PSA.1 sp18 - Chapter 21 Objectives: The Origin and Evolutionary History of Life Chapter 18 PDF

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Chapter 21 Objectives: The Origin and Evolutionary History of Life
Chapter 18 Objectives: Introduction to Darwinian Evolution
Chapter 19 Objectives: Evolutionary Change in Populations
Chapter 20 Objectives: Speciation and Macroevolution
Chapter 22 Objectives: The Evolutio...

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Pre-Session Assignments (PSA) #1 Complete the vocabulary-matching sections and at least the first three objectives for each chapter. Doing so will prepare you for recitations and for the quizzes. You are highly encouraged to complete the rest of the objectives to keep you on track and so you can ask for clarification during recitation. All answers can be found in the textbook, even if a section has not yet been covered in lecture. Please print, complete, and bring to recitation. Chapter 21 Objectives: The Origin and Evolutionary History of Life __D_ an organism that lives in or on another __B_ a specific type of protobiont containing enzymes used for more complex synthesis _C__ single membrane organelles originated by budding off the internal surface of the plasma membrane __E_ double membrane organelles arose from a symbiotic relationship in which the endosymbiont living inside the cell lost its autonomy and became incorporated as an organelle within that cell __G_ one type of protobiont; produced by adding water to abiotically formed polypeptides __F_ an organism not capable of producing its own organic molecules from inorganic materials (will be a consumer) __H_ a vesicle of abiotically produced polymers _A__ an organism capable of producing its own organic compounds from inorganic materials (photosynthesis for example) __I_ a column of prokaryote cells that become fossilized (living ones are extremely rare)

A. Autotroph B. Coacervate C. Endomembranous Theory D. Endosymbiont E. Endosymbiosis Theory F. Heterotroph G. Microsphere H. Protobiont I. Stromatolite

1. Describe the early conditions on early Earth and the requirements for life to begin Gasses such as CO2, N2 and H2S were abundantly present. For the formation of organic molecules to for you need a reactive surface such as pyrite or clay. The enzyme like features attract monomers that will spontaneously polymerize. These organic precursors formed neat thermal vents where colonies of tube worms now live today.

2. Describe the Miller-Urey experimental model and explain how it could be used to investigate the synthesis of organic molecules (drawing helpful!) The Miller-Urey experiment was meant to model the conditions on primitive earth. This was replicated by using a close system that represented the water cycle, also including a spark chamber, water, methane, hydrogen, and ammonia. Over time amino acids formed.

3. Compare and contrast protobionts, microspheres, and coacervates, and discuss their relationship to the hypothesis of “pre-cell life” All are contained in a sphere. Coacervates are the closest structure to a cell and are held together by electrostatic forces. All of these are basic cells. Protobions are abiotically produced molecules self-assemble 1

into a sphere that contains water and is a precursor to cells. Microspheres are proteinoid from the sphere and is enclosed in water and inorganic material.

4. Describe how naturally occurring surfaces may have contributed to early chemical reactions and compare and contrast prebiotic soup hypothesis with iron-sulfur hypothesis for the evolution of protobionts and cells Pyrite and clay have enzyme-like features that attract monomers that can spontaneously polymerize. The ironsulfur hypotheses- energy rich molecules and precursors of biological molecules. Prebiotic soup- water was a “sea of organic soup”.

5. Define the terms associated with the evolution of early life (anaerobe, aerobe, heterotroph, autotroph) Anaerobic- survives in absence of oxygen, Aerobe- requires oxygen, Heterotroph- ingests previously forms material, Autotroph- synthesize own organic nutrients from inorganic molecules

6. Describe the requirements preceding the origin of cells and life Four requirements for chemical evolution- little of no free oxygen so atmosphere was reducing environment, energy source was lightning cosmic and ultraviolet radiation, chemical building blocks including water dissolved inorganic molecules and atmospheric gases were present, time

7. Outline the major steps hypothesized to have occurred in the origin of cells and discuss which order might be correct (RNA first, DNA first, metabolism first, DNA/RNA/Protein) We already know that they can spontaneously form on clay. Proteins first would allow organized and directed synthesis of RNA and DNA. RNA-first hypothesis: self-replicating RNA arose first making ribozymes and RNA replication and eventually chemical reactions in cells, the role for proteins synthesized by ribosomes. Most likely RNA came first.

