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a nonliving physical and chemical attribute of a system; e.g. light, temperature, wind patterns, rocks, soil, pH, pressure, etc. in an environment
the process that occurs in sex cells (sperm and egg) in which the number of chromosomes is reduced by half
involving quality or kind, recorded with a characteristic that cannot be expressed in numbers
a state in which metabolism slows in certain animals reducing their need for food and protecting them from cold
the edges where two or more tectonic plates meet; may be convertgent, divergent, or transform
periodic rise and fall of water level due to gravitational attraction of the sun and the moon acting on Earth
Ring of Fire
an area associated with plate boundaries around the Pacific Ocean that has a large amount of volcanic and earthquake activity
1. a straight line about which a body or a geometric figure may rotate 2. a straight line with respect to which a body or figure is symmetrical
all of the interactive feeding relationships by which energy and nutrients are transferred between organisms in a community
the change in the sunlit area of one celestical body (the moon) when viewe from another celestial body (Earth)
any organism such as a plant or protist that is able to make food through photosynthesis or chemosynthesis
measure of a star's light observed or received at a certain position (apparent magnitude)
the gradual increase of the temperature of Earth's lower atmosphere as a result of the increase in greenhouse gases
the solid, outer layer of the Earth that consists of the crust and the rigid upper part of the mantle
group of organisms of the same species living and reproducing in a particular geographic region
simple machine that is thick at one edge and tapered to a thin edge at the other for insertion in a narrow crevice
property that changes the chemical nature of matter when in the presence of other substances or conditions; e.g. heat of combustion, ractivity with water, pH, electromotive force
body organs responsible for getting food into and out of the body and for making use of food
the system by which oxygen gets taken into the body and an exchange of oxygen and carbon dioxide takes place
a celestial body made of hot gases in which nuclear fusion occurs and from which energy is radiated
a green structure of plant cells and other organisms in which food is made by photosynthesis
the factor measured or observed to obtain results (sometimes referred to as the responding variable), usually graphed on the y-axis
an intervening substance, such as air, through which a force acts or an effect is produced
1. describes compounds containing the element carbon 2. coming from an organism 3. food from an animal or plant that has been raised without synthetic pesticides, fertilizers, etc.
the process in which pollen is transferred from the male to the female part of ht flower or cone
survival of species
the theory that individuals in a population best able to obtain and use resources will survive and reproduce; i.e. survival of fittest
one of the measures of central tendancy (average); the sum of numbers in a set of data divided by the number of pieces of data
1. the energy released by a fission or fusion reaction 2. the binding energy of the atomic nucleus
a negatively charged subatomic particle that resides outside (but is bound to) the nucleus of an atom
all wateell as on Earth; in the atmosphere as well as in oceans, lakes, glaciers, rivers, streams, and underground reservoirs
a resource that forms at a rate that is much slower than the rate at which it is consumed; e.g. oil
an ecological unit composed of groups of organisms or a population of different species occupying a particular area
a form of electromagnetic energy that travels in waves through space and can be seen when it interacts with matter
1. the process by which individuals that are better adapted to their environment survive and reproduce more successfully than less well adapted individuals 2. a theory to explain the mechanism of evolution
substance with definite shape and volume, the atoms are packed tightly together in a regular pattern with little movement
conservation of mass
the principle by which matter is neither created nor destroyed when it undergoes a chemical reaction
the material between the nuclear and cell memberanes; icludes fluid, organelles, and various membranes
precipitation containing acids that forms in the atmosphere when industrial gas emissions (especially sulfur dioxide and nitrogen oxides) combine with water
this system consists of the heart and a closed system of vessels (arteries, veins, and capillaries) which provide a continuous flow of blood to your body, supplying the tissues with oxygen and nutrients
one of the known chemical substances that cannot be broken down further without changing its chemical properties
the genes that an organixm possesses for a particular trait-genotype is not just the expressed gene; instead, it includes any recessive genes masked by the dominant gene of a coded pair
chemical process in which a plant cell or protist uses energy from sunlight along with carbon dioxide and water to produce food (glucose) and oxygen
the gradual movement of continents by tectonic plates under Earth's surface which causes land masses to move toward or away from one another
the interacting system of a biological community and its non-living environmental surroundings
a sequence of organisms within a community, each of which uses the next, lower member of the sequence as an energy source
smallest particle of a substance that retains all the properties of the substance and is composed of one or more atoms
special quality or featrue of a substance or an organism that may be used for identification
a substance with an unstable atomic nucleus that loses energy by emitting particles or electromagnetic waves
classification of certain physical and chemical characteristics of an environment, such as tundra, grassland, etc.
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