DC CAPE 2.0 Science Biology key terms

A thin, flexible barrier of lipids and proteins that surrounds every cell and controls which substances move into or out of it.

The net movement of particles from an area where they are more concentrated to one where they are less concentrated, driven by random molecular motion.

The diffusion of water across a selectively permeable membrane, moving from a region of higher water concentration to one of lower water concentration.

A protein that speeds up a specific chemical reaction by lowering the activation energy needed, without being consumed in the reaction.

The specific molecule or molecules that an enzyme binds and chemically transforms during a reaction.

The minimum energy that reacting molecules must possess for a chemical reaction to begin.

The process by which plants, algae, and some bacteria use light energy to convert carbon dioxide and water into sugars, releasing oxygen.

The set of reactions in cells that release energy stored in food molecules, especially glucose, to produce usable ATP.

Adenosine triphosphate, a small molecule that stores and transfers chemical energy for cellular work; releasing its terminal phosphate group supplies energy.

A membrane-bound organelle in eukaryotic cells where most ATP is produced during aerobic respiration.

A green organelle found in plant cells and algae that contains chlorophyll and is the site of photosynthesis.

The process by which a DNA molecule is copied to produce two identical double helices before a cell divides.

Deoxyribonucleic acid, the double-stranded molecule that stores genetic information in the sequence of its nucleotide bases.

A segment of DNA that carries the instructions for making a functional product, usually a protein or RNA molecule.

One of two or more alternative versions of a gene that can occupy the same position on a chromosome.

The particular combination of alleles an organism carries for a given gene or set of genes.

The observable characteristics of an organism, produced by the interaction of its genotype with the environment.

A trait that appears in an organism whenever at least one copy of its controlling allele is present.

A trait that is expressed only when an organism carries two copies of the recessive allele and no dominant allele.

A structure of DNA and associated proteins that carries genes and is passed to daughter cells during cell division.

Cell division that produces two genetically identical daughter cells, used for growth, repair, and asexual reproduction.

A two-stage form of cell division that produces haploid gametes with half the chromosome number of the parent cell.

A change in the nucleotide sequence of DNA that may alter a gene's product and can be inherited if it occurs in gametes.

The process by which individuals with inherited traits that improve survival and reproduction leave more offspring, shifting trait frequencies in a population over generations.

An inherited feature of an organism that increases its ability to survive and reproduce in its environment.

An organism's relative contribution of offspring to the next generation, reflecting how well it reproduces in its environment.

Change over generations in the inherited characteristics of a population, often measured as shifts in allele frequencies.

Body parts in different species that share a common structural origin and underlying anatomy, though they may serve different functions.

A reduced or functionless body part that remains in an organism but had a useful function in an ancestor.

The two-part naming system for species, consisting of a capitalized genus name followed by a lowercase specific epithet, usually italicized.

The science of naming, describing, and classifying organisms into hierarchical groups based on shared characteristics and evolutionary relationships.

A group of organisms that can interbreed and produce fertile offspring under natural conditions; the basic unit of biological classification.

A tool for identifying organisms that presents a series of paired contrasting choices, each leading to another pair or to an identification.

The maximum population size of a species that a given environment can support over the long term given available resources.

Any resource or condition that restricts the growth, abundance, or distribution of a population in an ecosystem.

All the individuals of the same species living in a defined area at the same time.

A network of interconnected food chains that shows how energy and matter move among producers, consumers, and decomposers in an ecosystem.

An organism, usually a photosynthetic plant or alga, that makes its own food and forms the base of a food web.

An organism such as a fungus or bacterium that breaks down dead organic matter, recycling nutrients back into the ecosystem.

The maintenance of a relatively stable internal environment within an organism despite changes in external conditions.

A control mechanism in which a change in a body condition triggers a response that reverses the change, restoring the original state.

A cycle in which the output of a system influences its own activity, either dampening change or amplifying it.

The body system of cells, tissues, and organs that defends against pathogens and other foreign substances.