8th Grade Sience Final Exam Study Guid- 2012

Moving an object over a distance using Force (W = F x d)
A push or pull (F = m x a)
Resistance to change in an objects motion
The resistance one surface or object encounters when moving
over another object
Newton's 1st Law
An object in motion stays in motion while an object at
rest stays at rest unless acted upon by an outside force.
Newton's 2nd Law
F = m x a. Force is equal to mass times acceleration
Newton's 3rd Law
For every action there is an equal and opposite reaction.
Rate at which an object moves (Speed = distance/time)
Speed in a given directionAcceleration
Rate of change in velocity
Law of conservation of Energy
Energy is not created nor destroyed but transferred from one form to another.
Know what Potential and Kinetic Energy are and how they are different.
Potential energy is stored energy - a car at the top of a hill Kinetic energy is energy of motion - a car moving down the hill
Know the 2 reasons why Earth has 4 seasons.
Tilt of Earth on its axis; Revolution of Earth around the Sun
Know which hemisphere (Northern or Southern) is receiving the most Sun during each of the 4 Seasons.
Spring, Summer, Autumn, and Winter
What causes us to see the moon in the night sky?
The sun reflects off the surface of the moon
What causes day and night?
Rotating of Earth on its axis
What is the difference between rotation and revolution? How long do each take?
Rotation is on an axis - 24 hours; Revolution is around the Sun - 365 1⁄4 days
List the Inner and Outer planets. What are the difference between the two groups?
Inner planets are closer to the Sun and are small and rocky. The inner planets include Mercury, Venus, Earth and Mars
Outer planets are farther from the Sun. Include Jupiter, Saturn, Uranus and Neptune; Pluto was considered an outer planet until recently. It differs from the other outer planets because it is rocky.
What is the difference between an asteroid, meteor and a meteorite?
Asteroid - large chunk of rock or metal that orbits the Sun Meteor - rock or metal that enters Earth's atmosphere Meteorite - piece of tock or metal that falls on a plant or moon's
What is the name of the first asteroid to be discovered?
Ceres in 1801
Define the following: comet, Kuiper belt, Oort Cloud, nucleus, ellipse, coma and tail.
Comets - lump of ice, frozen gas and dust that orbits the Sun
Kuiper Belt - a cloud of comets or comet-like material exist beyond the orbit of Neptune
Oort Cloud - a cloud of comets or comet-like material that may contain trillions of inactive comets that is located far beyond Pluto's orbit
Nucleus - a dirty ice ball at the head of a comet
Ellipse - the shape of a comets orbit Coma - gas cloud that surrounds the nucleus of a comet
Tail - long, ribbon-like trail of comet dust and gas
What are the three parts of the rock cycle?
Sedimentary, Igneous and Metamorphic - see #4 for details.
What is the difference between magma and lava?
Magma - molten rock inside Earth
Lava - Magma that reaches the Earth's surface
How are the 3 types are made?
Sedimentary - weathering, erosion, compacting and cementing
Igneous - crystallization of hot melted rocks or minerals (large crystals - cooled slowly; small - cooled quickly) Metamorphic - existing rock that is changed by heat and pressure
Which rock type occurs the most?
Sedimentary - makes up 75% of rocks at Earth's surface
Which rock type that contains fossils and why?
What are minerals?
Naturally occurring, inorganic solid formed from elements or compounds and having a definite chemical makeup and regular atomic structure They are classified by harness, color, luster, streak, cleavage/fracture. Be able to identify minerals using a chart and know how to read Mohs' hardness scale
What type of rock are each of the following: marble, obsidian, pumice, pyrite, halite, graphite, quartz, mica, granite, coquina, limestone, sandstone,
(m- metamorphic; I - igneous; s - sedimentary; Min - mineral)
Marble - M; obsidian - I; pumice - I; pyrite - Min; halite - S; graphite - Min; quartz - Min; Mica - Min; granite - I; Coquina - S; limestone - S; Sandstone - S
What is in limestone to make it react to HCl?
Calcium Carbonate
How are minerals classified?
Hardenss, luster, streak cleavage/fracture, color, special properties
(magnetism, acid test, etc)
What are the base pairs that make up DNA and do they match up?
Adenine pairs with Thymine; Cytosine pairs with Guanine
What is the definition of genetics
Study of Heredity
What is a Punnett Square? Be able to fill in a Punnett square from given information, give possible genotypes and be able to calculate the phenotype percentages.
A table used to predict genotype and phenotype of offspring.
What is the difference between hybrid (heterozygous) and purebred (homozygous)
Hybrid(Heterozygous) - Two different genes, Tt
Purebred (Homozygous) - Two of the same gene; TT or tt
What is a genotype? Phenotype?
Genotype - Gene combination for a trait: TT, Tt or tt Phenotype - Physical appearance of trait: Tall or short
What is the difference between incomplete dominance and codominance?
Incomplete dominance - the hybrid phenotype is a blend of the purebred phenotypes. Ex. Red - RR; white - rr; pink - Rr Co-dominance - the hybrid phenotype shows BOTH purebred phenotypes. Ex. Black - BB; white - bb; Black and white spots - Bb
Who is the "father of genetics" and how did he get started?
Gregor Mendel - an Austrian monk. He worked with pea plants
What is a karyotype? Be able to get information from looking at one.
Organized display of an organisms chromosomes
What are dominant and recessive traits?
Dominant trait (gene) - Gene whose trait always shows itself if present - will hide the recessive trait if paired Recessive trait (gene) - gene that is hidden if paired with a dominant gene. Can only appear if there are two recessive genes for the trait
What are chromosomes and genes? Where are they located?
Chromosome - cell part that determines what traits living things will have Gene - parts of a chromosome that control inherited traits These are found in the nucleus of cells