8. Describe stromatolites and discuss their significance in the evolution of early cells Stromatolites are microfossils, minute layers of prokaryotic cells, fossil evidence of early cells, some still living. These were thought to be the first cells.

9. Describe the first cells and the transformation from an anaerobic to an aerobic environment

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10. Compare and contrast the autogenesis (endomembranous) and serial endosymbiosis theories relating them to the evolution of eukaryotic cells and cellular organelles and discuss evidence that organelles arose from an endosymbiotic relationship with eubacteria Autogenesis theory is as single membrane organelles inward budding of plasma membranes. Serial endosymbiosis once free-living prokaryotes phagocytized and lost independent existence. Organelles arose from these relationship: chloroplasts- photosynthetic bacteria engulfed by heterotrophic cells, mitochondria- aerobic bacteria initially engulfed by anaerobic cells.

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Chapter 18 Objectives: Introduction to Darwinian Evolution _B_ major evolutionary changes that occur over a long period of time resulting in large phenotypic changes such as the formation of new species _E__ a group of individuals of the same species __F_ a group of successfully interbreeding organisms that also produce fertile offspring _C_ more-minor evolutionary changes that occur over just a few generations __G_ remnants of structures that were present and functional in the ancestral organisms __A_ organisms evolved similar characteristics as a result of exposure to similar environmental challenges (natural selection) __D_ an explanation of evolution that incorporates many aspects of biology such as molecular genetics, phylogeny, natural selection, mutations, etc.

A. Convergent Evolution B. Macroevolution C. Microevolution D. Modern Synthesis E. Population F. Species G. Vestigial Structure

1. Name several historical figures and describe their contribution to views on classification and evolution Leonardo da Vince- recognized fossils as extinct animals/organisms Hutton- gradualism, could find intermediates Cuvier- punctuated equilibrium, caused by mass extinction Lamarck- acquired characteristics, use vs. disuse, first indication of theory of evolution, natural selecion

2. Name and explain Darwin’s four premises of evolution by natural selection 1.Varation- individuals in a population exhibit variation in traits, some improve chances of survival and reproductive success. 2. Overproduction- each generation can produce more than can survive. 3. Limits on population growth- competition for limited resources, not all survive to reproduce. 4. Differential reproductive success- survival of the fittest, individuals with most favorable combination of characteristics more likely to survive and reproduce 3. Describe the modern synthesis and how it impacts views on evolution Modern synthesis is the fusion of mendelian and Darwinian theory of evolution. It impacted the views of evolution because it emphasized the importance of genetics in evolution.

4. Define the terms population, species, and evolution Population- a group of individuals of the same species, species- a group of successfully interbreeding that also produce fertile offspring, evolution- similar organisms capable of interbreeding and producing offspring. 5. Compare and contrast the ideas of Darwin, Lamarck, and Wallace Darwin- variation, overproduction, limits on population growth, differential reproductive success Lamarck- acquired characteristics, use vs. disuse, first indication of theory of evolution, natural selection Wallace6. Compare and contrast the various forms of evidence supporting evolution (e.g. fossil record, homology, homoplasy, vestigial structures, and molecular and development homologies) Bias fossil record: favored-organisms that die is aquatic/marine environments such as bogs and tar pits, Not favored- dry environments, rainforests, organisms rapidly decay so they rarely fossilize 4

Chapter 19 Objectives: Evolutionary Change in Populations __H_ a change in allele frequencies from one generation to the next __F_ when a small group of individuals starts a new colony and the new population arises from that original group; as a result, the group exhibits little genetic variation __G_ works to preserve balanced polymorphism; occurs when the heterozygote has a higher level of fitness than either homozygote _M__ natural selection selects against one of the phenotypic extremes and favors the intermediates and other phenotypic extreme __I_ genetic variation among individuals of a population __B_ an event that rapidly, randomly, and dramatically decreases the size of a population _K__ works to preserve balanced polymorphism; occurs when the frequency of a phenotype in a population determines the fitness of that trait __L_ mating of genetically similar or genetically close individuals __C_ gradual change in a species phenotype and genotype through a series of geographically separate populations of the same species _D_ natural selection selects against phenotypic extremes and favors intermediate phenotypes __E_ natural selection selects against the intermediates and favors the phenotypic extremes __J_ difference in genotype and phenotype frequencies in a population as a result of an environmental gradient (altitude for example) _A_ a type of genetic polymorphism in which two or more alleles persist in a population as a result of natural selection

