Correct Answers
theory Correct answer-a general set of principles (supported by evidence) that explains some
aspect of nature; never PROVEN true
scientific method Correct answer-a systematic process through which scientists formulate
hypotheses and make conclusions about the natural world
observation--> question--> hypothesis-->
experiment--> conlcusion
hypothesis Correct answer-a tentative, testable explanation that is tested via observation or an
experiment; must be falsifiable
falsifiable Correct answer-able to be proven false; testable
> ex. a hypothesis that is not shown to occur in an experiment is falsified
biology Correct answer-the study of life and living things
characteristics of life Correct answer-all living things must...
1. use energy
2. respond to environment
3. maintain a stable internal environment (homeostasis)
4. reproduce
5. possess inherited genetic information (DNA)
6. be made of 1 or more cells
7. be evolved from other living things
8. be highly organized (compared to nonliving objects)
high organization (hierarchy) Correct answer-life is highly organized into a categorical hierarchy
> ex. atom--> molecule--> organelle--> cell--> tissue-->
organ--> organ system--> organism--> population-->
community--> ecosystem--> biosphere
reproduction Correct answer-an organism's ability to pass on its genetic information to offspring;
i.e. "making more of yourself"
cell Correct answer-the smallest unit of life
cell theory Correct answer-1. cells are the basic unit of life
2. all living things are made up of cells
3. cells can only come from preexisting cells
DNA Correct answer-deoxyribonucleic acid; a complex molecule used to transmit genetic
information from one generation to the next
homeostasis Correct answer-the tendency of living things to maintain a relatively stable internal
environment
> ex. shivering when cold to warm yourself back up, throwing up after eating bad food to make sure
you're not poisoned/injured
, evolution Correct answer-Charles Darwin's idea that a species adaptively changes over time; a
central theme of biology
provisional assent Correct answer-every scientific assertion (whether it's a hypothesis or theory) is
subject to revision/change in the future
spontaneous generation Correct answer-the belief that life can arise from nonliving material
> ex. maggots are "born" from rotting meat
Louis Pasteur Correct answer-French scientist who used a series of experiments to prove the idea
of spontaneous generation is false; i.e. life cannot magically arise from non life
atom Correct answer-fundamental building blocks of matter; made up of protons, neutrons, and
electrons
proton Correct answer-subatomic particle with a positive (+) charge, located in the nucleus, mass =
1 amu
neutron Correct answer-subatomic particle with no charge, located in the nucleus, mass = 1 amu
valence electrons Correct answer-the number of electrons located in an atom's outermost
(valence) electron shell; determines that atom's chemical properties/bonding patterns
element Correct answer-a substance made of only one type of atom, defined by its atomic number
(number of protons); CANNOT be further broken down into simpler parts
electron Correct answer-subatomic particle with a negative (-) charge, located in outer shell within
orbitals, no real mass
octet rule Correct answer-all atoms attempt to fill their valence electron shell fully
(2 electrons in first shell, 8 electrons in all other shells)
isotope Correct answer-atoms of the same element that differ in their number of neutrons (thus,
no charge difference)
> ex. C12, C13, C14 (isotopes of carbon)
hydrogen Correct answer-the simplest element, contains 1 proton, 1 electron, and no neutrons
deuterium Correct answer-an isotope of hydrogen (H) with 1 neutron added
tritium Correct answer-an isotope of hydrogen (H) with 2 neutrons added
chemical bonding Correct answer-the process of atoms linking to one another...
1. ionic bonds
2. covalent bonds
3. hydrogen bonds
ion Correct answer-a charged atom that is the result of a gain or loss of electrons; proton/neutron
numbers stay the same between an ion and its neutral (uncharged) form
> ex. gain of electron--> more negative charge, like Cl-