Systems Thinking, Abiogenesis, Origin of Life
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Chemistry Grade Level 10 Units 1-15
COPPELL ISD SUBJECT YEAR AT A GLANCE GRADE HEMISTRY UNITS C LEVEL 1-15 10 Program Transfer Goals ● Ask questions, recognize and define problems, and propose solutions. ● Safely and ethically collect, analyze, and evaluate appropriate data. ● Utilize, create, and analyze models to understand the world. ● Make valid claims and informed decisions based on scientific evidence. ● Effectively communicate scientific reasoning to a target audience. PACING 1st 9 Weeks 2nd 9 Weeks 3rd 9 Weeks 4th 9 Weeks Unit 1 Unit 2 Unit 3 Unit 4 Unit 5 Unit 6 Unit Unit Unit Unit Unit Unit Unit Unit Unit 7 8 9 10 11 12 13 14 15 1.5 wks 2 wks 1.5 wks 2 wks 3 wks 5.5 wks 1.5 2 2.5 2 wks 2 2 2 wks 1.5 1.5 wks wks wks wks wks wks wks Assurances for a Guaranteed and Viable Curriculum Adherence to this scope and sequence affords every member of the learning community clarity on the knowledge and skills on which each learner should demonstrate proficiency. In order to deliver a guaranteed and viable curriculum, our team commits to and ensures the following understandings: Shared Accountability: Responding -
Modelling Panspermia in the TRAPPIST-1 System
October 13, 2017 Modelling panspermia in the TRAPPIST-1 system James A. Blake1,2*, David J. Armstrong1,2, Dimitri Veras1,2 Abstract The recent ground-breaking discovery of seven temperate planets within the TRAPPIST-1 system has been hailed as a milestone in the development of exoplanetary science. Centred on an ultra-cool dwarf star, the planets all orbit within a sixth of the distance from Mercury to the Sun. This remarkably compact nature makes the system an ideal testbed for the modelling of rapid lithopanspermia, the idea that micro-organisms can be distributed throughout the Universe via fragments of rock ejected during a meteoric impact event. We perform N-body simulations to investigate the timescale and success-rate of lithopanspermia within TRAPPIST-1. In each simulation, test particles are ejected from one of the three planets thought to lie within the so-called ‘habitable zone’ of the star into a range of allowed orbits, constrained by the ejection velocity and coplanarity of the case in question. The irradiance received by the test particles is tracked throughout the simulation, allowing the overall radiant exposure to be calculated for each one at the close of its journey. A simultaneous in-depth review of space microbiological literature has enabled inferences to be made regarding the potential survivability of lithopanspermia in compact exoplanetary systems. 1Department of Physics, University of Warwick, Coventry, CV4 7AL 2Centre for Exoplanets and Habitability, University of Warwick, Coventry, CV4 7AL *Corresponding author: [email protected] Contents Universe, and can propagate from one location to another. This interpretation owes itself predominantly to the works of William 1 Introduction1 Thompson (Lord Kelvin) and Hermann von Helmholtz in the 1.1 Mechanisms for panspermia...............2 latter half of the 19th Century. -
Oligomeric A2 + B3 Approach to Branched Poly(Arylene Ether Sulfone)
“One-Pot” Oligomeric A 2 + B 3 Approach to Branched Poly(arylene ether sulfone)s: Reactivity Ratio Controlled Polycondensation A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science By ANDREA M. ELSEN B.S., Wright State University, 2007 2009 Wright State University WRIGHT STATE UNIVERSITY SCHOOL OF GRADUATE STUDIES June 19, 200 9 I HEREBY RECOMMEND THAT THE THESIS PREPARED UNDER MY SUPERVISION BY Andrea M. Elsen ENTITLED “One-Pot” Oligomeric A2 + B3 Approach to Branched Poly(arylene ether sulfone)s: Reactivity Ratio Controlled Polycondenstation BE ACCEPTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Master of Science . _________________________ Eric Fossum, Ph.D. Thesis Director _________________________ Kenneth Turnbull, Ph.D. Department Chair Committee on Final Examination ____________________________ Eric Fossum, Ph.D. ____________________________ Kenneth Turnbull, Ph.D. ____________________________ William A. Feld, Ph.D. ____________________________ Joseph F. Thomas, Jr., Ph.D. Dean, School of Graduate Studies Abstract Elsen, Andrea M. M.S., Department of