WGU C190 Introduction to Biology Practice Test
Abiotic Non-living, may be within or made by a living organism.
Biotic Living. Matter is considered ______ if it was ever alive at some point in time
Atom Smallest level. The basic unit of matter. Consists of a dense nucleus surrounded
by electrons.
Molecule Second level. A chemical structure consisting of at least two atoms held together
by a chemical bond.
Macromolecule Third level. Biologically important molecules that are technically polymers.
Example: DNA.
Cell Fourth level. The fundamental unit of life. Essentially a tiny droplet of water and
other molecules enclosed by a fluid "skin" or membrane. The smallest and
simplest entity that possesses all the characteristics of life.
Organelle Fifth level. Compartments inside the cell that contain specific groups of
macromolecules and carry out specific cellular functions. One of these organelles
is the nucleus; it encloses the DNA within the cell.
Microorganism Sixth level. Single-celled life form. Consists of just one cell and include unicellular
organisms such as bacteria and protists.
Tissue Seventh level. Formed when similar cells work together to fulfill the same
detailed function.
Organ Eighth level. Collections of tissues that work together to carry out a common
general function. Present not only in higher level animals but also in plants.
Organ System Ninth level. Consists of functionally related organs. Mammals have many.
Organism Tenth Level. Individual living entities that survive and reproduce as a unit. For
example, each tree in a forest.
Population Eleventh level. Consists of all the individuals of a species living within a specific
area.
Community Twelfth level. Populations can interact with each other in positive and negative
ways, and together they form this.
Ecosystem Thirteenth level. Consists of all the living things in a particular area together with
the abiotic, or nonliving, parts of that environment.
Biosphere Fourteenth level. The highest level of organization in living systems. The
collection of all ecosystems on Earth. Includes all habitable zones on the planet,
including land, soil, and rocks to a great depth in the Earth's crust; water and ice;
and the atmosphere to a great height.
, WGU C190 Introduction to Biology Practice Test
Emergent Properties Characteristics of a system that are not present in any of its component parts.
Biology The scientific study of life and is the branch of science that studies living
organisms and the way organisms interact with their environments.
Homeostasis The ability or tendency of organisms and cells to maintain stable internal
conditions.
Nutrient Any matter an organism needs but cannot make for itself.
Energy The capacity to do work or to make a change in the location, temperature, or
structure of matter. Does not have mass and it does not take up space, but it can
be measured in terms of what it does.
Growth An increase in size.
Development Structure and function change in an orderly way as an organism passes through
its life cycle. An individual's pattern of _______ is partly determined by genetic
instructions.
Reproduction Occurs when an individual organism passes on its genetic information to a newly
independent organism, or offspring.
Evolution A scientific theory that explains how and why life changes over time. Provides the
explanation for why all living organisms share profound similarities, and yet, the
life forms on our planet are so incredibly diverse.
Natural Selection Individuals are always a bit different from their parents and from each other,
partly because of changes to their genes. These differences may be helpful or
harmful to the individuals that inherit them. In nature, individuals often have very
low odds of surviving to reproduce. Individuals with slightly harmful or even
average characteristics might be less likely to make it, and those with traits that
fit in very well with the local habitat will have the greatest chance to survive and
reproduce. This sorting process goes on generation after generation.
Atomic Mass The sum of the number of protons and the number of neutrons. The mass of an
atom.
Atomic Number The number of protons in an atom, displayed for each atom in the periodic table.
Chemical Bonds Attractions between atoms that hold atoms and molecules together.
Covalent Bonds Strongest chemical bond. Occurs between atoms of in the same molecule.
Electron pairs are shared, creating a strong bond between atoms.
electron Subatomic particle, located in shells on the outside of the nucleus, has a
negative charge and almost no mass.
, WGU C190 Introduction to Biology Practice Test
electronegativity A measure of the tendency of an atom to attract a bonding pair of electrons. How
strongly does an atoms attract bonding electrons to itself?
element Atoms with unique properties, designated by the atomic number.
hydrogen bond Weak chemical bond. Occurs between atoms in different molecules or parts of
molecules. Weak electrostatic attraction between areas of molecules with
opposite partial charges.
ion Positively or negatively charged atom.
ionic bond Moderately strong chemical bond. Occurs between atoms in the same molecule.
Electrons transfer from one atom to another.
isotope Any or two or more forms of a chemical element, having the same number of
protons in the nucleus, or the same atomic number, but having different numbers
of neutrons in the nucleus, or different atomic weights.
matter Anything that occupies space and has mass.
molecular formula A formula giving the number of atoms of each of the elements present in one
molecule of a specific compound.
neutron Subatomic particle, electrically neutral, located in the nucleus. Mass of one amu
nucleus Center of the atom. Contains equal number of protons and neutrons.
Periodic Table Chart organizing elements by atomic number and weight.
proton Subatomic particle, located in the nucleus, with a positive charge. Mass of one
amu.
valence electron Electrons on the outermost shell of the atom. Involved in chemical bonds.
Adhesion The attraction between water molecules and other molecules.
Cohesion Water molecules are attracted to each other, keeping the molecules together.
Hydrophilic Substances that will dissolve in water. Polar. They split into positive and negative
ions and dissolve in water. Examples: sugars and alcohols.
