Name: ____________________
7 th
Grade Science: Final Review Packet, 2012, Answer Key 
Purpose: Your final exam is cumulative, which means it covers material from the whole year.
This is not to torture you, it is to reinforce the main ideas, many of which you’ll need next year, and give you a chance to demonstrate that you meet all the standards. We’ll go over everything in this review packet together, and your exam questions will only come from this review packet.
If you pay attention in class & complete the packet assignments, you’ll be right as rain.
Suggestion: You can write your answers/notes in your notebook, or if you want, you can get a copy from homework online, save it to your own jump drive or home computer, put in a bunch of spaces and then print a copy you can write on as we go. 
General Science Methods:
Do you get the “big picture” about science? Do you understand the scientific method? Can you make observations, graph data, and draw conclusions about the data?
1. Define & give at least 1 example for each of the following: tree is on fire.
be correct). Example: That tree was hit by lightning.
2. What is an hypothesis? a. An educated guess about the answer to a question.
3. What is the purpose of graphs? To show data quickly
4. Describe the difference between variables (things that change) & constants (things that stay the same).
5. Which type of graph would you use for each of the following sets of data? a. Your height every year from birth to age 12. Change over time = line graph b. Your 2 nd
quarter grades for science, math, social studies & religion. Comparing quantities = bar graph
6. When is it ok to put things in your mouth during science lab? If Mrs. Maloney says ok.
7. What are the metric units for measuring the following? a. Length or distance meters (or mm, cm, km) i. How many mm in 1 cm? 10 volume i. How many ml in 1 liter?
1000 c. Mass i. How many milligrams in 1 gram? 1000
8. What is the difference between qualitative data (what something is like, described with words) and quantitative data (how much of something there is, described with numbers)
Earth & Space Science: Properties of water, the atmosphere, the earth, the solar system…
1. What is the difference between renewable (earth can regenerate in 100 years or less) & nonrenewable resources (takes the earth longer than 100 years to make more) ?
2. Which alternative energy resource is nonrenewable? nuclear
3. What are fossil fuels? Organic, Nonrenewable resources a. Give 2 examples of fossil fuels. Coal, oil, natural gas
4. Give an example of an inexhaustible resource. Wind, solar
5. What are alternative energy resources? Non-fossil fuels a. Give 2 examples of alternative energy resources. Wind, solar, geothermal, hydroelectric, biomass, nuclear.

6. Describe the advantages & disadvantages of each energy resource. a. Fossil fuels: + cheap & plentiful, - pollution & limited (non-renewable) b. Wind: + inexhaustible & clean, - not available everywhere all the time c. Solar: + inexhaustible & clean, - not available everywhere all the time d. Hydroelectric: + renewable, clean, - habitat loss, not available everywhere e. Geothermal: + renewable, - not available everywhere, can be expensive to start f. Biomass: + renewable, - pollution & possible smell g. Nuclear: + efficient & clean (when it works), - nonrenewable, radiation danger
7. Water covers most of the planet. It is necessary for life! Give an example of water in each of the 3 states. Solid (iceberg, snow), Liquid (ocean, rain, stream), Gas (fog, steam)
8. List 5 ways we use water (fresh or salt): Transportation (shipping), sanitation (cleaning), recreation (playing), irrigation (watering crops), hydration (drinking).
9. How much of the earth’s water is in oceans? Less than 20%, about 50%, or more than
80%?
10. Without fresh, clean water, life on earth would suffer. What are some ways water gets polluted? Name or describe at least 3. Runoff from farms, roadways, yards. Acid rain.
Pouring waste directly into the water supply (oil or soap into gutters, etc.) Fuel, trash, waste from boats.
11. What are 3 ways you can help to keep earth’s water supply clean? Apply fertilizers and pesticides according to package directions. Reclaim oil when servicing car/boat. Avoid pouring waste into street gutters. Conserve water supply by using resource wisely.
12. What are 2 things that can affect the density of water? Temperature & salinity
13. Sketch and label an example of the water cycle. Warm water rises (evaporation), cools
(condensation) and falls (precipitation).
14. FYI: water molecules stick together because of cohesion.
15. Convection currents fuel ocean currents, the weather, and movement of tectonic plates.
Describe and sketch a convection current. (see water cycle, below)
16. How does water change the shape of the land around it?
Erosion AND deposition.
17. Why is the windward side of a mountain wet, and the leeward side dry? As the air rises to go over the mountain, it cools, condenses, rains. By the time it reaches the leeward side, most of the moisture has precipitated out.
18. What happens to air pressure as you go up a mountain? It decreases. Why?
There is less air above you pressing down
19. The atmosphere is 78% Nitrogen, 21% Oxygen, and 1% trace gases .
20. The ozone layer protects us from: the sun’s harmful UV rays .

