Campbell Biology, Exam I

biology

the scientific study of life

emergent properties

new properties that arise with each step upward in the hierarchy of life, owing to the arrangement and interactions of parts as complexity increases

systems biology

an approach to studying biology that aims to model the dynamic behavior of whole biological systems based on a study of interactions among the system’s parts

eukaryotic cell

a type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles

prokaryotic cell

a type fo cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles

genes

a discrete unit of hereitary information consisting of a specific nucleotide sequence in DNA

gene expression

the process by which information encoded in DNA directs the synthesis of proteins or, in some cases, RNAs that are not translated into proteins and instead functions as RNAs

genome

the genetic material of an organism or virus; the complete complement of an organism’s or virus’s genes along with its noncoding nucleic acid sequences

genomics

the systematic study of whole sets of genes and their interactions within a species, as well as genome comparisons between species

proteomics

the systematic study of sets of proteins and their properties, including their abundance, chemical modifications, and interactions

proteome

the entire set of proteins expressed by a given cell, tissue, or organism

bioinformatics

the use of computers, software, and mathematical models to process and integrate biological information from large data sets

consumer

an organism that feeds on producers, other consumers, or nonliving organic material

producers

an organism that process organic compounds from carbon dioxide by harnessing light energy (in photosynthesis) or by oxidizing inorganic chemicals

feedback regulation

the regulation of a process by its output or end product

vessel

a continuous water-conducting micropipe found in most angiosperms and a few nonflowering vascular plants

climate change

a directional change in temperature, precipitation, or other aspect of the global climate that lasts for three decades or more

evolution

descent with modification; the process by which species accumulate differences from their ancestors as they adapt to different environments over time

bacteria

one or two prokaryotic domains, the other being archaea

archaea

one of two prokaryotic domains, the other being bacteria

eukarya

the domain that includes all eukaryotic organisms

natural selection

a process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits

science

an approach to understanding the natural world

inquiry

the search for information and explanation, often focusing on specific questions

data

recorded observations

inductive reasoning

a type of logic in which generalizations are based on a large number of specific observations

hypothesis

a testable explanation for a set of observations based on the available data and guided by inductive reasoning; is a narrower in scope than a theory

experiment

a scientific test; often carried out under controlled conditions that involve manipulating one factor in a system in order to see the effects of changing that factor

deductive reasoning

a type of logic in which specific results are predicted from a general premise

controlled experiment

an experiment designed to compare an experimental group with a control group; ideally, the two groups differ only in the factor being tested

varibles

a factor that varies in an experiment

theory

an explanation that is broader in scope than a hypothesis, generates new hypotheses, and is supported by a large body of evidence

model organism

a particular species chose for research into broad biological principles because it is representative of a larger group and usually easy to grow in a lab

matter

anything that takes up space and has mass

element

any substance that cannot be broken down to any other substance by chemical reactions

compound

a substance consisting of two or more different elements combined in a fixed ratio

essential elements

a chemical element required for an organism to survive, grow, and reproduce

trace elements

an element indispensable for life but required in extremely minute amounts

atom

the smallest unit of matter that retains the properties of an element

neutrons

a subatomic particle having no electrical charge, with a mass of about 1.7 times 10 to the negative 24g, found in the nucleus of an atom

protons

a subatomic particle with a single positive electrical charge, with a mass of about 1.7 times 10 to the negative 24g, found in the nucleus of an atom

electrons

a subatomic particle with a single negative electrical charge and a mass about 1 two-thousandths that of a neutron or proton

atomic nucleus

an atom’s dense central core, containing protons and neutrons

dalton

a measure of mass for atoms and subatomic particles; the same as the atomic mass unit, or amu

atomic number

the number of protons in the nucleus of an atom, unique for each element and designed by a subscript

mass number

the total number of protons and neutrons in an atom’s nucleus

atomic mass

the total mass of an atom, numerically equivalent to the mass in grams of 1 mole of the atom

isotope

one of several atomic forms of an element, each with the same number of protons but a different number of neutrons, thus differing in atomic mass

radioactive isotope

an isotope that is unstable; the nucleus decays spontaneously, giving off detectable particles and energy

half-life

the amount of time it takes for 50 percent of a sample of a radioactive isotope to decay

radiometric dating

a method for determining the absolute age of rocks and fossils, based on the half-life of radioactive isotopes

energy

the capacity to cause change, especially to do work

potential energy

the energy that matter possesses as a result of its location or spatial arrangement

electron shells

an energy level of electrons at a characteristic average distance from the nucleus of an atom

valence electrons

an electron in the outermost electron shell

valence shell

the outermost energy shell of an atom, containing the valence electrons involved in the chemical reactions of that atom