Chemistry, Wright State University, 2009. “One-Pot” Oligomeric A 2 + B 3 Approach to Branched Poly(arylene ether sulfone)s: Reactivity Ratio Controlled Polycondensation The synthesis of fully soluble branched poly(arylene ether)s via an oligomeric A 2 + B 3 system, in which the A 2 oligomers are generated in situ, is presented. This approach takes advantage of the significantly higher reactivity toward nucleophilic aromatic substitution reactions, NAS, of B 2, 4-Fluorophenyl sulfone, relative to B 3, tris (4-Fluorophenyl) phosphine oxide. The A 2 oligomers were synthesized by reaction of Bisphenol-A and B 2, in the presence of the B 3 unit, at temperatures between 100 and 160 °C, followed by an increase in the reaction temperature to 180 °C at which point the branching unit was incorporated. -
Prebiological Evolution and the Metabolic Origins of Life
Prebiological Evolution and the Andrew J. Pratt* Metabolic Origins of Life University of Canterbury Keywords Abiogenesis, origin of life, metabolism, hydrothermal, iron Abstract The chemoton model of cells posits three subsystems: metabolism, compartmentalization, and information. A specific model for the prebiological evolution of a reproducing system with rudimentary versions of these three interdependent subsystems is presented. This is based on the initial emergence and reproduction of autocatalytic networks in hydrothermal microcompartments containing iron sulfide. The driving force for life was catalysis of the dissipation of the intrinsic redox gradient of the planet. The codependence of life on iron and phosphate provides chemical constraints on the ordering of prebiological evolution. The initial protometabolism was based on positive feedback loops associated with in situ carbon fixation in which the initial protometabolites modified the catalytic capacity and mobility of metal-based catalysts, especially iron-sulfur centers. A number of selection mechanisms, including catalytic efficiency and specificity, hydrolytic stability, and selective solubilization, are proposed as key determinants for autocatalytic reproduction exploited in protometabolic evolution. This evolutionary process led from autocatalytic networks within preexisting compartments to discrete, reproducing, mobile vesicular protocells with the capacity to use soluble sugar phosphates and hence the opportunity to develop nucleic acids. Fidelity of information transfer in the reproduction of these increasingly complex autocatalytic networks is a key selection pressure in prebiological evolution that eventually leads to the selection of nucleic acids as a digital information subsystem and hence the emergence of fully functional chemotons capable of Darwinian evolution. 1 Introduction: Chemoton Subsystems and Evolutionary Pathways Living cells are autocatalytic entities that harness redox energy via the selective catalysis of biochemical transformations. -
Quasispecies Theory in Virology
JOURNAL OF VIROLOGY, Jan. 2002, p. 463–465 Vol. 76, No. 1 0022-538X/02/$04.00ϩ0 DOI: 10.1128/JVI.76.1.463–465.2002 Copyright © 2002, American Society for Microbiology. All Rights Reserved. Quasispecies Theory in Virology Holmes and Moya claim that quasispecies is an unnecessary ular sort. Darwinian principles in connection with quasispecies and misleading description of RNA virus evolution, that virol- have been explicitly invoked by theoreticians and experimen- ogists refer to quasispecies inappropriately, and that there is talists alike (11, 13, 16, 35). little evidence of quasispecies in RNA virus evolution. They What is the evidence of quasispecies dynamics in RNA virus wish to look for other ideas in evolutionary biology and to set populations, and why is quasispecies theory exerting an influ- down an agenda for future research. I argue here that real virus ence in virology? The initial experiment with phage Q which quasispecies often differ from the theoretical quasispecies as provided the first experimental support for a quasispecies dy- initially formulated and that this difference does not invalidate namics in an RNA virus (14, 17) has now been carried out with quasispecies as a suitable theoretical framework to understand biological and molecular clones of representatives of the major viruses at the population level. groups of human, animal, and plant RNA viruses, including In the initial theoretical formulation to describe error-prone immunodeficiency viruses and hepatitis C virus, both in cell replication of simple RNA (or RNA-like) molecules, quasispe- culture and in vivo (11). Support for quasispecies has also cies were defined as stationary (equilibrium) mutant distribu- come from studies on replication of RNA molecules in vitro tions of infinite size, centered around one or several master (4). -
