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Unit 1


cell The smallest unit that can perform all life processes; cells are covered by a membrane and contain DNA and cytoplasm
stimulus Anything that causes a reaction or change in an organism or any part of an organism
homeostasis The maintenance of a constant internal state in a changing environment
DNA Deoxyribonucleic acid, a molecule that is present in all living cells and that contains the information that determines the traits a living thing inherits and needs to live
sexual reproduction Reproduction in which the sex cells from 2 parents unite to produce offspring that share traits from both parents
asexual reproduction Reproduction that does not involve the union of sex cells and in which one parent produces offspring that are genetically identical to the parent
theory of evolution The process by which inherited characteristics within a population change over generations - this leads to the rise of new species
selective breeding The human practice of breeding animals or plants that have certain desired traits; also called artificial selection
natural selection The process by which individuals that are better adapted to their environment survive and reproduce more successfully than less well-adapted individuals
variation The occurrence of hereditary or non-hereditary differences between different individuals of a population
mutation A change in the nucleotide base sequence of a gene or DNA molecule
adaptation A characteristic that improves an individual’s ability to survive and reproduce in a particular environment
extinction The death of every member of a species
fossil The trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock
fossil record The history of life in the geologic past as indicated by the traces or remains of living things
Created by: jessica.watson