Science Unit Review

Variation

A difference in traits between organisms.

Bell Curve

A graph that shows most of the data falls in an area around the top, considered 'normal'.

DNA (Deoxyribonucleic Acid)

The molecule that contains all the instructions for building a specific organism.

Gene

A part of DNA that contains information controlling a trait.

Chromosome

A structure made up of DNA and genes, located in the nucleus of cells.

Allele

Different forms of a gene represented by letters.

Genotype

The combination of alleles an organism has.

Phenotype

An organism’s physical appearance as a result of its genotype.

Mutation

A change in an organism’s genetic code that can occur during DNA replication.

Natural Selection

A process where organisms with the highest fitness survive and reproduce.

Adaptation

A trait that helps an organism survive and reproduce in its environment.

Selective Breeding

The process of choosing parents for breeding that show desired characteristics.

Genetic Engineering

The manipulation of an organism's genes using biotechnology techniques.

Fitness

An organism’s ability to survive and reproduce in its environment.

Hybridization

Getting a blend of traits by crossing organisms with different characteristics.

Recombination

A process where chromosomes become twisted together and some genes change places.

Inbreeding

Crossing organisms with similar traits to keep desired characteristics.

Protein

Molecules that are built from genes and determine traits.

Nucleotide

The basic building block of DNA, made up of sugar, phosphate, and a base.

Substitution Mutation

A type of mutation where one or more bases are traded.

Insertion Mutation

A type of mutation where one or more bases are added.

Deletion Mutation

A type of mutation where one or more bases are removed.

Domestication

Cultivating wild plants for human use, a form of artificial selection.