A. Incorrect! Darwin could not draw complete conclusions because of the lack of fossils.

Transcription

1 High School Biology - Problem Drill 15: Evolutionary History Question No. 1 of Which of the following statements is incorrect? Question #01 (A) Darwin was unable to come to a firm conclusion because of lack of fossil evidence. (B) Earth was formed about 3.55 billion years ago. (C) The basic structure of the earth was tectonic plates, mantle and core. (D) Life existed about 3.55 billion years ago. (E) All of these statements are correct. Darwin could not draw complete conclusions because of the lack of fossils. B. Correct! The earth was formed 1 billion years before life existed. The basic structure of the earth was tectonic plates, mantle and core. The first life existed about 3.55 billion years ago. One of these statements is incorrect, so this cannot be the right choice. Darwin discussed Origin of Species. He was unsure about Origin of Life because of paucity of fossil evidence. The fossils were undetected for the first ~ billion years of evolutionary history. The evidence of earliest life via fossil records may not be possible because the ability of fossils to record history was limited. This may be due to the fact that organisms with exo / endoskeletons favor fossilization and those without are less likely to be fossilized and found. Organisms with cell membranes, but without cell walls (for example, mycoplasma today), may not fossilize. Earth was formed about 4.55 billion years ago. Advanced forms of life on earth existed at least 3.55 billion years ago. Imprints of bacteria have been found in rock from that long ago! Basic structure of earth: Continents float on crust or tectonic plates. Mantle is the semi- solid layer between the crust and the core. The core is made up of heavy metals. The correct answer is (B).

2 Question No. 2 of What did Urey and Miller set out to prove? Question #02 (A) That the world was flat. (B) That organic compounds could be synthesized under the natural conditions of early earth. (C) That prokaryotes were the first forms of life. (D) That plants produce energy from sulfur. (E) That organisms need oxygen for survival. They did not show that the world was flat. B. Correct! They set out to show how organic compounds developed by simulating how the earth was in the beginning of life. They did not show that prokaryotes were the first life forms. They did not show that plants use sulfur to make energy. They did not show the need for oxygen. The early earth atmosphere was thought to be a reducing, as opposed to oxidizing, atmosphere of today. In Miller s experiment, he created a model system of early earth using only inorganic molecules. Over time, organic molecules (nucleic acids, amino acids) developed. With pre-biotic conditions set, proto-life may occur, according to the following sequence of events: Proto-life----Organic compounds--- polymers of repeating units---lipids & others can and do organize into spheres based on inherent properties----lipid spheres can encapsulate organic molecules----encapsulated organic molecules, such as RNA, that can self-replicate, are autocatalytic, can act as rudimentary templates for protein synthesis---these can compete for scarce resources such as RNA monomers---- this leads to competition and natural selection of fittest of the RNA molecule---leading to reproduction of that RNA molecule---lipids can spontaneously form bilayers (like a cell s membrane). These lipid bilayers (liposomes) can encapsulate organic polymers like RNA, sugars and proteins and fats. The correct answer is (B).

3 Question No. 3 of Endosymbiotic hypothesis states that eukaryotes are derived from? Question #03 (A) RNA (B) Nitrogen (C) Fats (D) Carbohydrates (E) Larger prokaryotes swallowing a smaller prokaryote. Eukaryotes did not develop from just RNA. B. Incorrect! Eukaryotes are made of more than just nitrogen. Eukaryotes are made of more than just fats. Eukaryotes are made of more than just carbohydrates. E. Correct! The hypothesis suggests that a large prokaryotic cell engulfed a small prokaryotic cell. Endosymbiotic hypothesis attempts to account for the major evolutionary leap between prokaryotes and protests, which are the first eukaryotes. The hypothesis proposes that a larger prokaryote ingested a smaller prokaryote. Instead of killing the smaller cell, it lived in symbiosis inside of the large cell. This was the precursor to organelles, such as mitochondria and chloroplasts. Much evidence comparing similarities of mitochondria and chloroplasts to prokaryotes supports this idea. The correct answer is (E).

