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An ecosystem's living factors


An ecosystem's nonliving factors


The collection of biotic and abiotic factors of the area where an organism lives


The physical, chemical and biological factors a species needs in order to reproduce


A group of the same species living in one area


A group of different species living in one area


Encompasses all of the biotic and abiotic factors of a given area


A major regional or global community of organisms


Organisms that create their own food


Organisms that get their energy by eating living or once-living organisms


Organisms that only eat plants


Organisms that eat only animals


Organisms that eat both plants and animals


Detritivores that break down organic matter into simpler compounds, returning vital nutrients into the environment

Food Chain

A sequence that links species by their feeding relationship

Food Web

Shows the flow of energy within an ecosystem

Trophic levels

Levels of nourishment in a food chain

Energy Pyramid

A diagram that compares the energy used by producers, primary consumers, and other trophic levels


A close ecological relationship between two or more species


An interspecies interaction in which both organisms benefit from one another


A relationship between two organisms in which one receives an ecological benefit and the other is not harmed


A relationship between two animals in which one organism while the other is harmed

Carbon Cycle

Carbon moves into the biomass through photosynthesis and out through respiration and combustion


Pollutants move higher up the food chain as predators eat prey, accumulating in higher concentration in the bodies of predators

Thermal Pollution

Changes in water temperature affect the amount of oxygen it can supply

Natural Selection

Individuals with beneficial adaptations produce more offspring than those lacking them

Requirements for natural selection

Variation, heritability, differential mortality


A feature that allows an organism to better survive in its environment.

Survival of the fittest

Organisms who are better able to survive in their environment will generate more offspring relative to other members of the population

Directional Selection

Favors phenotypes at one extreme of a trait's range

Stabilizing Selection

Favors phenotypes at the intermediate point of a trait's range

Disruptive Selection

Favors phenotypes at both extremes of a trait's range

Divergent Evolution

Closely related species evolve in different directions

Convergent Evolution

Different species evolve toward similar characteristics

Homologous structures

Features similar in structure that appear in different organisms and have different functions

Analogous structures

Structures that perform similar functions-like flight- but are not similar in origin

Vestigial structures

Structures that had a function in an early ancestor


Animal that walks on two legs

Transitional fossils

A fossil near the branching point in which two species diverge in evolution

Law of Superposition

Youngest fossils rock on top, older fossils on the bottom.

Radioactive Dating

A technique that uses the natural decay rate of unstable isotopes to calculate the age of a material


The amount of time it takes for half the isotope in a sample to decay into a different element


Developing embryos show features indicating their evolutionary origins

Ionic bond

A bond formed by two oppositely charged ions

Covalent bond

A bond created when two or more atoms share a pair of electrons

Polar covalent bond

Covalent bonds that share electrons unequally

Non-polar covalent bond

Covalent bonds that share electrons equally

Hydrogen bond

An attraction between between a slightly positive hydrogen atom and a slightly negative atom (Oxygen or nitrogen)

Specific heat

The amount of heat required to increase a substance's temperature by one degree


Attraction among molecules of the same substance


Attraction between molecules of different substances

Good Solvent

Because the moH+lecules that form a hydrogen bond are predominantly positive and predominantly negative respectively, they can dissolve any polar and ionic bonds


Can bond with water


Cannot bond with water


Compound that increases the levels of H+ concentration in a solution. pH <7


Compound that removes H+ ions from a solution.
ph < 7


Macromolecules that can be broken down to create a usable source of energy for cells.


Simple sugar


Two simple sugars bonded together


Polymers of monosaccharides.


Made and stored by plants, can be used as a source of energy.


Made and stored by animals, can be used as a source of energy.


Major building block in plant cell structure


Non polar molecules utilized as a source of energy and in some occasions as part of a cell's structure


Store large amounts of energy in animals


Store large amounts of energy in plants

Saturated Fatty Acids

Contain fatty acids in which all carbon-carbon bonds are single bonds

Unsaturated Fatty Acids

Contain fatty acids with at least one carbon-carbon double bond


Polymers made of monomers called amino acids. Most varied carbon-based molecules in organisms

Amino acids

Building blocks of proteins, made up of carbon, hydrogen, nitrogen, and sometimes sulfur. 20 different variations are used in the construction of proteins


Catalysts for chemical reactions in living things

Active site

A region within the enzyme that binds to a protein or other molecule during a reaction

Nucleic acids

Polymers made up of monomers called nucleotides. Two main types are DNA and RNA

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