 6Quartz 7Topaz 8Corundum 9Diamond 10 HardestIf a mineral has a higher # than another mineral, then the higher # willscratch the lower one.ex. Quartz will scratch Feldspar 7›6 and a diamond can scratchanything. This does not mean a diamond is the strongest substancebecause a hammer can smash a diamond. Being the hardest mineralon Earth means it can scratch any other material. REMEMBER:Higher #’s scratch lower #’s.17
Environmental science issues:Fossil layers of the Earth are our source of fossil fuels. Theseorganisms turned into carbon which we use as fuel. They includegasoline, oil and coal. Fossil fuels are considered nonrenewableresources because we can never replace or renew them. They tookmillions of years to form!Renewable resources however can be replaced and renewed.Sunlight, water power,wind, wood, crops are all renewable resources.Sunlight never runs out.Crops & wood can be constantly grown.The downside to fossil fuels is one: They will run out one day soon.& two: They cause GLOBAL WARMING!!!!!!18
When we protect our resources (items we use from the Earth) &nature, this is called conservation.How can we conserve resources? recycle car pool riding a bicycle instead of driving. use public transportation. turn off water and electricity when were not using them.For the OAT, we will have to be able to trace the paths of energythrough a system.ex. What energy transformations occur for a tree getting energy fromthe sun? Solar energy(or light energy)converts to chemical energy(during photosynthesis).19
ex. What kind of energy transformations occur inside an mp3 playeras someone is listening to their music? chemical energystored in battery gets convertedto electrical energythat powers the playerwhich becomessound energyLife SciencePhotosynthesis & RespirationPhotosynthesis- occurs when plants convert light energy intochemical energy. This requires them to take in Carbon dioxide (CO2)and release oxygen into the air.CO2OxygenHumans are opposite, we respirate.Respiration- Animals & humans take in oxygen & breath out carbondioxide (CO2).oxygenCO220
Cells: The smallest structural & functional unit of an organism. Theycarry out life processes. New cells come from existing cells.Inside a cell are smaller structure that carry out processes for the cell.They are called organelles.Here is a list of organelles & their functions, found in plants &animals. Students should be familiar with these.OrganelleFunctionNucleusControl center of cell & contains DNA.RibosomeMakes proteins.LysosomesDigests food particles, wastes & foreigninvaders.MitochondriaProduces energy. (Powerhouse).EndoplasmicReticulumTransports materials throughout cell.Golgi Complex(apparatus or body)Processes & packages proteins for shipmentout of cell.VacuoleStores water, food & water.CytoplasmA fluid that fills a cell & surrounds theorganelles in a eukaryote.21
Sometimes different organisms can interact together in a unique waywhere at least one organism benefits from living with the other. Thisis called symbiosis.There are 3 types of symbiosis.1. Mutualism- when both organisms benefit from each other.ex. A bee & a flower. The bee pollinates the flower ensuring theflowers survival in the next generation and the flower provides thebee with nector- the bee’s food.2. Commensalism- When only one organism benefits from therelationship and the other is not harmed or helped.ex. A bird & its nest up in a tree benefits the bird giving it protectionand the tree is not helped or harmed by the bird living there.22
1. Parasitism- When one organism benefits and the other is harmed.The parasite harms the host.ex. A flea on a dog benefits because it is sucking blood which is itsfood. The dog (the host) is being harmed because his blood is takenaway.ReproductionSexual reproduction- involves producing offspring from twoparents. Here, DNA from each parent combines together to createDNA of the offspring. This creates variety.23
