 | Term | Definition |
| |
atom |
basic unit of matter |
| |
nucleus |
center of the atom containing protons and neutrons |
| |
electron |
negatively charged particle circulating around the nucleus |
| |
proton |
positively charged particle of an atom |
| |
neutron |
neutral particle of an atom |
| |
element |
pure substance consisting entirely of one type of atom |
| |
isotope |
atoms of the same element but with a different number of neutrons |
| |
compound |
substance formed by the chemical comination of two or more compounds in definite proportion |
| |
ionic bond |
Formed when one or more electrons are transferred from one atom to another |
| |
ion |
positively or negatively charged atom |
| |
covalent bond |
forms when electrons are shared between atoms |
| |
molecule |
smallest unit of a compound |
| |
van der waals force |
force of attraction between large molecules |
| |
cohesion |
an attraction between molecules of the same substance |
| |
adhesion |
an attraction between molecules of different substances |
| |
mixture |
two or more elements or compounds that are physically mixed but not chemically combined |
| |
solution |
mixture where all components are even distributed |
| |
solute |
the substance that is dissolved |
| |
solvent |
the substance in which the solute is dissolved |
| |
suspension |
mixtures of water and nondissolved materials |
| |
pH scale |
measures the concentration of hydrogen ions in a solution |
| |
acid |
solution with a higher concentration of hydrogen ions than water |
| |
base |
solution witha lower concentration of hydrogen ions than water |
| |
buffer |
a weak acid or weak base that prevents sudden changes in pH |
| |
light microscope |
produce magnified images by focusing visible rays of light |
| |
metric system |
system of measurement based on the number 10 used by scientists |
| |
evolve |
change in a group of organisms over time |
| |
homeostasis |
the process by which organsims keep their internal conditions reltively stable |
| |
metabolism |
combination of chemical reactions through which an organism builds up or breaks down materials as it carries out its life processes |
| |
asexual reproduction |
new organism formed from a single parent |
| |
sexual reproduction |
two cells from different parents unite to form the first cell of a new offspring |
| |
cell |
a collection of living matter enclosed in a barrier that seperates it from its surroundings |
| |
biology |
branch of science that seeks to understand the living world |
| |
Theory |
a well tested explanation that unifies a broad range of observations |
| |
responding variable |
the changs that occur in response to the manipulated variable |
| |
manipulated variable |
part of an experiment that is deliberately chnaged |
| |
controlled experiment |
used to test a hypothesis by changing only one variable at a time |
| |
spontaneous generation |
incorrect theory stating that living things could arise from nonliving matter |
| |
hypothesis |
possible explanation for a set of observations or an answer to a scientific question |
| |
inference |
logical interpretation based on prior knowledge and experience |
| |
Observation |
using one of the 5 senses |
| |
data |
information gathered from observations |
| |
science |
An organized way of using evidence to learn about the natural world |
| |
monomer |
small units of larger molecules |
| |
polymer |
large molecule formed by the joining of multiple monomers |
| |
carbohydrate |
main source of energy for all living things |
| |
monosaccharide |
single sugar monomers |
| |
polysaccharide |
large sugar polymers |
| |
lipid |
macromolecules used for energy storage, cell membranes, and waterproofing |
| |
nucleic acid |
macromolecules that store and transmit hereditary, or genetic, information |
| |
nucleotide |
monomer for nucleic acids |
| |
protein |
macromolecule that provides structure and regular processes for the cells |
| |
amino acid |
monomer for proteins |
| |
macromolecule |
large molecule formed by the joining together of smaller molecules |
| |
chemical reaction |
a process that changes one set of chemicals into another set of chemicals |
| |
reactant |
the elements or compounds that enter into a chemical reaction |
| |
product |
the elements or compounds that are produced by a chemical reaction |
| |
activation energy |
The energy needed to start a chemical reaction |
| |
catalyst |
A substance that speeds the rate of a chemical reaction by lowering the amount of activation energy required |
| |
enzyme |
proteins that act as a cell's biological catalysts |
| |
substrate |
The reactants of an enzyme catalyzed reaction |
Share on Facebook
Share on MySpace