A. Balanced Polymorphism B. Bottleneck Effect C. Cline D. Directional Selection E. Disruptive Selection F. Founder Effect G. Frequency Dependent Selection H. Genetic Drift I. Genetic Polymorphism J. Geographic variation (cline) K. Heterozygote Advantage L. Inbreeding M. Stabilizing Selection

1. Define, compare and contrast, and give examples of microevolution including, nonrandom mating (inbreeding, assortative mating), mutation, genetic drift (bottleneck effect and founder effect), and gene flow Microevolution is the generation-to-generation changes within the population. Nonrandom mating is when mates seek others of similar size and textures. Within nonrandom mating, inbreeding and assertive mating occurs. With inbreeding the individuals are more closely related than if chosen randomly from the general population. Mutation can be spontaneous and produces genetic variation. Genetic drift will decrease the genetic variation within a population. An example of this is the bottleneck effect that decrease the population rapidly and randomly, and the founder effect when a few individuals found a colony. Gene flow generally increases variation within population and describes the migration of breeding individuals between two populations. 2. Define, compare and contrast, and give examples of natural selection and the impact on allele frequencies through mechanisms such as stabilizing selection, directional selection, and disruptive selection (drawing helpful!) Natural selection is when individuals with greater fitness are able to adapt to their environment. This causes changes in normal phenotypic distributions and will favor the alleals that are of greater fitness. Stabilizing selection is when the selective pressures do not favor the phenotypes on the ends of the curve. Directional selection will favor one side of the curve. Disruptive selection will favor colaltions at both ends of the distribution and is unfavorable to the middle of the curve.

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3. Define, compare and contrast, and give examples of genetic polymorphism, balanced polymorphism, heterozygote advantage, frequency dependent selection, and geographic variation (cline) Genetic polymorphism is genetic variation between members of the population, with an example being blood type. Balanced polymorphism is when two or more alleles persist in a population, with an example of this being the heterozygote advantage with malarial. Frequency-dependent selection is when a phenotype has greater selective phenotype value when rare rather than when common with an example of this being cichlids with different angled mouths. Geographic variation is the genetic variation among different groups within the same species with an example being the yarrow plant.

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Chapter 20 Objectives: Speciation and Macroevolution _A_ evolution of several species from one or a few ancestral species; occurs in relatively short time frame _H_ an area of overlap between closely related species or subspecies in which interbreeding occurs _K_ retention of juvenile features in the adult body form _O_ evolution proceeds with period of little or no change and then rapid changes occur over a relatively brief period of time C__ formation of two new species following the physical separation of individuals of a single population _N_ something that occurs after fertilization (formation of a zygote) that prevents a hybrid from living long enough to form a new species _F_ gametes of interspecies hybrid are not normal and able to produce a zygote _G_ the hybrid is unable to reproduce successfully; F1 and F2 generations may be produced _J_ small-scale changes that occur within a species as a result of changes in the allele or genotype frequencies _B_ growth of different body parts at different rates _L_ a characteristic that functioned in one way originally but later changed in a way that was adaptive to the structure having a different role _I_ large-scale changes over long time periods resulting in phenotypic changes that warrant placement of the organism into a new taxonomic group at or above the species level _P_ formation of two new species within the geographic region of the parent population; no physical barrier is present but reproductive isolating mechanisms are _M_ something that prevents fertilization from occurring (prevents formation of a zygote); prevents hybrid formation _D_ evolution occurs as a result of slow steady changes over time _E_ egg and sperm of two different species are genetically incapable of producing a viable zygote and embryo

A. Adaptive Radiation B. Allometric Growth C. Allopatric Speciation D. Gradualism E. Hybrid Inviability F. Hybrid Sterility G. Hybrid Breakdown H. Hybrid Zone I. Macroevolution J. Microevolution K. Paedomorphosis L. Preadaptation M. Prezygotic Barrier N. Postzygotic Barrier O. Punctuated Equilibrium P. Sympatric Speciation

1. Compare and contrast and give examples of prezygotic and postzygotic isolating mechanisms and barriers for reproductive isolation (e.g. temporal, habitat, behavioral, mechanical, and gametic isolation; hybrid isolating mechanisms) Prezygotic barriers are those that happen before zygote formation, whereas postzygotic barriers are those that occur following zygote formation. An example of a prezygotic barrier is mechanical isolation, where there are structural differences in reproductive organs that prevent mating. An example of a postzygotic barrier is hybrid inviability, where the embryo of interspecific hybrid spontaneously aborts.

