BIOLOGY KEYSTONE VOCAB - All Terms
nucleic acid
A biological macromolecule composed of the elements C, H, N, O and P that carries genetic information
deoxyribonucleic acid
A biological macromolecule that encodes the genetic information for living organisms and is capable of self-replication and the synthesis of RNA
science
A body of evidence-based knowledge gained through observation and experimentation related to the natural world and technology
ribosome
A cellular structure composed of RNA and proteins that is the site of protein synthesis in eukaryotic and prokaryotic cells
genetic drift
A change in the allele frequency of a population as a result of chance events rather than natural selection
chromosomal mutation
A change in the structure of a chromosome
food web
A complex arrangement of interrelated food chains illustrating the flow of energy between interdependent organisms
cellular respiration
A complex set of chemical reactions involving an energy transformation where potential chemical energy in the bonds of "food" molecules is released and partially captured in the bonds of ATP molecules
principle
A concept based on scientific laws and axioms where general agreement is present
founder effect
A decrease in genetic variation caused by the formation of a new population by a small number of individuals from a larger population
organism
A form of life; an animal, plant, fungus, protist or bacterium
population
A group of individuals of the same species living in a specific geographical area and reproducing
biological macromolecules
A group of large molecules that interact with biological systems and their environments
plastids
A group of membrane-bound organelles commonly found in photosynthetic organisms and mainly responsible for the synthesis and storage of food
biome
A large area or geographical region with distinct plant and animal groups adapted to that environment
carbohydrate
A macromolecule that contains atoms of carbon, hydrogen, and oxygen in a 1:2:1 ratio and serves as a major source of energy for living organisms
protein
A macromolecule that contains the principle components of organisms: C, H, O, and N
temperature
A measure of the average kinetic energy of particles in a sample of matter
mitochondrion
A membrane-bound organelle found in most eukaryotic cells; site of cellular respiration
nucleus
A membrane-bound organelle in eukaryotic cell functioning to maintain the integrity of the genetic material and, through the expression of that material, controlling and regulating cellular activities
energy pyramid
A model that illustrates the biomass productivity at multiple trophic levels in a given ecosystem
organic molecule
A molecule containing carbon that is part of or produced by living systems
monomer
A molecule of any compound that can react with other molecules of the same or different compound to form a polymer
adenosine triphosphate
A molecule that provides energy for cellular reactions and processes
gene recombination
A natural process in which a nucleic acid (usually DNA but can be RNA) is broken and then joined to a different molecule; result of crossing-over
mitosis
A nuclear division resulting in the production of two somatic cells having the same genetic complement as the original cell
dominant inheritance
A pattern of inheritance in which the phenotypic effect of one allele is completely expressed within a homozygous and heterozygous genotype
recessive inheritance
A pattern of inheritance in which the phenotypic effect of one allele is only expressed within a homozygous genotype
co-dominance
A pattern of inheritance in which the phenotypic effect of two alleles in a heterozygous genotype express each phenotype of each allele fully and equally
incomplete dominance
A pattern of inheritance in which two alleles, inherited from the parents, are neither dominant nor recessive
mutation
A permanent transmissible change of genetic material
homologous structure
A physical characteristic in different organisms that is similar because it was inherited from a common ancestor
vestigial structure
A physical characteristic in organisms that appears to have lost its original function as a species has changed over time
analogous structure
A physical structure, present in multiple species, that is similar in function but different in form and inheritance
macromolecule
A polymer with a high molecular mass; four categories: carbohydrates, lipids, nucleic acids, and proteins
natural selection
A process in nature in which organisms possessing certain inherited traits are better able to survive and reproduce compared to others of their species
endocytosis
A process in which a cell engulfs extracellular material through an inward folding of its plasma membrane
exocytosis
A process in which a cell releases substances to the extracellular environment by fusing a vesicular membrane with the plasma membrane, separating the membrane at the point of fusion and allowing the substance to be released
cloning
A process in which a cell, cell product, or organism is copied from an original source
energy transformation
A process in which energy changes from one form to another form while some of the energy is lost to the environment
evolution
A process in which new species develop from preexisting species
photosynthesis
A process in which solar radiation is chemically captured by chlorophyll molecules and through a set of controlled chemical reactions resulting in the potential chemical energy in the bonds of carbohydrate molecules
facilitated diffusion
A process in which substances are transported across a plasma membrane with the concentration gradient with the aid of carrier proteins; require no energy
speciation
A process typically caused by the genetic isolation from a main population resulting in a new genetically distinct species
gradualism
A proposed explanation in evolutionary biology stating that new species arise from the result of slight modifications over many generations
punctuated equilibrium
