nucleus
double membraned sac that encloses a cell's DNA
bacterium
member of single-celled organisms
eukaryote
organism whose cells characteristically have a nucleus
protist
member of a diverse group of simple eukaryotes
homeostasis
Set of processes by which an organism keeps its internal conditions within tolerable ranges
growth
in multicelled species, an increase in the number, size, and volume of cells
development
multistep process by which the first cell of a new multicelled organism gives rise to an adult
reproduction
Process by which parents produce offspring
inheritance
transmission of DNA to offspring
energy
capacity to do work
nutrient
substance that an organism needs for growth and survival but cannot make for itself
producer
Organism that makes its own food using energy and nonbiological raw materials from the environment
photosynthesis
Process by which producers use light energy to make sugars from carbon dioxide and water
consumer
organism that gets energy and nutrients by feeding on tissues, wastes, or remains of other organisms
atom
fundamental building block of all matter
molecule
An association of two or more atoms
cell
smallest unit of life
organism
Individual that consists of one or more cells
tissue
in multicellular organisims, a group of similar cells that carry out a common function
organ
in multicelled organisms, a grouping of tissues engaged in a collective task
organ system
in multicelled organisms, set of interacting organs that carry out a particular body function
population
group of individuals of the same species that live in the same area
community
all populations of all species in a given area
ecosystem
A community interacting with its environment
biosphere
All regions of Earth where organisms live
fungus
type of eukaryotic consumer that obtains nutrients by digestion and absorption outside the body
plant
multicelled, typically photosynthetic producer
animal
multicelled consumer that develops through a series of stages and moves about during part or all of its life cycle
archean
member of a group of single-celled organisms that differ from bacteria
species
Type of organism
taxonomy
the science of naming and classifying organisms
genus
a group of species that share a unique set of traits
specific epithet
Second part of scientific name.
taxon
Linnaean category; a grouping of organisms
experimental group
in an experiment, the group exposed to the treatment
control group
in an experiment, the group of participants that doesn't receive the manipulation
Scientific Method
Making, testing, and evaluating hypotheses
atom
particle that is a fundamental building block of all matter
proton
positively charged particle that occurs in the nucleus of an atom
neutron
uncharged subatomic particle in the atomic nucleus
electron
Negatively charged subatomic particle
charge
electrical property. opposite charges attract, and like charges repel
nucleus
core of an atom; occupied by protons and neutrons
atomic number
number of protons in the nucleus of an atom
element
A pure substance that cannot be broken down into other substances by chemical or physical means
periodic table
tabular arrangement of all known elements by their atomic number
isotopes
Forms of an element that differ in the number of neutrons their atoms carry
mass number
total number of protons and neutrons
radioisotope
Isotope with an unstable nucleus
radioactive decay
process by which an unstable element naturally changes into another stable element
tracer
a molecule labelled with a detectable substance
shell model
model of electron distribution in an atom
ion
charged atom
electronegativity
Measure of the ability of an atom to pull electrons away from other atoms
chemical bond
an attractive force that arises between two atoms when their electrons interact
molecule
group of atoms bonded together
compound
Group of molecules
mixture
an intermingling of two or more types of molecules
ionic bond
type of chemical bond in which a strong mutual attraction links ions of opposite charge
covalent bond
chemical bond in which two atoms share a pair of electrons
polarity
Any separation of charge into distinct positive and negative regions.
hydrogen bond
Attraction between a slightly positive hydrogen atom and a slightly negative atom.
solvent
Liquid substance that will dissolve another substance
solute
A dissolved substance
salt
compound that releases ions other than H+ and OH- when it dissolves in water
hydrophilic
Describes a substance that dissolves easily in water
hydrophobic
Describes a substance that resists dissolving in water
cohesion
Tendency of molecules of the same kind to stick to one another
evaporation
Transition of a liquid to a vapor
temperature
Measure of molecular motion
concentration
The number of molecules or ions per unit volume of a solution
pH
measure of the number of hydrogen ions in a fluid
acid
substance that releases hydrogen ions in water
base
substance that accepts hydrogen ions in water
buffer
A solution that minimizes changes in pH when extraneous acids or bases are added to the solution.
hydrocarbon
Compound or region of one that consists only of carbon and hydrogen atoms
functional group
a group of atoms bonded to a carbon of an organic compound
monomers
Molecules that are subunits of polymers
polymer
molecule that consists of multiple monomers
metabolism
All enzyme-mediated chemical reactions by which cells acquire and use energy
enzyme
compound (usually a protein) that speeds up a reaction without being changed by it
condensation
process by which enzymes build large molecules from smaller subunits; water also forms
hydrolysis
process by which an enzyme breaks a molecule into smaller subunits by attaching a hydroxyl group to one part and hydrogen atoms to the other
carbohydrate
molecule composed of carbon, hydrogen, and oxygen in 1:2:1 ratio
Studied by 6 People