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Terms to help pass the science OST

Behavioral Isolation Differences in behavior prevent mating
Population Equilibrium When the same number of individuals die as are born each year
Gene Pool The sum of all genes within a population
Genetic Drift The random change in a gene's allele frequency over time
Habitat The environment where a species lives
Habitat Isolation An isolating mechanism in which two species occupy different habitats within the same general area
Hybrid The result of two species mating together
Interbreeding Mating or reproducing with one another
Mutations Sudden changes in an organism’s DNA
Population A group of individuals of the same species living in the same location, capable of reproduction
Species A specific type of organism, containing one or more populations
Stabilizing Selection Natural selection that prevents overall changes in populations
Natural Selection Process where organisms with favorable traits are more likely to reproduce.
Genetic Isolation The lack of interbreeding of organisms within a species
Aerobic Any process that uses oxygen
Anaerobic Any process that does not need oxygen
Prokaryotes Single cell organisms without a nucleus
Eukaryotes Organisms whose cells contain a nucleus
Organelles Small units inside a cell with various functions
Permeable Allowing things through
Passive Transport The passage of molecules through the membrane, not requiring energy
Active Transport The passage of molecules through the membrane that requires energy
Diffusion The passage of molecules from a high concentration to a low concentration
Semi-permeable Allowing some substances through but not others
Asexual Reproduction Reproduction using only one parent; exact copies of the parent are made
Sexual Reproduction Reproduction that combines the genes from two parents to produce offspring
Mitosis The splitting of a cell involving many chromosomes; an exact copy of the cell is made
Meiosis The splitting of sex cells in which the chromosome number is cut in half; eggs/sperm are eventually produced
Cytokinesis The actual splitting of the cells
Diploid Containing two sets of chromosomes (2n)
Haploid Containing only one set of chromosomes (n)
Blending A theory of inheritance that says that offspring receive a mixture of the parents’ characteristics
Self-pollination Fertilizing oneself; the egg and the sperm are created from one plant
Pollination The process of fertilization in plants
Dominant Traits that are expressed even when another gene is present
Recessive Traits that are not expressed when a dominant trait is present
Law of Dominance If two genes are present, only the dominant trait is expressed
Law of Segregation For each trait, two types of genes are present: one from the mother and one from the father
Monohybrid Cross The mating of two parents in which only one trait is tracked
Generation A group of offspring that are approximately the same age
Probability The chance of an event occurring
Punnett Square The chance of an event occurring
Alleles The forms of genes that produce different appearances
Homozygous Containing two of the same alleles
Heterozygous Containing two different alleles
Genotype The genetic makeup of an organism
Phenotype An organism’s expressed trait
Dihybrid Cross A cross that examines two traits at the same time
Autotroph An organism capable of making organic substances from inorganic source (Can make own food)
Heterotroph An organism that can’t synthesize its own food and depends on autotrophs
Homeostasis Maintaining a stable environment
Phylogeny Relating organisms by their evolutionary similarities
Taxonomy The practice and science of classification
Binomial Nomenclature The system of nomenclature in which two terms are used to denote a species of living organism (genus and species)
Binary Fission Process by which all bacteria reproduce
Genome The whole DNA makeup of an organism
Carrying Capacity The number of organisms that can survive in a given environment.
Created by: ScienceOST



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