A proposed explanation in evolutionary biology stating that species are generally stable over long periods of time with occassionaly rapid changes resulting in new species
hypothesis
A proposed, scientifically testable explanation for an observed phenomenon
enzyme
A protein that increases the rate of a chemical reaction without being changed by the reaction; a catalyst
homeostatic mechanism
A regulatory mechanism that contributes to maintaining a state of equilibrium
symbiotic relationship
A relationship between two organisms
gene
A sequence of nucleotides composing a sement of DNA that provides a blueprint for a specific hereditary trait
succession
A series of predictable and orderly changes within an ecosystem over time
system
A set of interacting or interdependent components, real or abstact, that form an integrated whole
food chain
A simplified path illustrating the passing of potential chemical energy (food) from one organism to another organism
chromosomes
A single piece of coiled DNA and associated proteins found in linear forms in the nucleus of eukaryotic cells and circular forms in the cytoplasm of prokaryotic cells
point mutation
A single-base substitution causing the replacement of a single-base nucleotide with another nucleotide
prokaryote
A single-celled organism that lacks a membrane-bound nucleus and specialized organelles
gamete
A specialized cell (egg or sperm) used in sexual reproduction containing half the normal number of chromosomes of a somatic cell
nonnative species
A species normally living outside a distribution range that has been introduced through either deliberate or accidental human activity
endemic species
A species that is found in its originating location and is generally restricted to that geographic area
catalyst
A substance that enables a chemical reaction to proceed at a usually faster rate or under different conditions than otherwise possible without being changed by the reaction
organelle
A subunit within a cell that has a specialized function
ecosystem
A system composed of organisms and nonliving components of an environment
genetic engineering
A technology that includes the process of manipulating or altering the genetic material of a cell resulting in desirable functions or outcomes that would not occur naturally
biotic
A term that describes a living or once-living organism in an ecosystem
abiotic
A term that describes a nonliving factor in an ecosystem
terrestrial
A term that describes an organism associated with a land environment
aquatic
A term that describes an organism assoiciated with a water environment
extinction
A term that typically describes a species that no longer has any known living individuals
endosymbiosis
A theorized process in which early eukaryotic cells were formed from simpler prokaryotes
plasma membrane
A thin, phospholipid and protein molecule bilayer that encapsulates a cell and controls the movement of materials in and out of the cell through active or passive transport
polygenic trait
A trait in which the phenotype is controlled by two or more genes at different loci on different chromosomes
sex-linked trait
A trait, associated with a gene that is carried by either the male or female parent
meiosis
A two-phase nuclear division that results in the eventual production of gametes with half the normal number of chromosomes
gene splicing
A type of gene recombination in which the DNA is intentionally broken and recombined using laboratory techniques
eukaryote
A type of organism composed of one or more cells containing a membrane-bound nucleus, specialized organelles in the cytoplasm, and a mitotic nuclear division cycle
allele
A variation of a gene's nucleotide sequence (an alternative form of a gene)
organ system
An anatomical system composed of a group of organs that work together to perform a specific function or task
tissue
An anatomical unit composed of cells organized to perform a similar function
organ
An anatomical unit composed of tissues serving a common function
habitat
An area that provides an organism with its basic needs for survival
crossing-over
An exchange of genetic material between homologous chromosomes during prophase I of meiosis; contributes to genetic variation
theory
An explanation of observable phenomena based on available empirical data and guided by a system of logic that includes scientific laws
Golgi apparatus
An organelle found in eukaryotic cells responsible for the final stages of processing proteins for release by the cell
chloroplast
An organelle found in plant cells and the cells of other photosynthetic organisms where photosynthesis occurs
endoplasmic reticulum
An organelle, containing folded membranes and sacs, responsible for the production, processing, and transportation of materials for use inside and outside a eukaryotic cell; two types rough and smooth
consumer
An organism that obtains energy by feeding on other organisms or their remains
decomposer
An organism that obtains nutrients by consuming dead and decaying organic matter which allows nutrients to be accessible to other organisms
producer
An organism that uses a primary energy source to conduct photosynthesis or chemosynthesis
genetically modified organism
An organism whose genetic material has been altered through some genetic engineering technology or technique
pumps
Any of several molecular mechanisms in which ions or molecules are transported across a celllular membrane requiring the use of an energy source
biotechnology
Any procedure or methodology that uses biological systems or living organisms to develop or modify either products or processes for specific use
community
Different populations of organisms interacting in a shared environment
isolating mechanisms
Features of behaviors, morphology, or genetics which serve to prevent mating or breeding between two different species
intracellular
Located inside a cell
extracellular
Located outside a cell
unicellular
Made up of a single cell
multicellular
Made up of more than one cell
multiple alleles
More than two forms of a gene controlling the expression of a trait
