Biology 1107 - Chapter 1-7 Test

Ion

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

Valence shell

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

Eukaryotic cell

A cell with a membrane-encloses nucleus and membrane-enclosed organelles.

Mass number

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

Ionic bond

A chemical bond resulting from the attraction between oppositely charged ions

Nonpolar covalent bond

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

Organism

An individual living thing, consisting of one or more cells.

Controlled experiment

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

Inquiry

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

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.

Molecule

Two or more atoms held together by covalent bonds

Gene

The discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses).

Genomics

The systematic study of whole sets of genes (or other DNA) and their interactions within a species, as well as genome comparisons between species.

Cation

A positively charged ion

Technology

The application of specific knowledge for a specific purpose, often involving industry or commerce but also including uses in basic research

Neutron

A subatomic particle having no electrical charge (electrically neutral), with a mass of about 1.7 × 10^-24 g, found in the nucleus of an atom.

Atomic number

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

Van der Waals interactions

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

Single bond

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

Element

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

Inductive reasoning

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

Compound

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

Population

A group of individuals of the same species that live in the same area and interbreed, producing fertile offspring.

Evolution

Descent with modification; the process by which species accumulate differences from their ancestors as they adapt to different environments over time; also defined as a change in the genetic composition of a population from generation to generation.

Theory

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

Potential energy

The energy that matter possesses as a result of its location or spatial arrangement (structure).

Trace element

An element indispensable for life but required in extremely minute amounts.

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.

Chemical reaction

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

Proteome

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

Proteomics

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

Ionic compound

A compound resulting from the formation of an ionic bond; also called a salt

Community

All the organisms that inhabit a particular area; an assemblage of populations of different species living close enough together for potential interaction.

Matter

Anything that takes up space and has mass

Orbital

The three-dimensional space where an electron is found 90% of the time.

Prokaryotic cell

A type of cel lacking a membrane-enclosed nucleus and membrane-enclosed organelles. Bacteria and archaea

Producer

An organism that produces organic compound from CO₂ by harnessing light energy (in photosynthesis) or by oxidizing inorganic chemicals (in chemosynthetic reactions carried out by some prokaryotes)

Independent variable

A factor whose value is manipulated or changed during an experiment to reveal possible effects on another factor (the dependent variable)

Energy

The capacity to cause change, especially to do work (to move matter against an opposing force).

Radioactive isotope

An isotope (an atomic form of a chemical element) that is unstable; the nucleus decays spontaneously, giving off detectable particles and energy

Biosphere

An entire portion of Earth inhabited by life; the sum of all the planet’s ecosystems

Archaea

One of the two prokaryotic domains, the other being Bacteria.

Reactant

The starting material in a chemical reaction.

Atomic nucleus

A atom’s dense central core, containing protons and neutrons.

Bacteria

One of the two prokaryotic domains, the other being Archaea.

Organelle

Any of several membrane-enclosed structures with specialized functions, suspended in the cytosol of eukaryotic cells.

Electron shell

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

Atomic mass

The total mass of an atom, numerically equivalent to the mass in grams of 1 mole of the atom. (For an element with more than one isotope, the _______ is the average mass of the naturally occurring isotopes, weighted by their abundance.)

Bioinformatics

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

Data

Recorded observations

Biology

The scientific study of life.

Dalton

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

Molecule

Two or more atoms held together by covalent bonds

DNA (deoxyribonucleic acid)

A nucleic acid molecule, usually a double-stranded helix, in which each polynucleotide strand consists of nucleotide monomers with a deoxyribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and thymine (T); capable of being replicated and determining the inherited structure of a cell’s proteins.

Hypothesis

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

Organ

A specialized center of body function composed of several different types of tissues.

Atom

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

Double bond

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

Essential element

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

Electronegativity

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

Proton

A subatomic particle with a single positive electrical charge, with a mass of about 1.7 × 10^-24 g, found in the nucleus of an atom.

Consumer

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

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.

Dependent variable

A factor whose value is measured during an experiment or other test to see whether it is influenced by changes in another factor (the independent variable).

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.

Chemical bond

An attraction between two atoms, resulting from a sharing of outer-shell electrons or the presence of opposite charges on the atoms. The bonded atoms gain complete outer electron shells.

Eukarya

The domain that includes all eukaryotic organisms.

Tissue

An integrated group of cells with a common structure, function, or both

Anion

A negatively charged ion

Product

A material resulting from a chemical reaction

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.

Model organism

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

Valence electron

An electron in the outermost electron shell.

Science

An approach to understanding the natural world.

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 of function as RNAs

Chemical equilibrium

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.

Deductive reasoning

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

Feedback regulation

The regulation of a process by its output or end product

Cell

Life’s fundamental unit of structure and function; the smallest unit of organization that can perform all activities required for life.

Covalent bond

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

Systems biology

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

Experiment

A scientific test. Often carried out under controlled conditions that involve manipulating on factor in a system in order to see the effects of changing that factor.

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.

Salt

A compound resulting from the formation of an ionic bond; also called an ionic compound.

Radiometric dating

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

Electron

A subatomic particle with a single negative electrical charge and a mass about 1/2,000 that of a neutron or proton. One or more electrons move around the nucleus of an atom.

Half-life

The amount of time it takes for 50% of a sample of a radioactive isotope to decay.

Climate change

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

Valence

The bonding capacity of a given atom; the number of covalent bonds that an atom can form, which usually equals the number of unpaired electrons in its outermost (valence) shell.

Ecosystem

All the organisms in a given area as well as the abiotic factors with which they interact; one or more communities and the physical environment around them.

Variable

A factor that varies in an experiment

Hydrogen ion

A single proton with a charge of 1+. The dissociation of a water molecule (H2O) leads to the generation of hydroxide ion (OH^-) and a hydrogen ion (H⁺); in water, H⁺ is not found alone but associates with a water molecule to form a hydronium ion.

Joule (J)

A unit of energy J = 0.239 cal; 1 cal = 4.184J

Solute

A substance that is dissolved in a solution

Heat

Thermal energy in transfer from one body of matter to another

Base

A substance that reduces the hydrogen ion concentration of a solution.

Kinetic energy

The energy associated with the relative motion of objects. Moving matter can perform work by imparting motion to other matter.

Calorie (cal)

The amount of heat energy required to raise the temperature of 1 g of water by 1°C. The Calorie (with a capital C), is usually used to indicate the energy content of food, is a kilocalorie.

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.

Buffer

A solution that contains a weak acid and its corresponding base. A buffer minimizes changes in pH when acids or bases are added to the solution.