Dynamics of a Discrete Hypercycle
Treball final de grau GRAU DE MATEMÀTIQUES Facultat de Matemàtiques i Informàtica Universitat de Barcelona Dynamics of a Discrete Hypercycle Autor: Júlia Perona García Directors: Dr. Ernest Fontich, Dr. Josep Sardanyés Realitzat a: Departament de Matemàtiques i Informàtica Barcelona, June 27, 2018 Abstract The concept of the Hypercycle was introduced in 1977 by Manfred Eigen and Peter Schuster within the framework of origins of life and prebiotic evolution. Hypercycle are catalytic sets of macromolecules, where each replicator catalyzes the replication of the next species of the set. This system was proposed as a possible solution to the information crisis in prebiotic evolution. Hypercycles are cooperative systems that allow replicators to increase their information content beyond the error threshold. This project studies the dynamics of a discrete-time model of the hypercycle consider- ing heterocatalytic interactions. To date, hypercycles’ dynamics has been mainly studied using continuous-time dynamical systems. We follow the Hofbauer’s discrete model [13]. First, we introduce some important and necessary mathematical notions. Then, we also review the biological concept of the hypercycle and some criticisms that it has received. We present a complete proof of the fact that the hypercycle is a cooperative system. Also, we present an analytic study of the fixed point in any dimension and its stability. In particular, in dimension three we prove that fixed point is globally asymptotically stable. In dimension four we have obtained a stable invariant curve for all values of the discreteness parameter. 2010 Mathematics Subject Classification. 37C05, 37N25 Acknowledgements I would like to thank my directors, Ernest and Josep, to support me throughout this project. -
4.2 Ionic Bonds Vocabulary: Ion – Polyatomic Ion – Ionic Bond – Ionic Compound – Chemical Formula – Subscript –
4.2 Ionic Bonds Vocabulary: Ion – Polyatomic ion – Ionic bond – Ionic compound – Chemical formula – Subscript – Crystal - An ion is an atom or group of atoms that has an electric charge. When a neutral atom loses a valence electron, it loses a negative charge. It becomes a positive ion. When a neutral atom gains an electron, it gains a negative charge and becomes a negative ion. Common Ions: Name Charge Symbol/Formula Lithium 1+ Li+ Sodium 1+ Na+ Potassium 1+ K+ Ammonium 1+ NH₄+ Calcium 2+ Ca²+ Magnesium 2+ Mg²+ Aluminum 3+ Al³+ Fluoride 1- F- Chloride 1- Cl- Iodide 1- I- Bicarbonate 1- HCO₃- Nitrate 1- NO₃- Oxide 2- O²- Sulfide 2- S²- Carbonate 2- CO₃²- Sulfate 2- SO₄²- Notice that some ions are made of several atoms. Ammonium is made of 1 nitrogen atom and 4 hydrogen atoms. Ions that are made of more than 1 atom are called polyatomic ions. Ionic bonds: When atoms that easily lose electrons react with atoms that easily gain electrons, valence electrons are transferred from one type to another. The transfer gives each type of atom a more stable arrangement of electrons. 1. Sodium has 1 valence electron. Chlorine has 7 valence electrons. 2. The valence electron of sodium is transferred to the chlorine atom. Both atoms become ions. Sodium atom becomes a positive ion (Na+) and chlorine becomes a negative ion (Cl-). 3. Oppositely charged particles attract, so the ions attract. An ionic bond is the attraction between 2 oppositely charged ions. The resulting compound is called an ionic compound. In an ionic compound, the total overall charge is zero because the total positive charges are equal to the total negative charges. -
The Molecular Underpinnings of Genetic Phenomena