2. Define, describe and discuss macroevolution in the context of novel features, including preadaptations, allometric growth, and paedomorphosis Preadaptations is when new structures suddenly appear. Allometric growth is when growth rate of a particular body part changes over time. Paedomorphosis is the retention of juvenile characteristics as an adult.

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3. Name, define, compare and contrast the three types of hybrid zones (drawing helpful!) There are three hybrid zones- reinforcement zone, fusion zone and stability zone. Reinforcement zone is when overtime the hybrid is less fit than either the parents and the hybrid is no longer produced. Fusion zone is when over time differences in parental species weaken and hybrid numbers increase. Stability zone is where over time hybrids stabilize as a new species.

4. Define and describe the biological species concept of speciation and the associated problems A species is reproductively isolated and fertile offspring are produced. This only included sexual reproductions, whereas sometimes successful inbreeding can occur.

5. Define, compare and contrast and give examples of allopatric and sympatric speciation Allopatric speciation occurs when there is a physical separation of breeding members in the population. This can result in reproductive isolation of the two groups, potentially allowing a new species to evolve. Sympatric speciation is when breeding members of the population become reproductively isolates. This can occur in two ways: change in ploidy or change in ecology. This can cause two new species to evolve and maintain.

6. Name, define, compare and contrast the types of rate and pattern of speciation Punctuated equilibrium is long periods of stats followed by a short period of rapid speciation. This causes the species to have no intermediates and a rapid formation of new ones. Gradualism is the continual evolution of a new species over a long period of time. This makes it so there are intermediate changes in between.

7. Define, describe and discuss the macroevolutionary significance of adaptive radiation and extinction Macroevolution is the change in basic features from an existing organisms. A large-scale phenotypic change can result in a new taxon name. An example is jointed limbs in the evolution of arthropods or the appearance of feathers in birds.

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Chapter 22 Objectives: The Evolution of Primates _C_ one that can be used like an arm or leg for grasping and holding on _B_ swinging from limb to limb in trees for example _D_ moving on all four limbs _E_ seeing an object at the same time with both eyes in the same plane with a slightly different perspective gives depth perception, width, height, etc. _A_ living in the trees

A. B. C. D.

Arboreal Brachiation Prehensile Tail Quadrupedal Movement E. Stereoscopic Vision

1. Reconstruct the cladogram for primate evolution; name and give examples of the three suborders of primates; distinguish among anthropoids, hominoids, and hominins. The three suborders are prosimii, tarsiiformes and anthropoidea. Prosimii have lemurs and lorises in the suborder. Tarsiiformers include tarsiers. Anthropoidea includes monkeys, apes, and humans. Anthopoids can be set apart between new and old world monekys. Homonoids arose from old world monkey lineage.

2. List and describe differences between Old World and New World monkeys Old world monkeys come from Asia and Africa and have non-grasping tails. This includes baboons, Mandrills, Macaques and Colobus. New world monkeys use their tails to balance in trees and as another hand.

3. Describe skeletal and skull differences between apes and hominins Apes have a C shaped spine causing their arms the be longer and hominis have an S shaped spine causing the arms to be shorter than the legs. The human brain is larger and the skull is flatter in the front. The apes have rectangular shaped teeth and have a supraorbital ridge.

4. Describe locomotion in hominoids Brachiation is the swinging from limb to limb and are tree dwellers (gibbons and orangutans). Knuckle walking (chimpanzees and gorillas) use their arms to assist in quadrupedal walking. Hominini walk upright (humans). 5. Describe adaptations in primates as they moved from an arboreal existence

6. Name the five most recent species of hominids

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