orbital

the three-dimensional space where an electron is found 90 percent of the time

chemical bonds

an attraction between two atoms, resulting from a sharing of outer-shell electrons or the presence of opposite charges of the atoms

covalent bond

a type of strong chemical bond in which two atoms share one or more pairs of valence electrons

molecule

two or more atoms held together by covalent bonds

single bond

a single covalent bond; the sharing of a pair of valence electrons by two atoms

double bond

a double covalent bond; the sharing of two pairs of valence electrons by two atoms

valence

the bonding capacity of a given atoms the number of covalent bonds that an atom can form, which usually equals the number of unpairs electrons in its outermost shell

electronegativity

the attraction of a given atom for the electrons of a covalent bond

non-polar covalent bond

a type of covalent bond in which electrons are shared equally between two atoms of similar electronegativity

polar covalent bond

a covalent bond between atoms that differ in electronegativity; the shared electrons are pulled closer to the more electronegative atom, making it slightly negative and the other atom slightly positive

ions

an atom or group of atoms that has gained or lost one or more electrons, thus acquiring a charge

cation

a positively charged ion

anion

a negatively charged ion

ionic bond

a chemical bond resulting from the attraction between oppositely charged ions

ionic compounds

a compound resulting from the formation of an ionic bond

hydrogen bond

a type of weak chemical bond that is formed when the slightly positive hydrogen atom of a polar covalent bond in one molecule is attracted to the slightly negative atom of a polar covalent bond in another molecule or in another region of the same molecule

van de waals interactions

weak attractions between molecules or parts of molecules that result from transient local partial charges

chemical reactions

the making and breaking of chemical bonds, leading to changes in the composition of matter

reactants

a starting material in a chemical reaction

products

a material resulting from a chemical reaction

chemical equailibrium

in a chemical reaction, the state in which the rate of the forward reaction equals the rate of the reverse reaction, so that the relative concentrations of the reactants and products do not change with time

macromolecules

a giant molecule formed by the joining of smaller molecules; include polysaccharides, proteins, and nucleic acids

polymer

a long molecule consisting of many similar or identical monomers linked together by covalent bonds

monomers

the subunit that serves as the building block of a polymer

enzymes

a macromolecule serving as a catalyst, a chemical agent that increases the rate of a reaction without being consumed by the reaction

dehydration reaction

a chemical reaction in which two molecules become covalently bonded to each other with the removal of a water molecule

hydrolysis

a chemical reaction that breaks bonds between two molecules by the addition of water; functions in disassembly of polymers to monomers

carbohydrates

a sugar (monosaccharide) or one of its dimers (disaccharides) or polymers (polysaccharides)

monosaccharides

the simplest carbohydrate; active alone or serving as a monomer for disaccharides and polysaccharides

disaccharide

a double sugar, consisting of two monosaccharides joined by a glycosidic linkage formed by a dehydration reaction

glycosidic linkage

a covalent bond formed between two monosaccharides by a dehydration reaction

polysaccharides

a polymer of many monosaccharides, formed by dehydration reactions

glycogen

an extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch

cellulose

a structural polysaccharide of plant cell walls, consisting of glucose monomers joined by beta glycosidic linkages

chitin

a structural polysaccharide, consisting of amino sugar monomers, found in many fungal cell walls and in the exoskeletons of all arthropods

lipids

any of a group of large biological molecules, including fats, phospholipids, and steroids, that mix poorly, if at all, with water

fat

a lipid consisting of three fatty acids linked to one glycerol molecules

fatty acid

a carboxylic acid with a long carbon chain; three linked to a glycerol molecule form a fat molecule

saturated fatty acid

a fatty acid in which all carbons in the hydrocarbon tail are connected by single bonds, thus maximizing the number of hydrogen atoms that are attached to the carbon skeleton

unsaturated fatty acid

a fatty acid that has one or more double bonds between carbons in the hydrocarbon tail; reduces the number of hydrogen atoms attached to the carbon skeleton

trans fat

an unsaturated fat, formed artificially during hydrogenation of oils, containing one or more trans double bonds

phospholipid

a lipid made up of glycerol joined to two fatty acids and a phosphate group; the hydrocarbon chains of the fatty acids act as non-polar, hydrophobic tails, while the rest of the molecules acts as a polar, hydrophilic head

steroids

a type of lipid characterized by a carbon skeleton consisting of four fused rings with various chemical groups attached

cholesterol

a steroid that forms an essential component of animal cell membranes and acts as a precursor molecule for the synthesis of other biologically important steroids, such as many hormones