21. The first gasses got into Earth’s early atmosphere from erupting volcanoes.
22. FYI: The atmosphere keeps Earth at the right temperature to have liquid water somewhere on Earth at all times. This allows life to exist 
23. The sun is the ultimate cause of all weather because: it heats different surfaces of the earth unevenly. Temperature difference = density difference = movement.
24. Conduction, convection and radiation: a. Which is the transfer of energy in the form of RAYS? Radiation b. Which is the transfer of heat by the flow of heated material rising, cooling, sinking, etc.) convection c. Which is the transfer of energy between molecules that are touching?
Conduction
25. The temperature, humidity, wind and barometric pressure RIGHT NOW: weather
26. The boundary between 2 air masses: front
27. A measure of how much moisture is in the air: humidity
28. A measure of how much moisture is in the air, compared with how much moisture
COULD BE in the air at that temp & pressure: relative humidity
29. A large, swirling storm that form over warm, tropical water: hurricane
30. A person who studies the weather: meteorologist
31. FYI: when the pressure is high, the weather is dry!
Space Supplement
32. Name the planets in order from the sun out. Mercury, Venus, Earth, Mars, Jupiter,
Saturn, Uranus, Neptune
33. List the inner planets & what they have in common.
Mercury, Venus, Earth, Mars a. Small, rocky, relatively warm, close together, close to the sun
34. List the outer planets & what they have in common. Jupiter, Saturn, Uranus, Neptune a. Large, gaseous, cold, far apart & far from the sun
35. List the dwarf planets and describe where they are located. a. Ceres (largest asteroid in the asteroid belt) b. Pluto (elliptical orbit usually beyond Neptune) c. Eris (beyond Pluto in the Kuiper Belt) d. Makemake (kbo) e. Haumea (kbo)
36. What is the definition of ‘planet’ (how are planets different from dwarf planets) a. Spherical, orbit the sun (nothing else), orbit alone (cleared their path)

37. Where is the asteroid belt? Between Mars & Jupiter a. Where did the asteroid belt come from? Debris that might have formed a planet when the solar system formed except for the opposing gravities of Jupiter & the sun
38. The path the Earth travels around the sun: orbit.
39. FYI: the motion of the Earth around the sun is called revolution.
40. Day and night are caused by the Earth spinning on its axis. This spinning is called: rotation
41. Twice a year day and night are equal. These are called: equinoxes
42. When the earth is tilted as far toward the sun as possible, & we have the longest day of the year: Summer Solstice.
43. When the earth is tilted as far away from the sun as possible, & we have the shortest day: Winter Solstice
44. Seasons are a result of: the tilt of the earth on its axis
45. When the moon seems to be getting bigger: waxing
46. When the moon seems to be getting smaller: waning
47. When the moon seems to be a complete circle (one whole side is lit): full moon
48. FYI: The central, darkest part of the moon’s shadow is called the umbra.
49. The lighter part of the Moon’s shadow is called the: penumbra
50. The daily rise & fall of sea levels: tides
51. FYI: When the moon’s shadow appears on Earth’s surface it is a solar eclipse.
Life Science: This is basically ecology
1. What is a symbiotic relationship? Any close relationship b/t 2 species. a. Mutualism: Both species benefit . b. Parasitism: c. Commensalism: One species benefits, the other is unaffected.
2. Most producers get their energy from: the sun
3. Define “biotic” and “abiotic” Biotic = alive, abiotic = not alive.
4. Define & give an example of a carnivore (meat eater: wolf) , omnivore (eats meat & veggies: pigs) , & herbivore (plant eater: deer) .
5. What is the difference between an endotherm (regulates own body temp: people, dogs, dolphin) & an exotherm (can’t regulate own temperature: frogs, snakes) .
“climate”
7. What is an ecosystem? The living & nonliving things in an area