Heredity (2008) 100, 6–12 & 2008 Nature Publishing Group All rights reserved 0018-067X/08 $30.00 www.nature.com/hdy SHORT REVIEW The molecular underpinnings of genetic phenomena N Lehman Department of Chemistry, Portland State University, Portland, OR, USA Epiphenomena are those processes that ostensibly have no whole organisms and populations may have their ultimate precedent at lower levels of scientific organization. In this evolutionary roots in the chemical repertoire of catalytic review, it is argued that many genetic processes, including RNAs. Some of these phenomena will eventually prove to be ploidy, dominance, heritability, pleiotropy, epistasis, muta- not only analogous but homologous to ribozyme activities. tional load and recombination, all are at least analogous to Heredity (2008) 100, 6–12; doi:10.1038/sj.hdy.6801053; biochemical events that were requisite features of the RNA published online 29 August 2007 world. Most, if not all, of these features of contemporary Keywords: RNA; ploidy; pleiotropy; epistasis; heritability; recombination Introduction Below are discussed seven well-known genetic pro- cesses for which a clear molecular basis can be The history of life, if traced with perfect detail, would postulated. By ‘molecular basis’ it is meant that a reveal a long and gradual expansion of networks of chemical property of biopolymers, usually RNA, can be chemical reactions. If viewed in less detail, a series of identified as a direct forbearer of the higher-order plateaus would be seen, each representing a discrete property observed in whole organisms. Again, an advancement in complexity (Fontana and Schuster, 1998; important aspect of this is the idea that many of these Hazen et al., 2007). -
Analysis of Multipolar Linear Paul Traps for Ion–Atom Ultracold Collision Experiments
atoms Article Analysis of Multipolar Linear Paul Traps for Ion–Atom Ultracold Collision Experiments M. Niranjan *, Anand Prakash and S. A. Rangwala * Raman Research Institute, C. V. Raman Avenue, Sadashivanagar, Bangalore 560080, India; [email protected] * Correspondence: [email protected] (M.N.); [email protected] (S.A.R.) Abstract: We evaluate the performance of multipole, linear Paul traps for the purpose of studying cold ion–atom collisions. A combination of numerical simulations and analysis based on the virial theorem is used to draw conclusions on the differences that result, by considering the trapping details of several multipole trap types. Starting with an analysis of how a low energy collision takes place between a fully compensated, ultracold trapped ion and an stationary atom, we show that a higher order multipole trap is, in principle, advantageous in terms of collisional heating. The virial analysis of multipole traps then follows, along with the computation of trapped ion trajectories in the quadrupole, hexapole, octopole and do-decapole radio frequency traps. A detailed analysis of the motion of trapped ions as a function of the amplitude, phase and stability of the ion’s motion is used to evaluate the experimental prospects for such traps. The present analysis has the virtue of providing definitive answers for the merits of the various configurations, using first principles. Keywords: ion trapping; ion–atom collisions; linear multipole traps; virial theorem Citation: Niranjan, M.; Prakash, A.; Rangwala, S.A. Analysis of Multipolar Linear Paul Traps for 1. Introduction Ion–Atom Ultracold Collision Linear multipole Paul trap configurations are emerging as a natural choice for a wide Experiments. -
Chemical Evolution Theory of Life's Origins the Lattimer, AST 248, Lecture 13 – P.2/20 Organics
Chemical Evolution Theory of Life's Origins 1. the synthesis and accumulation of small organic molecules, or monomers, such as amino acids and nucleotides. • Production of glycine (an amino acid) energy 3HCN+2H2O −→ C2H5O2N+CN2H2. • Production of adenine (a base): 5 HCN → C5H5N5, • Production of ribose (a sugar): 5H2CO → C5H10O5. 2. the joining of these monomers into polymers, including proteins and nucleic acids. Bernal showed that clay-like materials could serve as sites for polymerization. 3. the concentration of these molecules into droplets, called protobionts, that had chemical characteristics different from their surroundings. This relies heavily on the formation of a semi-permeable membrane, one that allows only certain materials to flow one way or the other through it. Droplet formation requires a liquid with a large surface tension, such as water. Membrane formation naturally occurs if phospholipids are present. 