EVOLUTION REVIEW DOMAINS BACTERIA PROKARYOTE Domain Bacteria is

EVOLUTION REVIEW

DOMAINS

BACTERIA (PROKARYOTE) � Domain Bacteria is composed of organisms that are much more common than Archaea and live almost anywhere. There are more bacteria in a person's mouth than there are people in the world. Many are decomposers, some are photosynthesizers, and a few cause disease. Most bacteria cause disease by producing exotoxins that harm human cells, while others cause illness as a result of glycoproteins found on the outside of their capsules. The bacteria in this group are helically shaped and usually are found alone. They can reach. 5 mm long but are extremely thin.

BACTERIA

ARCHEAE (PROKARYOTE) � Domain Archaea is mostly composed of cells that live in extreme environments. While they are able to live elsewhere, they are usually not found there because outside of extreme environments they are competitively excluded by other organisms. It is believed that Archaea are very similar to prokaryotes that inhabited the earth billions of years ago. It is also believed that eukaryotes evolved from Archaea. Therefore, it is believed that the domains Archaea and Bacteria branched from each other very early in history, and membrane infolding produced eukaryotic cells in the archaean branch approximately 1. 7 billion years ago.

ARCHAEA

EUKARYOTA � The Domain Eukarya arose from the first prokaryotic organisms more than 1. 7 billion years ago. It includes all of the organisms with eukaryotic cells--that is, those with membranous organelles (including mitochondria and chloroplasts). The organisms in this domain will be the focus of our classifications; indeed, they represent the vast majority of organisms we see each day.

KINGDOMS � BACTERIA: � Prokaryote � Single celled i. e. : bacteria(yogurt), streptococci (strep throat) � ARCHAEA: � Prokaryote � Single celled � Extremeophiles: Thermophiles, methanogens, halophiles

KINGDOMS � PROTISTA: � Eukaryote � Multicellular & Single Celled � Mainly Heterotrophs, but a few are autotrophs � Not bacteria, Not animals, Not plants Slime molds, algae, diatoms

KINGDOM � FUNGI: � Eukaryote � Multicellular � Heterotroph

KINGDOM � PLANTAE: Eukaryotes Multicellular Autotroph

KINGDOM � Animalia � Eukaryote � Multicellular � Heterotroph

EVOLUTION � Evolution: The process of biological change by which descendents come to differ from their ancestry. � � ORIGINS OF LIFE: Endosymbiotic Theory: is the accepted mechanism for how eukaryotic cells evolved from prokaryotic cells. � Chemical Evolution: primordial soup or synthesis of organic molecules. � The early Earth had a chemically reducing atmosphere. This atmosphere, exposed to energy in various forms, produced simple organic compounds ("monomers"). These compounds accumulated in a "soup", which may have been concentrated at various locations (shorelines, oceanic vents etc. ). By further transformation, more complex organic polymers – and ultimately life – developed in the soup.

EVIDENCE OF EVOLUTION � All shows signs of common ancestry � Comparative Anatomy: � Homologous structures, Analogous Structures, & Vestigial Structures

EVIDENCE OF EVOLUTION � � Comparative Embryology: A. There is usually a difference in form between embryo and adult. B. Serial structures (e. g. , segments, limbs) are usually identical in the embryo, but specialized and diverged in the adult. C. Different species in the same Class (e. g. , mammals) often have very similar embryos, even if the adult forms are quite different. D. Embryonic structure is unrelated to "conditions of existence", unless the embryo is active (e. g. , feeding) E. Embryos are sometimes more highly "organized" than adults (e. g. , some parasitic forms).

EVIDENCE OF EVOLUTION � COMPARATIVE EMBRYOLOGY: Common Ancestry

EVIDENCE OF EVOLUTION � FOSSILS: Traces of organisms that existed in the past. � How the structure & form has evolved over time. � We compare older fossils to more recent or modern examples.

EVIDENCE OF EVOLUTION � MOLECULAR EVIDIENCE: � DNA usually over rules everything else to prove/disprove evidence of evolution.

MECHANISMS OF EVOLUTION � GENE FLOW: � Movement of Alleles from one population to another. Movement between populations Increases genetic variation � GENETIC DRIFT: Allele frequencies can change due to chance alone, could lead to extinction.

MECHANISMS OF EVOLUTION � SEXUAL SELECTION: Certain traits increase mating selection. � Bigger tail = more females=more offspring � Prettier song=more females=more offspring � Very specific strips=more females=more offspring � **(wrong stripes=no females=no offspring)

MECHANISMS OF EVOLUTION � � NATURAL SELECTION: Certain traits maybe an advantage for survival. Alleles for these traits increase in frequency. Darwin’s beak- adapt and evolve to survive food differences. The small beaks had to adapt/evolve or they would become extinct.

MECHANISMS OF EVOLUTION � BIOGEOGRAPHY: � Physical barriers that divide a population into 2 or more groups (speciation).

GENETIC VARIATION � MUTATION: � � Random change of the DNA of a gene. RECOMBINATION: � New allele combination � Increases variation which helps a species adapt/evolve. � Small populations limit genetic variation. Limit the gene pool= less ability to adapt/evolve. Even leading to possible extinctionl.