By chance, nature will favor certain genetictraits (characteristics) over others.For example- Millions of years ago, some giraffes were bornwith short necks & others were born with longer necks. When lowgrass & scrubs (food for giraffes) became scarce the giraffes with thelonger necks were able to reach the leaves in the higher trees tosurvive.The short necks could not reach the food so they did not survive. Thelong necks survived so their genes for long necks were passed downto their offspring. Nature happened to favor the long neck variation,while eliminating the gene for short necks. This long neck giraffedeveloped gradually over many generations of giraffe families.Conditions in nature favor certain genes over others. In this examplebody type.Just as this animal adapted to a change, another change couldcome about and not favor long necks, for example if all the tall treeswere eaten or killed and the long necks couldn’t bring their longnecks that low to the ground. Remember that changes can occuranytime, either favoring an animals particular characteristics orcausing that animal to become extinct.Asexual reproduction- involves reproduction from only one parent.Here, the DNA of the offspring is identical to the parent.Many organisms reproduce this way including bacteria, fungi someplants & animals.24
Science & TechnologyWhat we know about science has comefrom people from all over the world. Scientists from the past,such as Egyptians, Chinese, & Romans made discoveries andlater scientists build on this older knowledge. We can say thattoday’s scientists are standing on the shoulders of previouspeople’s work.Technology are tools created by scientists that allow us to dothings we couldn’t do on our own. We cannot see the surfaceof the moon without a telescope, or see through skin andmuscle to see our bones.Scientists are working today on new discoveries andtechnologies.In the years to come, scientists will create things we onlydreamed of. Maybe you’ve got an idea? Study in school,keep your dreams alive and you’ll have all the tools you needto be a scientist of the future!25
Some places of the world have more opportunities thanothers to use technological advances. For example, inCleveland, one could get the best surgery to get their heartreplaced. If you lived in an undeveloped area of the worldsuch as a rainforest, you would most likely not go to thehospital.Politics also determines how technology gets used. Wehave the technology to make cars that do not create pollutionthat today’s cars make. Unfortunately, some people caremore about money than the health of the planet and itspeople.If you were the president of a country, could you designa way to produce energy that does not pollute the air? What ifyour country did not have much money or materials? If yourcountry’s scientists came together and gave you ideas, wouldyou be able to decide if these solutions would work or not?These are serious questions about science that affecteveryone.26
Scientific InquiryThis area of science deals with how we ask questions or“inquire” about things.Say you wanted to find out what kids in your schoollike the most: skateboarding or rollerblading? When youwent to math class you asked 5 people that sat near you and 3said they like skateboarding better.Does this give you an accurate answer of what yourschool likes best? No, because 5 people are not enough togive you an accurate inventory of your whole school. If youasked every student in each of your classes that would bemore accurate. Scientific investigations need a large sampleto be tested.If you tested to see if fertilizer helps a tomato plant grow youwould treat more than just one tomato plant with fertilizerbecause there could be something wrong with a plant toinfluence the outcomeyou might think it was the fertilizer when it was somethingabout the plant you couldn’t see. Also some plants might geteaten by insects so you want enough samples.How do we know the fertilizer works? We need to use acontrol. A control is an untreated sample that we use tocompare the treated sample to. In this case a tomato plantwith all the same conditions (same sunlight & water) exceptno fertilizers.27
Be able to read and interpret graphs.H o b b ie s a t M ilk o v it c h M id d le S c h o o ls u r v e y o f e n t ir e s c h o o lW a tc h tv16%V id e ogam es28%V id e o g a m e sO u td o o rA c ti v i ti e s56%O u td o o r A c ti v i ti e sW a tc h tvLooking at the graph above, which hobby is the favorite to moststudents at Milkovich?Do we have the right tools & safety equipment for the job?Know scientific instruments, their purposes and how to inquireabout science with them.28
Ex. Be able to figure out the volume of an object using a graduatedcylinder.The volume of an object is the amount of space it takes up. Abowling ball takes the same amount of space as a beach ball that isthe same size as the bowling ball. The only difference is the bowlingball has a greater density.Density the amount of matter taking up that space.The marble displaced the water from 30ml to 40ml so the marble’svolume is 10ml.Some experiments involve dangerous chemicals and hazards.If you are working on an experiment like this, your teacherwill make sure you understand proper procedures in the eventof an accident. What do you do if you spill an acid on yourskin or in your eyes? Be sure to know how to respond inthese situations.29