4. The origin of heredity, or a means of relatively error-free reproduction. It is widely, but not universally, believed that RNA-like molecules were the first self-replicators — the RNA world hypothesis. They may have been preceded by inorganic self-replicators. Lattimer, AST 248, Lecture 13 – p.1/20 Acquisition of Organic Material and Water • In the standard model of the formatio of the solar system, volatile materials are concentrated in the outer solar system. Although there is as much carbon as nearly all other heavy elements combined in the Sun and the bulk of the solar nebula, the high temperatures in the inner solar system have lead to fractional amounts of C of 10−3 of the average. -
Nomination Background: Dihydroxyacetone (CASRN: 96-26-4)
SUMMARY OF DATA FOR CHEMICAL SELECTION Dihydroxyacetone 96-26-4 BASIS OF NOMINATION TO THE CSWG As consumers have become more mindful of the hazards ofa "healthy tan," more individuals have turned to sunless tanning. Sunless tanning products represent about 10% of the $400 million market for suntan preparations, and these products are the fastest growing segment of the suntanning preparation market. All sunless tanners contain dihydroxyacetone. Information on the toxicity of dihydroxyacetone appears contradictory. A mutagen that induces DNA strand breaks, dihydroxyacetone is also an intermediate in carbohydrate metabolism in higher plants and animals. Such contradictions are not unprecedented, and it has been suggested that autooxidation of cx-hydroxycarbonyl compounds including reducing sugars may play a role in diseases associated with age and diabetes (Morita, 1991 ). When dihydroxyacetone was applied to the skin of mice, no carcinogenic effect was observed. It is unclear whether this negative response was caused by a failure ofthe compound to penetrate the skin. If so, extrapolating the dermal results to other routes of exposure would not be appropriate. NCI is nominating dihydroxyacetone to the NTP for dermal penetration studies in rats and mice to determine whether dihydroxyacetone can penetrate the skin. This information will clarify whether additional testing of dihydroxyacetone is warranted. Dihydroxyacetone 96-26-4 CHEMICAL IDENTIFICATION CAS Registry Number: 96-26-4 Chemical Abstracts Service Name: 1,3-Dihydroxy-2-propanone (9CI; 8CI) Synonyms and Tradenames: 1,3-Dihydroxydimethyl ketone; Chromelin; CTF A 00816; Dihyxal; Otan; Oxantin; Oxatone; Soleal; Triulose; Viticolor Structural Class: Ketone, ketotriose compound Structure. Molecular Formula. and Molecular Weight: 0 II /c"-. -
Specifications Guide Americas Petrochemicals Latest Update: July 2020
Specifications Guide Americas Petrochemicals Latest update: July 2020 Definitions of the trading locations for which Platts publishes daily indexes or assessments 2 Olefins 3 US aromatics 6 Latin American aromatics 8 US polymers 10 Latin American polymers 13 US intermediates 16 US hydrocarbon solvents 17 US chlor alkali 18 US oxygenated solvents 19 Liquid and gas chemical freight 21 Global petrochemical indices 22 Revision history 23 www.spglobal.com/platts Specifications Guide Americas Petrochemicals: July 2020 DEFINITIONS OF THE TRADING LOCATIONS FOR WHICH PLATTS PUBLISHES DAILY INDEXES OR ASSESSMENTS The following specifications guide contains the primary specifications for S&P Global Platts petrochemical assessments in the Americas. All the assessments listed here employ Platts Assessments Methodology, as published at https://www.spglobal.com/platts/plattscontent/_assets/_files/en/our-methodology/methodology-specifications/platts-assessments-methodology-guide.pdf. These guides are designed to give Platts subscribers as much information as possible about a wide range of methodology and specification questions. This guide is current at the time of publication. Platts may issue further updates and enhancements to this methodology and will announce these to subscribers through its usual publications of record. Such updates will be included in the next version of this guide. Platts editorial staff and managers are available to provide guidance when assessment issues require clarification. OLEFINS Assessment CURRENCY CODE Mavg Wavg TYPE