8. What is a habitat? The place where an organism’s needs are met
9. All the living things of the same species: population
10. FYI: A large region on Earth with a specific climate, physical features, plants and other organisms is called a BIOME.
11. What are 3 things that limit population size? Food, water, shelter, mates, predators
12. Give an example of a producer (plants: daisy, apple, oak) and a consumer (horse, robin) a. How do they interact in the food web? Producers make their own food
(photosynthesis or chemosynthesis) and Consumers eat food for energy.
13. What is the purpose of decomposers? Give an example. Decomposers break down other living things that have died (fungi like mushrooms)
14. Give an example of a predator/prey relationship. Wolf/rabbit. Eagle/fish.
a. What happens when the ratio of predators to prey is unbalanced? Too many predators wipes out prey organisms, and then the predators starve. Too many prey organisms, and they eat all the food then starve to death, then the predators starve, too.
15. What is biodiversity? Having a lot of different types of living things.
a. Why is biodiversity important? Increases resilience (ability to respond successfully to disease, disaster, etc.) b. What reduces biodiversity? Habitat loss or contamination, over-hunting.
16. The gradual change from one type of ecosystem to another (like a grassland to a forest): succession.
17. The gradual filling of a pond with sediment until it becomes a meadow: eutrophication
18. What are the 3 types of wetland? Swamp, marsh, bog
19. Wetlands are important because they help reduce flooding and erosion. Explain how they do this. Roots hold soil in place, reducing erosion, and absorb extra water to release slowly over time, reducing flooding.
20. FYI: every living thing respirates.
21. What is the difference between organic & inorganic? Organic: alive (or used to be).
Inorganic (never alive) a. Give an example of each material: organic: puppy, pickle, leaf. Inorganic: rock, rain, sand
22. What are 3 ways you can help keep the environment clean? Reduce, reuse, recycle.
Conserve energy. Walk or carpool. Be a smart consumer.

23. Why would you want to keep the environment clean? This is the only planet we have, and we need clean air, water and soil in order to survive.
24. What is the difference between habitat conservation ( keeping a healthy habitat healthy) and habitat restoration (bringing a damaged habitat back to good health).
Physical Science:
1. Isaac Newton is known for his 3 laws of motion. a. Newton’s first law (Inertia) states that: Bodies at rest stay at rest until moved, bodies in motion stay in motion until stopped.
nd
law is summed up as what equation? F = ma c. Netwon’s rd
law is that for every force there is an equal & opposite force .
2. FYI: if the forces acting on an object are balanced (zero), the object will not move.
Sooooo, if the net forces are unbalanced (not zero) the object will move 
3. The formula for work is: work = (force)(distance) a. The unit for work is: Joules
4. You should also be able to solve for force = (mass)(acceleration) a. The unit for force is: Newtons
5. FYI: The formula for speed is distance/time. is and direction ?
7. What 2 things need to be present in order for “work” to be done? Force & motion in the same direction.
a. The unit for work is: Joules (still. The answer hasn’t changed since #3)
8. Compare & contrast potential & kinetic energy. Potential energy is stored energy.
Kinetic energy is energy in motion.
9. What is the difference between mass & weight? Mass is amount of matter. Weight is gravity acting on mass.
a. So, if you were to go to the moon, which would change? Weight!
10. FYI: a force is a push or a pull
11. FYI: there is always fiction
12. Name the 6 simple machines. Lever, pulley, inclined plane, wedge, screw, wheel & axle
13. Machines reduce your effort force by increasing the distance over which work is done .
14. FYI: increasing mass increases inertia.
15. What is the difference between distance and displacement? Give an example of each.
Distance is the length traveled. Displacement is the difference b/t start & stop point, measured in a straight line.

16. FYI: A horizontal row on the Periodic Table of Elements is called a PERIOD.
17. FYI: Each column on the Periodic Table contains Elements with similar chemical properties. a. Column 1: Alkali Metals b. Column 2: Alkaline Earth Metals c. Column 7: Halogens d. Column 8: Noble Gases
18. Metals: shiny (lusterous), malleable (can be hammered into sheets), ductile (can be pulled into wire), and good conductors of electricity.
19. Metalloids contain properties of: both metals & nonmetals
20. The most common element in the universe is: hydrogen
21. The little box on a Periodic Table contains what information? Name of element, symbol of element, atomic number, state of matter
22. What is the difference between chemical (something new created, can’t be reversed) and physical change (no new substance created, can often be reversed, change of state like melting ice).
23. What is the difference between a substance (elements and compounds, can’t be reduced and keep their properties ) and a mixture (elements not chemically bonded together, homogenous or heterogenous, like a bowl of Lucky Charms with different shapes in the same bowl )
24. Energy is: the ability to do work. The ability to cause change.
25. Energy released from the nucleus of an atom is called: nuclear energy.