grade 7 science unit 1

Question Answer
what is matter? anything that takes up space and has mass
what is matter made up of? matter is made up of tiny, vibrating particles
what are the 5 main points of the particle theory? all matter is made up of tiny particles that:
have empty spaces between them
are always moving(vibrating)
move faster and spread farther apart when heated
particles attract each other
what is a mechanical mixture? a mixture with diffrent parts that you can see since the particles are divided unevenly
what is a solution? a mixture that looks like a single pure substance, but is a uniform mixture of 2 or more pure substances since the particles are divided evenly
what is a solute? the part of the solution that dissolves into a solvent
what is a solvent? the part of a solution into which the solute(s) dissolve
what is concentration? a solution with a large number of solute particles in a given volume of solution
what is solubility? is a measure of how much solute can dissolve into a certain solvent to form a saturated solution
what makes a substance pure? a pure substance has only one kind of particle
what does dissolve mean? to mix one type of matter into another type of matter to form a solution
what is the universal solvent? why is it known as the universal solvent? water becuase dissolves more solutes than any other solvent
what does dilute mean? a dilute solution is a solution with a small amount of solute particles
what is the formula for concentration? mass of solute(grams)/ 100mL of solution
what is the formula for solubility? maximum amount of solute dissolved/ 100mL of solvent
what is the sequence to figure out concentration or solubility? GRASS (given, required, analysis, solution, statement)

Immune Attack

Term Definition
Blood vessels Carries blood throughout the body
Salmonella Strain of bacteria that can enter the human system through contaminated water or food.
Macrophage A type of white blood cell that eats bacteria.
Neutrophils Fast moving immune cells and are the front soldiers of the immune system. They kill bacteria before dying from exertion.
T/B cells T cells and B cells are the commando units of the immune system. They can defeat invaders that leave macrophages and neutrophils confused and helpless. But each is programmed to go after only a specific type of invasion.

Sustaining Biodiversity: The Species Approach

Question Answer
Fill in the blank: Human activities deplete biodiversity and destroy many specie's natural ___________ habitats
The extinction of many species over a short period of time is called what? mass extinction
A humpback chub is NOT an example of an endangered or threatened species, true or false? false
Between endangered or threatened species, which one is still abundant in its natural range? threatened
Fill in the blank: Species play an important role in earth's _________ _________ natural capital
Non-native species can also disrupt ecosystems, true or false? true
Global warming is harming _______ bears in their fight against extinction polar
Do international species help to protect endangered species, yes or no? yes
Seeds are refrigerated here so that certain plant species are well preserved and continually grown, where is this? gene bank
The call for humans to take great precaution to prevent extinction for animals, even if it may not be proven that it directly relates to them is called what? The Precautionary Principle

study for quiz

Question Answer
A fixed place from which location and direction can be described is a? reference point
The reference points used when describing direction and location on the Earth are the? North and South Poles
The imaginary line that runs from the North Pole to the South Pole is called the? axis
What are the directions north, south, east and west called? cardinal
Which of the following shows which direction is north? compass
Which kind of pole is true north? a magnetic pole

Section 1: Electric Charge and Static Electricity

Question Answer
What is the law of electric charges? The law that states that like charges repel, or push away, and opposites attract.
What is electric force? The force of attraction or repulsion on a charged particle that is due to an electric field.
What is an electric field? The space around a charged object in which another charged object experiences an electric force.
What is a an electrical conductor? A material in which charges can move freely.
What is an electrical insulator? A material in which cannot move freely.
What is static electricity? Electric charge at rest; generally produced by friction or induction.
What is electric discharge? The release of electricity stored in a source.
The size of the electric force between two objects depends on _____________ and __________________. The size of the charges exerting the force and the distance between the objects.
Objects may become charged by ___________, ___________, or ______________. friction, conduction, or induction.
What are the two types of charged particles in atoms? protons (+) and electrons (-)
What can you do with an electroscope? To detect whether an object is charged.

