chapters 1-2 Flashcards
define deductive reasoning
when general observations and premises lead to specific results and predictions
describe electrons and their charge
electrons are subatomic particles that determine the chemical reactions and have a negative charge
order of the first three steps of the scientific method
observe, hypothesis, and experiment
order of the last three steps of the scientific method
analysis, conclusion, and communicate results
define ionic bond
the attraction between two oppositely charged ions
which bond is easily broken
hydrogen bond
define polar covalent bonds
bonds with unequal sharing of electrons
water is a ____ molecule
polar
define biology
the scientific study of life, also known as a multidisciplinary science drawing on insights from other sciences
what are the five unifying themes in biology
organization, information, energy and matter, interactions, and evolution
what is the ecological organization from smallest to largest
molecules, organelles, cells, tissues, organs, organisms, populations, communities, ecosystems, and biosphere
define biosphere
life on earth, atmosphere
define ecosystem
all living things in a particular area
define communities
group of organisms in a specific ecosystem
define population
individuals of a species living in a specific area
define organisms
individual living things composed of matter
define organs
body part made of tissues with specific function
define tissues
group of cells that work together
define cells
life’s fundamental unit of structure and function, all cells are membrane bound
define organelles
functional components of a cell
define molecules
chemical structure
what is the cell theory
all living organisms are made from cells
define eukarya cells
includes all eukaryotic organisms; including plants, fungi, animals, protists
define prokaryote cells
known as cells of bacteria and archaea
define inquiry
the search for information and explanations of natural phenomena
define inductive reasoning
repeating specific observations can lead to important generalizations, draws conclusions through logical process of induction
define controlled experiment
compares an experimental group with a control group, the control groups are used to cancel the effects of unwanted variables, this does not mean that all unwanted variables are kept constant
dependent variable versus the independent variable
the independent variable (x-axis) is the cause, and the dependent variable (y-axis) is the effect; the independent variable is being controlled and the dependent variable is the one that changes because of the control
define theory
broader scope than a hypothesis, general and can lead to new testable hypotheses, supported by a large body of evidence in comparison to a hypotheses
define matter
matter takes up space and has mass, made up of elements
define element
substance that cannot be broken down to other substances by chemical reactions
define compound
a substance consisting of two or more elements in a fixed ratio
what determines an atom’s identity
the number of protons
what does an atom’s electron distribution determine
its ability to form bonds
what are the four main elements that make up 96% of all living matter
hydrogen, carbon, nitrogen, and oxygen
what are the three subatomic particles and their charges
neutrons (neutral charge n0) protons (positive charge p+) electrons (negative charge e-)
how do you find an elements atomic number
the number of protons
how do you find an elements mass number
the sum of protons plus neutrons in the nucleus
how do you find an elements atomic mass
approximated by the mass number
define valence electrons
the electrons located at the outermost shell of an atom, elements with a full valence shell are chemically inert
define isotopes
two atoms of an element that differ in the number of neutrons
define radioactive isotopes
isotopes that decay spontaneously, giving off particles and energy
define covalent bonds
the sharing of a pair of valence electrons by two atoms, nonpolar is equal sharing and polar is unequal sharing
define electronegativity
an atoms attraction for the electrons in a covalent bond
strongest bonds in organisms
covalent bonds
weak bonds in organisms include
ionic and hydrogen bonds
define hydrogen bond
when a hydrogen atom covalently bonded to one electronegative atom is also attracted to another electronegative atom
explain van der waals interactions
attractions between molecules that are close together as a result of these charges, interactions can be strong
define reactants and products
reactants are starting molecules and products are final molecules
what are the three domains of life
bacteria, archaea, and eukaryotes
two important qualities of a scientific hypothesis
must be testable and falsifiable
biological science cannot be done without
DNA
the attraction between two oppositely charged ions is called a/an
ionic bond
polar covalent bonds are characterized by
unequal sharing of electrons
how does a molecule differ from a compound
a molecule is a group of two or more atoms bonded together and a compound is a substance
formed by two or more different types of elements, all compounds are molecules
but not all molecules are compounds.
