Ohio Achievement Assessment Review in

ScienceTopics Identified on the

Practice Test as,“I Need To Review!”

Measurement

• Mass is measured by a triple beam balance.

• Volume is measured using a graduated cylinder or the formula L x W x H (for a solid rectangular object).

• Density is calculated by Mass / Volume.

• Weight is a measurement of gravity’s effect on mass; can change based on the amount of gravity.

Changes to Matter

• Chemical changes alter the things in the reaction so “new stuff” is created; can’t be reversed easily (ex: burning, rusting).

• Physical changes change the appearance, but not the substances; can easily be reversed (ex: state of matter, shape).

• During any reaction, mass isn’t created or destroyed. The amount of mass always stays the same. That’s called the law of conservation of matter.

Motion

• Motion is defined as changing position over time.

• Change in motion occurs because forces acting on the object are unbalanced. When forces are balanced, there is no change to an object’s motion (remember the tug-of-war examples?).

• Speed is one way to measure motion, and is distance / time (think miles / hour).

Balanced & Unbalanced Forces

Balanced = Motion Doesn’t Change

Unbalanced = Motion Changes

Fossil Fuels

• Fossil fuels form from the fossilized remains of dead organisms (most likely lived in a swamp or marsh when alive).

• We burn fossil fuels to generate energy. This energy is consumed as electricity, gas that cooks food & heats our house, etc.

• Fossil fuels are not renewable – there is a certain amount of them on Earth and once they are gone, they are gone.

• Examples are… gasoline, oil, natural gas, coal.

Renewable Resources

• There is a push to develop renewable sources of energy.

• Renewable resources are usually less damaging to the environment.

• Examples: solar (sun), hydro-electric (energy from moving water), geothermal, nuclear, wind

• These forms of energy have other issues that limit their wide-spread use, the biggest being cost to harness the energy and means to store energy for later use.

Energy Consumption

Think… • Would you increase or decrease your energy

usage if you turned up your air conditioning?

• What if you turned your heat up?

Energy Consumption

Think… • Would you increase or decrease your energy usage if

you turned up your air conditioning?(If you turned up your air conditioning, you would save energy so it wouldn’t have to work so hard to bring down the temperature)

• What if you turned your heat up?(If you turned your heat up, you would increase your energy usage as it would work harder to maintain a higher temperature)

Earth’s Motion

• The Earth rotates (spins – causes day/night) and revolves (makes an orbit – causes years).

• Seasons on Earth are caused by the tilt of the Earth as it moves around the sun; indirect light hits during winter (cool) & direct light hits during summer (hot).

• The northern & southern hemispheres have seasons exactly opposite of one another.

Earth’s Motion

Weather

• Weather moves from west to east in the United States.• Low pressure = cloudy, chance of precipitation; High

pressure = clear skiesThink… there is high pressure on Mother Nature for nice days!

• Cold fronts (blue, look like icicles) bring cooler air; Warm fronts (red, look like suns rising) bring warmer air; Stationary fronts (alternating suns & icicles) mean the air isn’t moving too much (not a lot of change)

Weather Map Symbols

Here are the “basic” symbols to understand. I have blocked

some with these boxes, as they contain info that is more than

you really need to know.

Clouds

Cells• Organelles are parts of the cell:– Nucleus = brain– Mitochondria = “mighty” creates energy– ER (Endoplasmic reticulum) = transports messages (like the

ambulance transports to the ER)– Vacuoles = store water & food– Ribosomes = “ribs” store protein– Chloroplasts = only in plants… do photosynthesis– Cell membrane = lets in & out things from the cell– Cell wall = provides structure to plant cells– Cytoplasm = holds everything in place

Cells

• Plant cells are different from animal cells because they are usually more organized, have a cell wall, and may contain chloroplasts.

• Animal cells are more free-formed shape, less organized, and contain smaller vacuoles.

Moon Cycle

• The same side of the moon is always being “lit” by the sun.

• When the moon is in between the sun & Earth, we can’t see the lit side (new moon).

• When the Earth is between the sun & the moon, we can see the entire lit side (full moon).

• The above statements are true, unless there is an eclipse.

• The moon changes its appearance in the sky because of its change in position relative to the Earth & the sun.

Moon Cycle

Organisms Interact with One Another

• Symbiosis or Symbiotic Relationships:–Parasitic relationship = one organism

benefits & another is harmed.–Mutualism relationship = both organisms

benefit from the relationship.–Commensalism = one organism benefits

and the other isn’t affected.

The Rock Cycle

• Igneous rocks form when magma/lava cools (near volcanoes, think “ignite”)

• Sedimentary rocks for when little “bits” of “stuff” (called sediments) solidify to become rock (usually near/under water)

• Metamorphic rocks form when a rock is exposed to heat & pressure & changes (think “morphs”) into a new, different rock

• Based on the conditions, rocks are constantly changing form… that’s the rock cycle!

The Rock Cycle

Weathering & Erosion

• Weathering & erosion is a process that breaks down rocks of Earth’s surface (weathering), transferring sediments to other places (erosion)

• Deposition is the building up of sediments

Plate Boundaries

• Convergent (plates collide) creates subduction zones (trenches), tall mountains, volcanoes, earthquakes – crust is destroyed

• Divergent (plates pull apart) creates sea-floor spreading, ridges, rifts, small mountains, small volcanoes, earthquakes – crust is created

• Transform (plates slide past) creates earthquakes

Plate Boundaries

• Potential energy is stored (has the “potential” but isn’t showing it)

• Kinetic energy is the energy of motion

• These two are exactly opposite – when one is high, the other is low

Energy

Types of Energy

• Examples: electrical, mechanical, thermal, radiant, nuclear, acoustic

• When energy changes from one form to another, the total amount of energy stays the same – called the Law of Conservation of Energy

Tides

• The moon controls the tides because it is closer to Earth (compared to the Sun, which has more gravitational pull)

• Tides are highest when the sun & moon work together to pull on Earth’s water (spring tide)

Experimentation

• When developing an experiment, the controls are the parts that stay the same between all of your trials.

• The independent variable is what you deliberately change to see what will happen.

• The dependent variables are the effects of the independent variable that you observe as a result of the change you made.

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Experimentation

• Example: You decide to see what kind fertilizer makes a plant grow the tallest.

• Controls = amount of sunlight, water, fertilizer given, temperature of plants; “What do I keep the same?”

• Independent variable = different kinds of fertilizer; “What did I change?”

• Dependent variable = height of the plants, possibly the health of the plans that is different because of the different kinds of fertilizers used; “What do I observe?”

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Waves

• Waves transfer energy, not matter.• Examples of waves: earthquake/seismic,

water, light, sound• Some waves need a medium, or something

to travel through (like sound, seismic) and some don’t (like light)

• Waves cause energy to spread in all directions from the source.

Eclipses• Eclipses occur when the light from one celestial body is

blocked by another:

Lunar eclipse = the moon’s light is blocked

Solar eclipse = the sun’s light is blocked