FTCE Biology 6-12 key terms

A testable, tentative explanation for an observation or question that predicts a specific outcome and can be supported or rejected by evidence.

The factor a researcher deliberately changes or manipulates in an experiment to observe whether it produces an effect on the measured outcome.

The outcome that is measured in an experiment; it is expected to respond to changes in the factor the researcher manipulates.

A comparison group in an experiment that does not receive the treatment being tested, allowing researchers to attribute observed changes to the treatment rather than other factors.

A broad, well-supported explanation for a large body of evidence that has survived repeated testing and is accepted by the scientific community as the best current account.

The process in which independent experts evaluate a study's methods, data, and conclusions before publication, helping to catch errors and maintain scientific standards.

The two-layer arrangement of molecules that forms cell membranes, with water-attracting heads facing outward and water-avoiding tails facing inward, creating a selective barrier.

The movement of water across a selectively permeable membrane from an area of higher water concentration to one of lower water concentration, driven by differences in solute concentration.

Movement of substances across a membrane against their concentration gradient using energy, typically supplied by ATP and carried out by transport proteins.

A protein that speeds up a chemical reaction by lowering the activation energy needed, without being consumed, and that typically acts on one specific substrate.

Adenosine triphosphate, the molecule cells use as their main energy currency; releasing its terminal phosphate group provides energy for many cellular processes.

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

The set of reactions in cells that break down sugars and other fuels to release energy, which is captured in ATP, with carbon dioxide and water as waste products.

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

The process in which a DNA sequence is copied into messenger RNA inside the nucleus, carrying genetic instructions to the ribosomes for protein building.

The process in which ribosomes read messenger RNA and assemble amino acids into a protein according to the genetic code.

A cell lacking a membrane-bound nucleus and other membrane-bound organelles, found in bacteria and archaea, with its DNA in a single circular chromosome.

A cell that contains a membrane-bound nucleus and other organelles, such as mitochondria and chloroplasts, and makes up organisms in the domain Eukarya.

One of the alternative versions of a gene at a given location on a chromosome; different alleles can produce different observable traits.

The observable characteristics of an organism, such as eye color or height, resulting from the interaction of its genetic makeup with the environment.

A change in the DNA sequence of a gene or chromosome, which may be harmful, neutral, or beneficial and is the original source of new genetic variation.

The process by which individuals with traits better suited to their environment tend to survive and reproduce more, causing those inherited traits to become more common over generations.

A random change in allele frequencies in a population from one generation to the next, especially pronounced in small populations and unrelated to trait advantage.

The transfer of alleles between populations through migration of individuals or movement of gametes, which tends to reduce genetic differences among populations.

The formation of new and distinct species, often when populations become reproductively isolated and accumulate genetic differences over time.

The two-part scientific naming system for species, consisting of the genus name and a specific epithet, both usually italicized with the genus capitalized.

The evolutionary history and relationships among groups of organisms, often depicted as a branching tree showing common ancestry.

Body parts in different species that share a common evolutionary origin and similar underlying structure, even if they perform different functions today.

The independent evolution of similar traits in unrelated species, usually because they face similar environmental pressures, producing analogous rather than homologous structures.

An infectious particle made of genetic material wrapped in a protein coat that cannot reproduce on its own and must use a host cell's machinery.

The maximum population size of a species that an environment can support indefinitely, given the available food, water, space, and other resources.

A species whose influence on its ecosystem is disproportionately large compared with its abundance, so its removal can cause major changes to the community.

A feeding position in a food chain, such as producer, primary consumer, or secondary consumer, defined by how many energy-transfer steps an organism is from the sun.

A close relationship between two species in which both partners benefit, such as flowering plants receiving pollination while pollinators get nectar.

The gradual development of a biological community in an area with no existing soil, such as bare rock after a volcanic eruption or glacial retreat.

The ability of an organism to keep its internal conditions, such as temperature and blood sugar, within stable ranges despite changes in the external environment.

A control mechanism in which a change in a body condition triggers a response that reverses the change and brings the condition back toward its normal range.

A rapid electrical signal that travels along the membrane of a neuron when it is sufficiently stimulated, caused by the flow of sodium and potassium ions.

A behavior that an animal performs correctly the first time without learning, because it is genetically programmed, such as a spider building its web.

A behavior that develops or changes through experience, observation, or practice, rather than being fully present from birth.