BIOL 1406 FLASHCARDS: Exam #1

Domain Archaea

Prokaryotic, single-celled organisms; have cell walls; reproduce using binary fission (duplication); RNA sequence is most similar to Eukarya; live in extreme environments and therefore do not infect humans; oldest life forms; include methanogens, extreme thermophiles, and extreme halophiles

Domain Bacteria

Prokaryotic, single-celled organisms; have cell walls; reproduce using binary fission; differ from archaea in environment and materials in cell wall; includes cyanobacteria

Biology

The scientific study of life and its processes

Biosphere

"Largest ecosystem"; the Earth from atmosphere to core

Cell

An organism's basic unit of structure and function; enclosed by a membrane that regulates the passage of materials between its insides and its surroundings; uses DNA as genetic information

Community

A set of populations in a given area

Consumer

A heterotroph; an organism that obtains organic food molecules by eating other organisms or substances derived from them

Controlled Experiment

An experiment in which an experimental group is compared with a control group that varies only in the factor being tested

Domain Eukarya

All organisms made up of eukaryotic cells; includes the Kingdoms Plantae, Animalia, Fungi, and protists

Emergent Properties

Properties that become apparent as complexity is elevated

Eukaryotic Cell

Has a "true nucleus," and organelles with membranes; is much larger than the other type of cell

Gene

A unit of inheritance; determines physical traits

Genome

The entire genetic library of an organism

Theory

A widely accepted explanation of a biological phenomenon based on sound evidence from rigorous empirical experiments and scientific observations

Hypothesis

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

Inductive Reasoning

Bottom-up approach; a type of logic in which generalizations are based off a number of specific observations; specific to general

Deductive Reasoning

Top-down approach; specific results are predicted from a general premise; general to specific

Kingdom Animalia

A Kingdom of Domain Eukarya; multicellular, includes heterotrophic organisms with no cell wall

Kingdom Fungi

A Kingdom of Domain Eukarya; members have cell walls made of chitin, decompose organic material to obtain nutrients, and digest food outside themselves using enzymes

Kingdom Plantae

A Kingdom of Domain Eukarya; members are photosynthetic, have cell walls made of cellulose, and are multicellular

Positive Feedback

Regulation in which the end product speeds up its own production

Negative Feedback

Regulation in which accumulation of an end product of a process slows that process

Organ/Organ System

Functions as organelles do in cells, serving various purposes in an organism's body

Organelles

Small, usually membranous; located in the cytoplasm of eukaryotic cells

Organisms

Individual living things

Population

All individuals of a species within a given area

Producer

An autotroph; an organism that obtains organic food molecules using energy from the sun or oxidation of inorganic substances

Prokaryotic Cell

A type of cell lacking organelles and a "true nucleus;" found in unicellular organisms

Reductionism

An approach of reducing complex systems into simpler compounds that are more manageable to study; has limitations due to emergent properties

Systems Biology

An approach that attempts to model the dynamic behavior of whole biological systems based on a study of the interactions among the system's parts

Cyanobacteria

Members of Domain Bacteria; photosynthetic; produce oxygen and contain chlorophyll

Atom

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

Atomic Mass

An approximation of the total mass of an atom; measured in daltons

Atomic Nucleus

A dense core at the center of an atom containing protons and neutrons

Atomic Number

The number of protons in an element; written as a subscript

Cation

A positively charged ion

Anion

A negatively charged ion

Chemical Bond

An attraction that holds atoms together

Compound

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

Covalent Bond

The sharing of a pair of valence electrons by two atoms

Electron

A negatively charged subatomic particle

Electron Shells

Levels of differing energy in the electron cloud

Electronegativity

The attraction of a particular atom for the electrons of a covalent bond; the thirstiness of an atom

Element

A substance that cannot be broken down to other substances by chemical reactions

Energy

The capacity to cause change

Energy Level

Another name for an electron shell

Hydrogen Bond

The non-covalent attraction between a hydrogen atom and an electronegative atom; weak chemical bond

Ion

A charged atom

Ionic Bond

Chemical bond that occurs as a result of the transfer of an electron between two elements; usually present between a metal and a nonmetal

Ionic Compounds

Compounds formed by Ionic Bonds; also known as salts

Isotope

Different atomic forms of the same element; has more or less neutrons than usual

Mass Number

The sum of neutrons and protons in an atom; written as a superscript

Matter

Anything that has mass and takes up space

Molecular Formula

A formula giving the number of atoms of each of the elements present in one molecule of a specific compound