Section 4: Electric Circuits

Question Answer
What is a series circuit? A circuit in which parts are joined one after another such that the current in each part is the same.
What is a parallel circuit? A circuit in which the parts are joined in branches such that the potential difference across each part is the same.
What are the 3 parts of an electric circuit? an energy source, wires, and a load
What are the 2 types of electric circuits? series circuits and parallel circuits
The ______________ can be a battery, a photocell, a thermocouple, or an electric generator at a power plant. energy source
___________ connect the other parts of a circuit. They are made of conducting materials that have low resistance, such as copper. Wires
Examples of ___________ are light bulbs, appliances, televisions, and motors. Loads
What are two safety devices used in circuits? fuses and circuit breakers

Gilman Chpt 3 Vertebrates

Question Answer
Which is not a class of fish?
Names the groups of amphibians salamanders, caecilians, frogs and toads
Name characteristics of amphibians ectotherms, thin skin, live in water and land, breathe through lungs
What helps reptiles reduce water loss? thick skin
The vocal sac is or is not part of the amniotic egg? It is NOT
How do most reptiles breathe? lungs
How do most reptiles reproduce? internal fertilization
Are frogs and toads part of reptiles or amphibians? amphibians
Animals that can control their own body temperature are said to be what ? endotherms
Amphibians are often called what because they are sensitive to changes in the environment? ecological indicators
What big change made reptiles suited to live on land? amniotic egg
Reptiles, birds and animals have what that protects the embryo? amniotic eggs
Animals that live on land and on water are called what ? amphibians
When an immature animal form changes to an adult animal form it has gone through this? metomorphosis
What saclike organ allows amphbians to breathe? lungs
Immature frogs and toads that must live in water are called what? tadpoles
The line on boths sides of a fishes body are called what ? lateral line
When a organism depends on sources outside its body for heat they are called.. ectotherm
Animals that have a backbone are called? vertebrates
Animals that use chemical reactions in their body for heat are called? endotherms
a organ that exchanges oxygen from water with carbon dioxide from blood is called a gill
A gas filled sac used to control buoyancy? swim bladder
What are the most common reptiles? snakes and lizards
Name a fish that is a member of the largest class of fishes? goldfish
Which reptile has a narrow head and pointed snout (alligator or crocodile)? crocodile
Name a jawless fish lamprey
A cartilaginous fish does not have this? a bony skeleton
What animal looks like caecilians? earthworm
How do reptiles reproduce? internal fertizilation
Which group of reptiles have a shell? turtles and tortoises
This group has eyes and nostrils on top of their heads? crocs and gators
Name the most common reptile snakes and lizards
This reptile lives only in New Zealand tuataras

Our Natural Resources

Term Definition
Natural Resources those things which are provided by nature and are useful to us
Renewable resources which can be replinished after being used up
nonrenewable resources which cannot be replaced or renewed when once used up
decay the breakdown of dead plants and animals
loam a type of soil having a moderate amount of sand, silt, and clay
hydrologic (water)cycle the exchange of water among the surface of the earth, between plants and animals, and the atmosphere
mineral a naturally occurring substance mined from the earth
quarry a place where rock is dug from the ground, such as limestone
veneer a thin layer of high quality wood used to cover lesser quality wood
sawtimber trees that are cut and the wood used for a variety of products
pulpwood trees that are cut and ground up for use in the paper-making industry

Environmental Problems

Term Definition
EPA Environmental Protection Agency
pollution Contamination of a habitat with substances which make it less favorable for organisms
habitat loss When an organism loses a large part of its natural home
DDT Long-Lasting insecticide which caused the decline of some animal species (dichlor-diphenyl-trichlorethane)
ground water water standing in or moving through the soil and underlying rock layers (the source of water in wells and springs)
run-off the part of precipitation which flows over the land without sinking into the soil
erosion the washing away of soil particles by water, wind, ice, or earth movements such as landslides
topsoil the uppermost portion of the soil, which is richer in organic material and lighter in texture than the material below
silt fine mineral particles in the soil
clearcutting the cutting of all the trees in an area in one operation
sewage untreated waste material from homes and industry
siltation fine sand, or the like, carried by moving or running water and deposited as a sediment in our lakes and streams

Endangered Species

Term Definition
Carrying Capacity the number of organisms that can successfully live in an area
extinct a species of plant or animal which is no longer living on earth
endangered a species of plant or animal which is so low in number it may become extinct
threatened a species of plant or animal which is becoming scarce
habitat loss when an organism losses its home due to pollution
poaching the taking of animals illegally