impermeable
Not permitting passage of a substance or substances
carrier (transport) protein
Proteins embedded in the plasma membrane involved in the movement of ions, small molecules, and macromolecules into and out of cells
frameshift mutation
The addition (insertion) or removal (deletion) of one or more nucleotides that is not indivisible by three, therefore resulting in a completely different amino acid sequence than would be normal
agriculture
The artificial cultivation of food, fiber, and other goods by the systematic growing and harvesting of various organisms
cell
The basic unit of structure and function for all living organism
embryology
The branch of zoology studying the early development of living things
biochemical conversion
The changing of organinc matter into other chemical forms such as fuels
mechanism
The combination of components and processes that serve a common function
cytokinesis
The final phase of a cell cycle resulting in the division of the cytoplasm
genotype
The genetic composition of an organism with reference to a single trait, a set of traits, or the entire complement of traits of an organism
concentration gradient
The graduated difference in concentration of a solute per unit distance through a solution
gene therapy
The intentional insertion, alteration, or deletion or genes within an individual's cells and tissues for the purpose of treating a disease
cohesion
The intermolecular attraction between like molecules
adhesion
The intermolecular attraction between unlike molecules
interphase
The longest-lasting phase of the cell cycle in which a cell performs the majority of its functions, such as preparing for nuclear division and cytokinesis
species
The lowest taxonomic level of biological classification consisting of organisms capable of reproduction that results in fertile offspring
pH
The measure of acidity and alkalinity of an aqueous solution scaling from 1 to 14
concentration
The measure of the amount or proportion of a given substance when combined with another substance
specific heat
The measure of the heat energy required to increase the temperature of a unit quantity of a substance by a certain temperature interval
allele frequency
The measure of the relative frequency of an allele at a genetic locus in a population
biogeochemical cycles
The movement of abiotic factors between the living and nonliving components within ecosystems
diffusion
The movement of particles from an area of high concentration to an area of low concentration
active transport
The movement of particles from an area of low concentration to an area of high concentration that uses energy provided by ATP or a difference in electrical charges across a cell membrane
osmosis
The movement of water or another solvent through permeable membranes from an area of higher water concentration (dilute) to an area of lower water concentration (concentrated)
phenotype
The observable expression of a genotype
migration
The permanent movement of genes into or out of a population resulting in a change in allele frequencies
trophic level
The position of an organism in relation to the flow of energy and inorganic nutrients through an ecosystem
fossils
The preserved remains of traces of organisms that once lived on Earth
DNA replication
The process in which DNA makes a duplicate copy of itself
gene expression
The process in which a nucleotide sequence of a gene is used to make a functional product such as a protein or RNA
translocation
The process in which a segment of a chromosome breaks off and attaches to another chromosome
transcription
The process in which a strand of messenger RNA is synthesized by using the genetic information found on a strand DNA as a template
protein synthesis
The process in which amino acids are arranged in a linear sequence through the processes of transcription of DNA and to RNA and the translation of RNA to a polypeptide chain
inheritance
The process in which genetic material is passed from parents to their offspring
nondisjunction
The process in which sister chromatids fail to separate during and after mitosis or meiosis
semiconservative replication
The process in which the DNA molecule uncoils and separates into two strands; each original strand becomes a template on which a new strand is constructed resulting in two DNA molecules identical to the original DNA molecule
translation
The process in which the messenger RNA molecule on a ribosome is decoded to produce a sequence of amino acids for protein synthesis
selective breeding
The process of breeding organisms that results on offspring with desired genetic traits
homeostasis
The regulatory process in which an organism regulates its internal environment
forensics
The science of tests and techniques used during the investigation of crimes
genetics
The scientific study of inheritance
biology
The scientific study of life
cell cycle
The series of events that take place in a cell leading to its division and duplication
molecule
The smallest particle of a substance that retains the chemical and physical properties of the substance and is composed of two or more atoms held together by chemical forces
atom
The smallest unit of an element that retains the chemical and physical properties of that element
bioenergetics
The study of energy flow (energy transformations) into and within living systems
population dynamics
The study of short- and long-term changes in the number of individuals for a given population, as affected by birth, death, immigration, and emigration
ecology
The study of the relationships between organisms and their interactions witht the environment
freezing point
The temperature at which a liquid changes state to a solid
environment
The total surroundings of an organism or a group of organisms
passive transport
The transportation of materials across a plasma membrane without using energy
biosphere
The zone of life on Earth
competition
When individuals or groups of organisms compete for similar resources such as territory, mates, water, and food in the same environment