Term | Definition |
Allele | different forms of a gene for each variation of a trait of an organism |
Dominant | observed trait of an organism that mask the recessive form of a trait; these alleles show their effect on the phenotype whenever they are present in the genotype |
Genetics | study of heredity |
Genotype | combination of genes in an organism, genetic makeup |
Heredity | passing on of characteristics from parents to offspring |
Heterozygous | an organism has two different alleles for a trait; hybrid |
Homozygous | an organism has two identical alleles for a trait; pure |
Phenotype | a combination of the organism's genetic makeup and the environment's effect on that makeup; physical appearance |
Recessive | trait of an organism that can be masked by the dominant form of a trait |
Trait | characteristic that is inherited; can be either dominant or recessive |
Gene | part of the DNA code on a chromosome; controls traits |
Homozygous Dominant | two dominant alleles; BB |
Heterozygous | one dominant & one recessive allele; Bb |
Homozygous Recessive | two recessive alleles; bb |
Probability | likelihood that a particular event will occur |
Punnett Square | calculates all the genotypes of the offspring of a genetic cross; possible outcomes |
Mutation | a change in the DNA (genes) of an organism |
Evolution | change in a species over a long period of time |
Species | a group of similar organisms that can mate with one another and produce fertile offspring |
Extinction | the demise of a species; no more living memebers |
Natural Selection | organisms that are better suited to their environment survive and reproduce at a greater rate than organisms that are not |
Adaptive Radiation | production of several species from one ancestral species |
Mendel | worked with pea plants; determined parents passed on one allele each to offspring; responsible for principle of independent assortment and law of segregation |
Independent Assortment | traits are inherited independently of one another |
Law of Segregation | a parent passes one allele for each trait to their offspring |
adaptation | behavior or structure that helps an organism survive |
Sex Cells (gametes) | contain half the normal number of chromosomes, in human 23 |
Behavioral Adaptations | things (actions) organisms do to survive |
Structural Adaptations | physical features of an organism |
Deceptive Coloration | when an organism's color fools either its predators or prey |
Advertising Coloration | when animals and plants use color to be noticed (can be used to warn or attract animals) |
Camouflage | helps an organism blend in with its surroundings |
Mimicry | protects animals and plants from predators or hides them from prey because they look like other things |
Estivation | period of inactivity during dry, hot conditions |
Hibernation | period of inactivity during cold conditions |