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Praxis 2 science

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Layers of the Earth
crust, mantle, core
Rocks that make up the Earth
Igneous Rocks, Sedimentary Rocks, Metamorphic Rocks
Igneous Rocks
formed from cooling of molten rock, called lava.
Metamorphic Rocks
formed from older rocks under intense heat or pressure at depths beneath the earth's surface
Sedimentary Rocks
formed in layers contain plant and animal remains,
hydrosphere
oceans
Saltwater bodies
oceans and seas containing saltwater and saltwater ecosystems.
minerals found in saltwater
salt (sodium chloride), iron, phosphates, nitrates, magnesium
Freshwater bodies
lakes, streams, rivers, ponds, marshes.
shore
shoreline, Beaches, Sandbar, Spit, Bay, Lagoon, Barrier islands, Arches and stacks
shoreline
the boundary where the land meets the sea
Beaches
deposits of sand and other fragments of rock left along the shoreline boundary
Sandbar
water currents deposit sand and debris in deeper water, parallel to the shore, and build up
Spit
a narrow piece of land which forms along a curved shoreline
Bay
part of the coastline where the rock has been gradually eroded by a large body of water
Lagoon
a body of water cut off from the sea by a sandbar or reef.
Barrier islands
islands made from sand and debris deposited parallel to the shore
Arches and stacks
formations of resistant rock left standing after softer rock had been worn away (eroded) by
Continental shelf
underwater land at the edges of the continents
Continental slope
a steep slope running from the edge of the continental shelf down to the ocean floor
Abyssal plain
wide, flat area that makes up most of the ocean floor
Mid-oceanic ridges
mountain ranges on the ocean floor
Weathering
the breakdown of rock to form sediment.
Erosion
weathered particles are moved from one location to another.
five major oceans
Pacific, Atlantic, Indian, Artic and Antarctic
3 major types of clouds
Stratus, Cumulus, Cirrus
Stratus
smooth layers of low clouds
Cumulus
turret-shaped tops, flat bottoms
Cirrus
feather-like clouds made of ice crystals
Climate
long-range weather patterns
Weather
short-term conditions of the atmosphere
6 major biomes on land:
rainforest, desert, grassland,deciduous forest, boreal forest, tundra
"Big Bang" Theory
named in 1950 by British scientist, Fred Hoyle
Paleontology
the science studying former life through fossils
Geologic time scale
sequence of events in the Earth's history
Paleozoic Era
543 -248 million years ago
Mesozoic era
248 - 65 million years ago
Cenozoic era
65 million years ago to present
Galaxy
a system of stars, gases, and dust all held together as a group by gravity
Milky Way
Earth's galaxy
Solar system
consists of a star, a group of planets and their satellites
9 planets
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto
Comets
large clumps of ice, dust and frozen gases that travel around the Sun in long elliptical orbits
Meteoroids
very small asteroids which orbit the Sun.
Meteors
"shooting stars" or "falling stars".
Cells
basic unit of structure
Nucleus
the "brain" of the cell; houses the codes that control cell activities; often centrally located
ER - (Endoplasmic Reticulum)
tubes where cell substances are made
Chromosomes
rod-shaped bodies contained within the nucleus which carry the genetic code for reproduction
Cell Membrane
controls the movement of materials in and out of the cell; outer "wall."
Nuclear membrane
controls the movement of materials in and out of the nucleus; inner "wall."
Golgi bodies
assemble, release, and store chemicals
Ribosomes
make proteins
Cytoplasm
substance which holds all other parts in suspension within the cell
Mitochondria
the "powerhouse" of the cell; the site of energy production and release
Lyosomes
eat up waste materials
Vacuoles
store water
Cell wall
gives shape and support to plant cells
Chloroplasts
contain chlorophyll which traps sunlight to help make food via photosynthesis
Taxonomy
the science of classifying living things
Phototropism
growth of a plant's stem towards the sunlight
Geotropism
is the growth of roots downwards, towards gravity
Roots
anchor plants in the ground and bring in minerals and water from the soil
Stems
hold up the rest of the plant, and have tubes that carry water and food between the leaves and the roots
Leaves
part of the plant where most of the food is made
Diffusion
movement of atoms or molecules in a solution or gas
Transpiration
the evaporation of water from plants
Respiration
plants use oxygen to break down sugar to release energy
Organ Systems
group of organs that work together to carry out a particular function
Ligaments
connective tissues that bind bones or cartilage together.
