Biology  5/e   Raven/Johnson
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Prokaryotic verses eukaryotic cells: The word "eukaryotic" means having a true nucleus, while the name "prokaryotic" means literally, "before" a nucleus and is understood to mean "without" a nucleus. In addition, prokaryotes lack a membrane bound chloroplast, while photosynthetic eukaryotes having cell walls have chemically simple cell walls. Eukaryotes also have mitochondria, golgi complexes, and endoplasmic reticula, which are lacking in prokaryotes.

Meiosis: In meiosis, homologous chromosomes exchange genetic information and are segregated into different cells. In the second division of meiosis, the chromosomes are split into single chromatid chromosomes that are randomly distributed into different cells.

Major features of evolution: The Theory of Evolution holds that diversity among organisms exists; that some diverse characteristics equip some organisms better than others to compete in struggle for existence; and that the forces of nature bring about a selection of the organisms best fit to survive in its environment. The survivors do not contain the same "mix" as the original population.

Definition of species: Species are groups of organisms that differ in one or more characteristics and do not interbreed extensively if they occur together in nature.

Origin of species: As a result of hereditary adaptive change, populations that are originally identical, eventually become more and more dissimilar. Some populations become different enough that they are recognized as species.

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