4 Question No. 4 of According to the theory of paedogenesis, what happens to larvae? Question #04 (A) They become extinct. (B) They mature faster than usual, reproductively. (C) They change into stationary life forms. (D) They never develop into an adult. (E) None of the above The larvae do not become extinct. B. Correct! The larvae do reach reproductive maturity before they reach adulthood. The larvae do not always develop into stationary adults. The larvae do develop into adults. The correct answer is listed among the choices. In paedogenesis, the larvae reach reproductive maturity before reaching adulthood maintenance of larval life cycle and morphology major change in body plan. It is belived that paedogenesis of early larval chordates maintenance of motile organism with chordate features subsequent selection pressures favored. These selective pressures acting on paedogenic larval urochordates modifications of chordate traits that did not exist in mature adult. The correct answer is (B).

5 Question No. 5 of What is the proposed order of events in the lineage leading to the modern human? Question #05 (A) Walk erect 3x expanded brain mass walk upright. (B) 3x expanded brain mass walk erect walk upright. (C) Walk erect walk upright 3x expanded brain mass. (D) Walk upright walk erect3x expanded brain mass. (E) None of the above This is not the correct sequence of events. Walking upright happened before 3x expanded brain mass. B. Incorrect This is not the correct sequence of events. 3x expanded brain mass is one of the last events. C. Correct! This is the correct sequence of events for human evolution. This is not the correct sequence of events. Humans needed to walk erect before upright. This answer is listed here, so it cannot be none of the above. This shows the evolutionary chronology of humans. Ramapithicus----- Australopithecus afarensis (Walked erect)---- Australopithecus africanus (hominid)---- Homo habilis : handy man (Used simple stone tools)---- Homo erectus: upright man 2x larger brain then earliest predecessor--- Homo sapiens (Modern Humans): Brain size 3x larger then Australopithecus, oldest fossil ~ 90,000 years old---neanderthals: Brain size larger then modern humans, but extinct. The correct answer is (C).

6 Question No. 6 of Which of the following statements is correct? Question #06 (A) Miller s experiment attempted to show that protists developed as a process of spontaneous animation. (B) Liposomes are encapsulated molecules of RNA. (C) Miller s experiment created life from prokaryotic cells. (D) RNA can form bilayers spontaneously. (E) None of these statements is correct. The experiment set out to show that organic molecules developed from inorganic chemicals. B. Incorrect! Liposomes are lipid bilayers that can encapsulate RNA. The experiment set out to show that organic molecules developed from inorganic chemicals. Lipids can spontaneously form bilayers. E. Correct! None of the following statements is correct, so this represents the right answer. The early earth atmosphere was thought of as a reducing, as opposed to oxidizing, atmosphere of today. In Miller s experiment, he created a model system of early earth using only inorganic molecules. Over time, organic molecules (nucleic acids, amino acids) developed. With pre-biotic conditions set, proto-life may occur, according to the following sequence of events: Proto-life----Organic compounds--- polymers of repeating units---lipids & others can and do organize into spheres based on inherent properties----lipid spheres can encapsulate organic molecules----encapsulated organic molecules, such as RNA, that can self-replicate, are autocatalytic, can act as rudimentary templates for protein synthesis---these can compete for scarce resources, such as RNA monomers---- this leads to competition and natural selection of fittest of the RNA molecule---leading to reproduction of that RNA molecule---lipids can spontaneously form bilayers (like a cell s membrane). These lipid bilayers (liposomes) can encapsulate organic polymers like RNA, sugars and proteins and fats. The correct answer is (E).