Tendons
are connective tissue that binds muscles to bones
Cartilage
a tough, elastic tissue that can withstand pressure
Muscles
cells and tissues that allow movement of an organ or body part
Skeletal muscle
attached to bones and allows voluntary (controlled by conscious thought) movement of limbs
Smooth muscle
found in internal organs and aids in involuntary (controlled by autonomic nervous system) movement in respiratory, excretory and reproductive systems
Cardiac muscle
forms powerful walls of the heart; controlled by autonomic nervous system
Cornea
transparent thin outer covering of the eye that protects the iris and pupil
Pupil
small hole in the center of the eye, through which light enters
Iris
the colored muscles in the eye
Lens
bends the rays of light to focus them on the retina
Retina
lines the back wall of the eye and contains rods and cones, which are light-sensitive receptor cells
Optic nerve
carries the impulses to the brain, where they are interpreted.
Heart
strong muscle which pumps blood to the lungs, organs, tissues and cells
Aorta
is the main artery leaving the heart
Carotid artery
supplies blood to the brain
Superior vena cava
the largest vein emptying into the heart
Capillaries
smallest vessels in the body where oxygen and carbon dioxide are exchanged
Digestion
breaking down of food
Reproduction
how organisms make new organisms
Asexual reproduction
only one parent is needed to reproduce
Budding
reproduce by growing a new organism out of a bud off a parent
Fragmentation
animal divides itself and each piece grows the missing parts and becomes a full offspring
Parthenogenesis
production of offspring from eggs which do not require fertilization by a "partner."
Trait
characteristic, such as eye color or height, which is coded for by genes contained on chromosomes
Heredity
passing on of traits from parents to offspring
Dominant traits
traits people can see that you have; a dominant gene overpowers a recessive gene
Recessive traits
traits you may have, but people cannot see because they are not expressed
Genes
the coded instructions in DNA; the "genetic code;" they are the basic units of inheritance
Chromosomes
thread-like structures in the nucleus of every cell that carry genetic codes for the cell's activity
Mitosis
2-step process by which all body cells of multi-cellular organisms multiply
Anemia
lack of red blood cells in the blood
Hemophilia
lack of platelets, which help the blood to clot
Goiter
lack of iodine and the over-activity of the thyroid gland
Rickets
lack of vitamin D.
Down's Syndrome
genetic error in which an extra chromosome (#21) is passed on
Human Life cycle
infancy, childhood, adolescence and adulthood.
Homeostasis
tendency of a living organism towards balance and equilibrium
Endocrine system
glands which secrete hormones directly into the blood stream
Pituitary gland
small gland attached to the base of the brain which secretes hormones that influence growth, metabolism, and reproduction
Pancreas
gland behind the stomach that functions in both the endocrine and digestive system
Thyroid gland
large gland in the front of the neck, it secretes hormones which regulate growth and metabolism
Migration
the movement by animals over long distances in order to reproduce, mate, raise young, or find food
Hibernation
a long period of rest or inactivity by an animal, usually in the winter, to conserve energy
Reflex behavior
automatic response to a stimulus
Instinctive behavior
inborn responses to stimuli
Unity
state or quality of being in accord; harmony
Adaptation
series of changes or characteristics that are made by an animal which enable it to survive in its environment
Evolution
1. chemical evolution -organic molecules were first formed. 2. development of single-celled organisms- capable of asexual reproduction. 3. development of complex, multi-cellular organisms - capable of sexual reproduction.
Theory of "Natural Selection."
theory that the earth's species have changed and diversified over time. first described by Charles Darwin. expression "survival of the fittest" was used to describe this process in the 19 century
Population
number of individuals of one species in a community.
Community
populations of plants and animals living together in a particular habitat
Ecosystems
describes a community, its habitat, and all of the relationships within that habitat.
Ecology
the study of the relationships between organisms and their habitat
Food chain
one organism in an ecosystem consumes another organism
Green plants
producers because they make their own food
Herbivores
animals that eat green plants, are primary consumers
Carnivores
animals that eat meat
Decomposers
break down wastes and dead organisms and return the raw materials to the ecosystem
Birth
main way new individuals join a population
Death
main way individuals leave a population
Immigration
individuals move into a population from elsewhere, thus increasing its size
Emigration
individuals move out of a population to elsewhere, thus decreasing its size
Matter
anything that has mass and takes up space
Solids
have a definite size and shape; particles are packed together tightly and are in a regular pattern
Liquids
have a definite size and volume, but no definite shape; particles are more active and farther apart than a solid
Gases
no definite size or shape; a gas will fill whatever space it occupies; particles move freely and are even farther apart from each other than a liquid
Mass
the amount of matter in an object; its "size"; all matter has mass and takes up space
Weight
the force of the Earth's gravity which pulls down on an object
Density
amount of mass packed into a given unit of volume; density is the relative "heaviness" of an object
Viscosity
the property of a liquid which describes how easily it pours
Freezing point
the temperature at which a liquid will become a solid.