Abiotic Non-living, may be within or made by a living organism.
Biotic Living. Matter is considered ______ if it was ever alive at some point in time
Atom Smallest level. The basic unit of matter. Consists of a dense nucleus surrounded
by electrons.
Molecule Second level. A chemical structure consisting of at least two atoms held together
by a chemical bond.
Macromolecule Third level. Biologically important molecules that are technically polymers.
Example: DNA.
Cell Fourth level. The fundamental unit of life. Essentially a tiny droplet of water and
other molecules enclosed by a fluid "skin" or membrane. The smallest and
simplest entity that possesses all the characteristics of life.
Organelle Fifth level. Compartments inside the cell that contain specific groups of
macromolecules and carry out specific cellular functions. One of these organelles
is the nucleus; it encloses the DNA within the cell.
Microorganism Sixth level. Single-celled life form. Consists of just one cell and include unicellular
organisms such as bacteria and protists.
Tissue Seventh level. Formed when similar cells work together to fulfill the same
detailed function.
Organ Eighth level. Collections of tissues that work together to carry out a common
general function. Present not only in higher level animals but also in plants.
Organ System Ninth level. Consists of functionally related organs. Mammals have many.
Organism Tenth Level. Individual living entities that survive and reproduce as a unit. For
example, each tree in a forest.
Population Eleventh level. Consists of all the individuals of a species living within a specific
area.
Community Twelfth level. Populations can interact with each other in positive and negative
ways, and together they form this.
Ecosystem Thirteenth level. Consists of all the living things in a particular area together with
the abiotic, or nonliving, parts of that environment.
Biosphere Fourteenth level. The highest level of organization in living systems. The
collection of all ecosystems on Earth. Includes all habitable zones on the planet,
including land, soil, and rocks to a great depth in the Earth's crust; water and ice;
and the atmosphere to a great height.
, WGU C190 Introduction to Biology Practice Test
Emergent Properties Characteristics of a system that are not present in any of its component parts.
Biology The scientific study of life and is the branch of science that studies living
organisms and the way organisms interact with their environments.
Homeostasis The ability or tendency of organisms and cells to maintain stable internal
conditions.
Nutrient Any matter an organism needs but cannot make for itself.
Energy The capacity to do work or to make a change in the location, temperature, or
structure of matter. Does not have mass and it does not take up space, but it can
be measured in terms of what it does.
Growth An increase in size.
Development Structure and function change in an orderly way as an organism passes through
its life cycle. An individual's pattern of _______ is partly determined by genetic
instructions.
Reproduction Occurs when an individual organism passes on its genetic information to a newly
independent organism, or offspring.
Evolution A scientific theory that explains how and why life changes over time. Provides the
explanation for why all living organisms share profound similarities, and yet, the
life forms on our planet are so incredibly diverse.
Natural Selection Individuals are always a bit different from their parents and from each other,
partly because of changes to their genes. These differences may be helpful or
harmful to the individuals that inherit them. In nature, individuals often have very
low odds of surviving to reproduce. Individuals with slightly harmful or even
average characteristics might be less likely to make it, and those with traits that
fit in very well with the local habitat will have the greatest chance to survive and
reproduce. This sorting process goes on generation after generation.
Atomic Mass The sum of the number of protons and the number of neutrons. The mass of an
atom.
Atomic Number The number of protons in an atom, displayed for each atom in the periodic table.
Chemical Bonds Attractions between atoms that hold atoms and molecules together.
Covalent Bonds Strongest chemical bond. Occurs between atoms of in the same molecule.
Electron pairs are shared, creating a strong bond between atoms.
electron Subatomic particle, located in shells on the outside of the nucleus, has a
negative charge and almost no mass.
, WGU C190 Introduction to Biology Practice Test
electronegativity A measure of the tendency of an atom to attract a bonding pair of electrons. How
strongly does an atoms attract bonding electrons to itself?
element Atoms with unique properties, designated by the atomic number.
hydrogen bond Weak chemical bond. Occurs between atoms in different molecules or parts of
molecules. Weak electrostatic attraction between areas of molecules with
opposite partial charges.
ion Positively or negatively charged atom.
ionic bond Moderately strong chemical bond. Occurs between atoms in the same molecule.
Electrons transfer from one atom to another.
isotope Any or two or more forms of a chemical element, having the same number of
protons in the nucleus, or the same atomic number, but having different numbers
of neutrons in the nucleus, or different atomic weights.
matter Anything that occupies space and has mass.
molecular formula A formula giving the number of atoms of each of the elements present in one
molecule of a specific compound.
neutron Subatomic particle, electrically neutral, located in the nucleus. Mass of one amu
nucleus Center of the atom. Contains equal number of protons and neutrons.
Periodic Table Chart organizing elements by atomic number and weight.
proton Subatomic particle, located in the nucleus, with a positive charge. Mass of one
amu.
valence electron Electrons on the outermost shell of the atom. Involved in chemical bonds.
Adhesion The attraction between water molecules and other molecules.
Cohesion Water molecules are attracted to each other, keeping the molecules together.
Hydrophilic Substances that will dissolve in water. Polar. They split into positive and negative
ions and dissolve in water. Examples: sugars and alcohols.
