Bio Keystones (copy 124-146)

:(

Population

A group of individuals of the same species living in a specific geographical area and reproducing.

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.

Principle (Scientific)

A concept based on scientific laws and axioms (rules assumed to be present, true, and valid) where general agreement is present.

Producer (Ecological)

An organism that uses a primary energy source to conduct photosynthesis or chemosynthesis.

Prokaryote

A single‐celled organism that lacks a membrane‐bound nucleus and specialized organelles.

Protein

A macromolecule that contains the principal components of organisms: carbon, hydrogen, oxygen, and nitrogen; performs a variety of structural and regulatory functions for cells.

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.

Pumps (Ion or Molecular)

Any of several molecular mechanisms in which ions or molecules are transported across a cellular membrane requiring the use of an energy source (e.g., glucose, sodium [Na+], calcium [Ca+], and potassium [K+]).

Punctuated Equilibrium

A proposed explanation in evolutionary biology stating that species are generally stable over long periods of time. Occasionally there are rapid changes that affect some species which can quickly result in a new species.

Recessive Inheritance

A pattern of inheritance in which the phenotypic effect of one allele is only expressed within a homozygous genotype. In a heterozygous condition with a dominant allele, it is not expressed in the phenotype.

Ribosome

A cellular structure composed of RNA and proteins that is the site of protein synthesis in eukaryotic and prokaryotic cells.

Science

A body of evidence‐based knowledge gained through observation and experimentation related to the natural world and technology.

Selective Breeding

The process of breeding organisms that results on offspring with desired genetic traits.

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.

Sex‐linked Trait

A trait, associated with a gene that is carried by either the male or female parent (e.g., color blindness and sickle‐cell anemia).

Speciation

A process typically caused by the genetic isolation from a main population resulting in a new genetically distinct species.

Species

The lowest taxonomic level of biological classification consisting of organisms capable of reproduction that results in fertile offspring.

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.

Succession

A series of predictable and orderly changes within an ecosystem over time.

Symbiotic Relationship

A relationship between two organisms (i.e., mutualism, in which both organisms benefit; parasitism, in which one organism benefits and the other organism is harmed; and commensalism, in which one organism benefits and the other organism does not benefit or is not harmed).

System

A set of interacting or interdependent components, real or abstract, that form an integrated whole. An open system is able to interact with its environment. A closed system is isolated from its environment.

Temperature

A measure of the average kinetic energy (energy of motion) of particles in a sample of matter. This physical property can determine the rate and extent to which chemical reactions can occur within living systems. It is commonly measured in degrees Celsius (°C) or Fahrenheit (°F).

Terrestrial

A term that describes an organism associated with a land environment.

Theory (Scientific)

(proven)description of why thing happen

Tissue

An anatomical unit composed of cells organized to perform a similar function.

Transcription

The process in which a strand of messenger RNA (mRNA) is synthesized by using the genetic information found on a strand DNA as a template.