Boiling point
temperature at which a liquid will become a gas
other physical properties of matter
Color, Hardness, Size, Shape and Odor
Sublimation
a change from a solid to a gas without going through a liquid state
Condensation
a change from a gaseous to a liquid state caused by lowering the temperature
Evaporation
a change from a liquid to a gaseous state caused when a liquid is heated to its boiling point
pH scale
a range of numbers that measure of the strength of an acid or base
Catalyst
a substance which hastens a chemical reaction without itself undergoing chemical change
Mixture
contains 2 or more different substances that have not undergone a chemical reaction
Solution
a mixture in which small particles are spread evenly throughout a liquid, resulting in a physical change, but not a chemical change, in the liquid
Atoms
the smallest piece of matter that can exist on its own
Element
substance which contains only one kind of atom An element cannot be broken down by physical or chemical means. There are 103 elements that are named with most of them occurring naturally
Periodic Table
lists the elements in order of their atomic number displays the full name of each element, its symbol, as well as its atomic mass
Molecule
a combination of 2 or more atoms held together by a force between them
Compound
substances made up of two or more elements that are combined in a chemical reaction
Motion
a change in position of an object or substance
Force
a push or pull acting on an object. A force can start a motion, stop a motion
Speed
the rate of motion of a body; expressed in distance per unit of time
Velocity
speed in a particular direction
Distance
the extent of space between two objects or places
Acceleration
the rate of change in velocity when the velocity increases
Deceleration
the rate of change in velocity when the velocity decreases
Centripetal force
pulls the object inward
Centrifugal force
pushes an object outward
Newton's law of motion 1
Every object at rest remains at rest, and every object in motion continues moving in a straight line at a steady rate, unless acted upon by an outside force
Inertia
tendency of an object to resist any change in velocity
Newton's law of motion 2
amount of force needed to change the speed of an object depends on the mass of the object and the amount of acceleration, or deceleration, needed
Newton's law of motion 3
To every action there is an equal and opposite reaction
Friction
the resistance of an object to the medium through which, or upon which, it is traveling
Equilibrium
condition in which all forces and influences acting upon an object cancel each other out and equalize
Potential energy
depends on the position of an object
Kinetic Energy
depends on the motion of an object
Radiant energy
energy that travels through space in the form of waves
Chemical energy
energy released during a chemical reaction
Solar energy
energy that is trapped from the Sun
Nuclear energy
energy stored in the nucleus of every atom may be released by a fission reaction or by a fusion reaction
fission
splitting the atoms
fusion
joining the nuclei of atoms
Lever
a bar that pivots about a fixed point and thus reduces the amount of the force required to lift an object
Pulley
one or more wheels connected by a loop of rope which reduces the amount of force
Inclined plane
slanted surface used to raise objects
Wheel and Axle
large wheel attached to a smaller rod; the wheel rotates about the axle
Screw
reduces the amount of force needed to do the work
Wedge
reduces the amount of force needed to do the work
Waves
rhythmic disturbances that carry energy
Water waves
are oscillating (up and down) movements in which the surface of water rises and falls
Sound waves
the action of two objects hitting each other causes the molecules of air to vibrate
Electromagnetic (EM) spectrum
the arrangement of different types of waves, according to their wavelengths
Electromagnetic waves
are transverse waves that travel at the speed of light in a vacuum
Light waves
have medium-sized wavelengths, consist of tiny particles of radiation travel fast and straight, they don't require a material to travel through, and they can move through a vacuum.
Infrared waves
the next longest wavelengths after light waves
Microwaves
the next longest wavelengths after infrared rays
Radio waves
have the longest wavelengths and have lowest frequencies
X-rays and gamma rays
have some of the shortest waves in the spectrum
Conduction
the transfer of heat from particle to particle that occurs when two substances of different temperatures come into contact with each other
Convection
the transfer of heat by the movement of matter
Radiation
the transfer of heat that does not require matter
Conductors
substances that conduct heat or electricity
Insulators
substances that slow the movement of heat or electricity
Electricity
the flow of electrons (negatively charged atomic particles) through a conductor to create energy
Volts
measures the push of electricity through a conductor
Amperes (Amps)
measure the flow of electrical current (the steady flow of electrons through a conductor)
Ohms
are a unit of measurement of electrical resistance. Resistance is the opposition of the flow of something
Magnetism
the property of some objects, like iron, aluminum, nickel and cobalt, which allows them to attract other magnetic objects to themselves like poles repel; opposite poles attract
Electrical circuit
an unbroken path formed by electrical conductors through which electricity can flow
Echoes
sound waves can bounce off (reflect) objects which have smooth surfaces
Scientific inquiry
conducting investigations and looking for explanations to questions about the physical world
Nicolaus Copernicus
demonstrated that the Sun is the center of the solar system
Galileo Galilei
wrote about acceleration, motion and gravity; developed the first astronomical telescope and made many discoveries in astronomy