Math skillsShow off your math skills on the science OAT.Below are math test scores (in %) of 9 students.757679808787879198Find mean score- or average score. To do this you add all scorestogether and divide by how many scores there are (9).mean75 76 79 80 87 87 87 91 98 760/9 84.4Find median score- or middle score. We find median by choosingthe score that is exactly in the middle of the numbers when theyare in order from lowest to highest. 87 has 4 scores to the left(lower) and 4 to the right (higher).75 76798087878791If you have a list of numbers that is even such as these 685878991939897Divide the #’s evenly as shown above. The median is between 89& 91 so you add these two middle numbers together and divide by2 to find the # exactly between 89 & 91.89 91 180median180/2 90Finding mode – This is the # that appears most frequently.757679808787 appears 3 times. This is the87879198mode30
Scientific Ways of KnowingInference- is an attempt to explain or speculate about yourobservations. This is something you think might happen, ishappening given what you observe. It may or may not be tr
8th Grade Science Study Guide The Earth rotates on its axis. It takes 24 hours for the Earth to make one complete rotation (360 ). This makes one whole day. The Earth revolves around the sun. When the Earth makes one complete trip around the sun it has been one complete year. Seasons on Earth happen because the Earth tilts on its axis
Teacher of Grade 7 Maths What do you know about a student in your class? . Grade 7 Maths. University Grade 12 Grade 11 Grade 10 Grade 9 Grade 8 Grade 7 Grade 6 Grade 5 Grade 4 Grade 3 Grade 2 Grade 1 Primary. University Grade 12 Grade 11 Grade 10 Grade 9 Grade 8 Grade 7 Grade 6 Grade 5 . Learning Skill
Math Course Progression 7th Grade Math 6th Grade Math 5th Grade Math 8th Grade Math Algebra I ELEMENTARY 6th Grade Year 7th Grade Year 8th Grade Year Algebra I 9 th Grade Year Honors 7th Grade Adv. Math 6th Grade Adv. Math 5th Grade Math 6th Grade Year 7th Grade Year 8th Grade Year th Grade Year ELEMENTARY Geome
NMPED 8th Grade Science EOC Blueprint Project Management by 2 Purpose Statement 8th Grade Science The 8th Grade Science End-of-Course (EOC) exam is intended to measure student proficiency of the New Mexico Science Standards. This course-level exam is provided to all students who have completed 8th Grade Science or related courses. This exam can be given for the following STARS course codes:
End of the Year Celebrations June 3rd: 8th Grade Breakfast (OLA Gym; 8:30 AM); Grades 1-4 Field Trip to the Bronx Zoo June 4th: 8th Grade Dinner-Dance (7 PM) June 5th: Altar Server/SCOLA Trip June 6th: 8th Grade Trip to Philadelphia June 7th: 8th Grade Honors (Morning Announcements, 8:05 AM); Graduation Mass (OLA Church 8:30 AM) June 8th: 8th Grade Graduation (OLA Church, 1 PM)
ICCSD SS Reading 2014 ICCSD SS Reading 2015 Natl SS Reading. ICCSD Academic Achievement Report April 2016 6 0 50 100 150 200 250 300 350 3rd grade 4th grade 5th grade 6th grade 7th grade 8th grade 9th grade 10th . 7th grade 8th grade 9th grade 10th grade 11th grade e Grade ICCSD and Natio
Grade 4 NJSLA-ELA were used to create the Grade 5 ELA Start Strong Assessment. Table 1 illustrates these alignments. Table 1: Grade and Content Alignment . Content Area Grade/Course in School Year 2021 – 2022 Content of the Assessment ELA Grade 4 Grade 5 Grade 6 Grade 7 Grade 8 Grade 9 Grade 10 Grade 3 Grade 4 Grade 5 Grade 6 Grade 7 Grade 8
8th Grade Summer Math Packet Dear Future 8th Grader, This summer math packet is designed to help you keep your math skills strong before returning to 8th grade in the fall. We want you to feel confident on the following skills and problems when you begin 8th grade. If you get to a problem you are confused on, here are some ideas to help:
Math: 5/1, 5/2 Our 8th grade students will take: Science Performance Test: 5/22 Science Written Test: 6/3 Our 8th grade Algebra I students will take the Algebra I Regents Exam on June 19th, 12:00-3:00pm. All 8th grade Algebra I students will be exempt from the 8th grade math assessment. Character Trait of the Month Trustworthiness