7 Question No. 7 of Which of the following is the correct proposal for organismal evolution? Question #07 (A) First life forms--archaebacteria protists eubacteria. (B) First life forms archaebacteia eubacteria protists. (C) First life forms eubacteria protists archaebacteria. (D) First life forms protists archaebacteria eubacteria. (E) First life forms eubacteria archaebacteria protists. This is not the correct sequence because protists developed from bacteria. B. Correct! This is the correct sequence. This is not the correct sequence because protists developed from bacteria. This is not the correct sequence because protists developed from bacteria. This is not the correct sequence because eubacteria developed from archaebacteria. The following shows the chronology of the development of living things. 1.) Organic compounds polymers of repeating units 2.) Lipids & others can and do organize into spheres based on inherent properties. 3.) Lipid spheres can encapsulate organic molecules 4.) Encapsulated organic molecules, such as RNA, can self-replicate, are autocatalytic, and can act as rudimentary templates for protein synthesis. Compete for scarce resources such as RNA monomers Competition natural selection of fittest of the RNA molecule reproduction of that RNA molecule. RNA molecules developed into primitive bacteria, called archaebacteria. Then, archeabacteria were the first bacteria because they are equipped to live in extreme habitats. Next, came the eubacteria, and then the protists developed. The correct answer is (B).

8 Question No. 8 of Which of the following is/are examples of protists? Question #08 (A) E.coli (B) Amoeba (C) Alga (D) Mushroom (E) B & C E.coli is a bacterium and is not an example of a protist. B. Incorrect! An amoeba is an example of a protist. It is not the only example listed here. An alga is an example of a protist. It is not the only example listed here. Mushroom is not an example of a protist. It is a fungus. E. Correct! Both amoeba and algae are examples of protists. Protists are the first eukaryotes. Protists are diverse and made up of those eukaryotes that cannot be classed into any of the other kingdoms as fungi, animals, or plants. Protists have been traditionally divided into groups based on their morphology, ecology, and similarities to higher kingdoms. Therefore, they have been thought of as: plant-like, fungus-like or animal-like. This has been replaced by phylogenetic classification but is useful for describing protists. Examples of protists include: amoebas, algae and slime molds. The correct answer is (E).

9 Question No. 9 of Which of the following statements is incorrect? Question #09 (A) Plants developed from green algae. (B) A key adaption for plants was the development of cuticles. (C) Animal developed from flagellated protists. (D) The first animal fossils appeared about 300 million years ago. (E) All statements are correct. Plants developed from photosynthetic protests, called green algae. B. Incorrect! One of the adaptations of plants was the development of the cuticle to prevent desiccation. Animals did develop from flagellated protists. D. Correct! The first animal fossils appeared about 575 million years ago. All of these statements are not correct, so this cannot be the answer. Early plants were unicellular or filamentous. It is estimated the first plants evolved around 3000 million years ago. All plants are multicellular eukaryotes with the capacity for photosynthesis that developed for alga protists. The newly developed plants had the following adaptations: Cuticles to prevent drying System of specialized cells Vascular conduits, which provided more efficient water transport and allowed new niches further away from water sources Animals are thought to have evolved from flagellated eukaryotes. The first animal fossils appeared around 575 million years ago and are called Ediacaran. They may or may not belong to the animal kingdom. Most known animal phyla appear almost simultaneously about 542 million years ago during the Cabrian explosion. The correct answer is (D).

10 Question No. 10 of Which of the following is/are characteristic(s) of chordates? Question #10 (A) Notochord (B) Nerve cord (C) Pharyngeal slits (D) Post-anal tail (E) All of the above are characteristics of chordates. This is a chordate characteristic, but it is not the only one listed here. B. Incorrect! This is a chordate characteristic, but it is not the only one listed here. This is a chordate characteristic, but it is not the only one listed here. This is a chordate characteristic, but it is not the only one listed here. E. Correct! All of these are characteristics of chordates. Here are the taxonomic relationships, based on comparative anatomy and embryology: Ancestral Protists----Eumetazoa----Bilateria/Radiata (Major change in body plan: Radial vs. Bilateral)------Coelomates (Inner body cavity tube lined completely by mesoderm)------deuterostomes (All members in this group have radial cleavage patterns in embryogenesis) chordates (All members have notochord, nerve cord, pharyngeal slits, and post-anal tail)----vertebrates (All members have back bone/vertebral column). The correct answer is (E).