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Radiometric dating mm lab

The pupil of a human eye is a self-adjusting aperture. archetype: The original form or body plan from which a group of organisms develops.

Amphibian larvae are aquatic, and have gills for respiration; they undergo metamorphosis to the adult form.

Most amphibians are found in damp environments and they occur on all continents except Antarctica.

Also used to describe the process of genetic change within a population, as influenced by natural selection.

adaptive landscape: A graph of the average fitness of a population in relation to the frequencies of genotypes in it.

analogous structures: Structures in different species that look alike or perform similar functions (e.g., the wings of butterflies and the wings of birds) that have evolved convergently but do not develop from similar groups of embryological tissues, and that have not evolved from similar structures known to be shared by common ancestors. Note: The recent discovery of deep genetic homologies has brought new interest, new information, and discussion to the classical concepts of analogous and homologous structures.

amphibians: The class of vertebrates that contains the frogs, toads, newts, and salamanders.The amphibians evolved in the Devonian period (about 370 million years ago) as the first vertebrates to occupy the land.

aperture: Of a camera, the adjustable opening through which light passes to reach the film.amino acid sequence: A series of amino acids, the building blocks of proteins, usually coded for by DNA.Exceptions are those coded for by the RNA of certain viruses, such as HIV.In a diploid cell there are usually two alleles of any one gene (one from each parent).Within a population there may be many different alleles of a gene; each has a unique nucleotide sequence.The diameter of the aperture determines the intensity of light admitted. archeology: The study of human history and prehistory through the excavation of sites and the analysis of physical remains, such as graves, tools, pottery, and other artifacts.