Molecule

Two or more atoms held together by covalent bonds

Neutron

A neutral subatomic particle

Nonpolar Covalent Bond

A covalent bond between two elements of the same electronegativity

Orbital

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

Periodic Table of the Elements

A tabular display of the chemical elements

Polar Covalent Bond

A type of covalent bond that occurs when one atom is more electronegative than the other

Potential Energy

The energy that matter possesses because of its location or structure

Proton

Positively charged subatomic particle

Radioactive Isotope

An isotope in which the nucleus decays spontaneously, giving off particles and energy

Structural Formula

A formula that shows the arrangement of atoms in the molecule of a compound

Valence

Number of open electron spots on an atom's valence shell

Valence Electrons

Electrons on an atom's valence shell

Valence Shell

The outermost electron shell of an atom

Van der Waals Interactions

A weak attractive force between atoms or non-polar molecules caused by a temporary change in dipole moment arising from a brief shift of orbital electrons to one side of one atom or molecule, creating a similar shift in adjacent atoms or molecules

Polar Molecule

A molecule consisting of polar covalent bonds; overall charge is unevenly distributed

Cohesion

The tendency of water to be attracted to itself; occurs due to multiple hydrogen bonds

Adhesion

The clinging of one substance to another

Surface Tension

The measure of how difficult it is to break or stretch a liquid

Specific Heat

The amount of heat that must be absorbed or lost for 1 gram of a substance to change its temperature by 1 degree Celsius

Heat of Vaporization

The quantity of heat that a liquid must absorb for 1 gram of it to be converted from the liquid to the gaseous state

Evaporative Cooling

As a liquid evaporates, the surface of the liquid that remains behind cools down - this is known as ____________

Solution

A liquid that is a completely homogenous mixture of two or more substances

Solvent

The dissolving agent of a solution

Solute

The substance in a solution being dissolved

Hydration Shell

The sphere of water molecules around each dissolved ion in a solution

Hydrophyllic

Describes any substance that has an affinity for water

Hydrophobic

Describes any substance that is repelled by water

Hydrogen Ion

A single proton with a charge of 1+

Hydroxide Ion

A water molecule that has lost a proton; has a charge of 1-

Acid

Substance that increases the hydrogen ion concentration of a solution

Base

Substance that decreases the hydrogen ion concentration of a solution

pH

The negative logarithm of the hydrogen ion concentration

Buffer

A substance that minimizes changes in the concentration of H+ and OH- in a solution

Organic Chemistry

Branch of chemistry that specializes in the study of carbon compounds

Hydrocarbons

Organic molecules consisting of only Carbon and Hydrogen atoms

Isomers

Compounds that have the same molecular formula but different structures/properties

Structural Isomers

Isomers that differ in the covalent arrangements of their atoms

Geometric Isomers

Also known as cis-trans isomers; have covalent bonds to the same atoms, but differ in their spatial arrangements due to the inflexibility of double bonds

Enantiomers

Isomers that are mirror images of each other

Functional Groups

Groups of compounds that are important in biological chemical reactions

Hydroxyl Group

In a ____________, a hydrogen atom is bonded to an oxygen atom, which in turn is bonded to the carbon skeleton of the organic molecule; Alcohols; polar (--OH)

Carbonyl Group

A ____________ consists of a carbon atom joined to an oxygen atom by a double bond; Ketones and Aldehydes (which can be structural isomers); found in sugars; polar (>CO)

Carboxyl Group

When an oxygen atom is double bonded to a carbon atom that is also bonded to an --OH group, the entire assembly is called a ____________; Carboxylic Acids or organic acids; acidic; polar (--COOH)

Amino Group

The ____________ consists of a nitrogen atom bonded to two hydrogen atoms and to the carbon skeleton; Amines; basic; polar (--NH2)

Sulfhydryl Group

A ____________ consists of a sulfur atom bonded to an atom of hydrogen; it resembles of hydroxyl group in shape; Thiols; polar (--SH)

Phosphate Group

In the ____________, a phosphorus atom is bonded to four oxygen atoms; one oxygen is bonded to a carbon skeleton; two oxygens carry negative charges; Organic phosphates; polar (--OPO3^2-)