Prebiological Evolution and the Metabolic Origins 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. -
A Chemical Engineering Perspective on the Origins of Life
Processes 2015, 3, 309-338; doi:10.3390/pr3020309 processesOPEN ACCESS ISSN 2227-9717 www.mdpi.com/journal/processes Article A Chemical Engineering Perspective on the Origins of Life Martha A. Grover *, Christine Y. He, Ming-Chien Hsieh and Sheng-Sheng Yu School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Dr. NW, Atlanta, GA 30032, USA; E-Mails: [email protected] (C.Y.H.); [email protected] (M.-C.H.); [email protected] (S.-S.Y.) * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +1-404-894-2878 or +1-404-894-2866. Academic Editor: Michael Henson Received: 29 January 2015 / Accepted: 19 April 2015 / Published: 5 May 2015 Abstract: Atoms and molecules assemble into materials, with the material structure determining the properties and ultimate function. Human-made materials and systems have achieved great complexity, such as the integrated circuit and the modern airplane. However, they still do not rival the adaptivity and robustness of biological systems. Understanding the reaction and assembly of molecules on the early Earth is a scientific grand challenge, and also can elucidate the design principles underlying biological materials and systems. This research requires understanding of chemical reactions, thermodynamics, fluid mechanics, heat and mass transfer, optimization, and control. Thus, the discipline of chemical engineering can play a central role in advancing the field. In this paper, an overview of research in the origins field is given, with particular emphasis on the origin of biopolymers and the role of chemical engineering phenomena. A case study is presented to highlight the importance of the environment and its coupling to the chemistry. -
Why Can't Cosmology Be More Open?
ISSN: 2641-886X International Journal of Cosmology, Astronomy and Astrophysics Opinion Article Open Access Why can’t Cosmology be more open? Jayant Narlikar* Inter-University Centre for Astronomy and Astrophysics, Ganeshkhind, Post Bag 4, Pune-411007, India Article Info Keywords: Cosmology, Galaxy, Big Bang, Spectrum *Corresponding author: More than two millennia back, Pythagoreans believed that the Earth went round a Jayant Narlikar central fire, with the Sun lying well outside its orbit. When sceptics asked,” Why can’t we Emeritus Professor see the fire?”, theorists had to postulate that there was a ‘counter-Earth’ going around Inter-University Centre for Astronomy and Astrophysics the central fire in an inner orbit that blocked our view of the fire. The sceptics asked Ganeshkhind, Post Bag 4 again: why don’t we see this ‘counter-Earth’? The theorists replied that this happened Pune, India because Greece was facing away from it. In due course this explanation too was also Tel: +91-20-25604100 shot down by people sailing around and looking from other directions. Fax: +91-20-25604698 E-mail: [email protected] I have elaborated this ancient episode because it holds a moral for scientists. When you are on the wrong track, you may have to invoke additional assumptions, like the Received: November 5, 2018 counter-Earth, to prop up your original theory against an observed fact. If there is no Accepted: November 15, 2018 other independent support for these assumptions, the entire structure becomes suspect. Published: January 2, 2019 The scientific approach then requires a critical re-examination of the basic paradigm. -
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). -
Natural Coral As a Biomaterial Revisited
American Journal of www.biomedgrid.com Biomedical Science & Research ISSN: 2642-1747 --------------------------------------------------------------------------------------------------------------------------------- Research Article Copy Right@ LH Yahia Natural Coral as a Biomaterial Revisited LH Yahia1*, G Bayade1 and Y Cirotteau2 1LIAB, Biomedical Engineering Institute, Polytechnique Montreal, Canada 2Neuilly Sur Seine, France *Corresponding author: LH Yahia, LIAB, Biomedical Engineering Institute, Polytechnique Montreal, Canada To Cite This Article: LH Yahia, G Bayade, Y Cirotteau. Natural Coral as a Biomaterial Revisited. Am J Biomed Sci & Res. 2021 - 13(6). AJBSR. MS.ID.001936. DOI: 10.34297/AJBSR.2021.13.001936. Received: July 07, 2021; Published: August 18, 2021 Abstract This paper first describes the state of the art of natural coral. The biocompatibility of different coral species has been reviewed and it has been consistently observed that apart from an initial transient inflammation, the coral shows no signs of intolerance in the short, medium, and long term. Immune rejection of coral implants was not found in any tissue examined. Other studies have shown that coral does not cause uncontrolled calcification of soft tissue and those implants placed under the periosteum are constantly resorbed and replaced by autogenous bone. The available porestudies size. show Thus, that it isthe hypothesized coral is not cytotoxic that a damaged and that bone it allows containing cell growth. both cancellous Thirdly, porosity and cortical and gradient bone can of be porosity better replacedin ceramics by isa graded/gradientexplained based on far from equilibrium thermodynamics. It is known that the bone cross-section from cancellous to cortical bone is non-uniform in porosity and in in vitro, animal, and clinical human studies. -
Measurement of Cp/Cv for Argon, Nitrogen, Carbon Dioxide and an Argon + Nitrogen Mixture
Measurement of Cp/Cv for Argon, Nitrogen, Carbon Dioxide and an Argon + Nitrogen Mixture Stephen Lucas 05/11/10 Measurement of Cp/Cv for Argon, Nitrogen, Carbon Dioxide and an Argon + Nitrogen Mixture Stephen Lucas With laboratory partner: Christopher Richards University College London 5th November 2010 Abstract: The ratio of specific heats, γ, at constant pressure, Cp and constant volume, Cv, have been determined by measuring the oscillation frequency when a ball bearing undergoes simple harmonic motion due to the gravitational and pressure forces acting upon it. The γ value is an important gas property as it relates the microscopic properties of the molecules on a macroscopic scale. In this experiment values of γ were determined for input gases: CO2, Ar, N2, and an Ar + N2 mixture in the ratio 0.51:0.49. These were found to be: 1.1652 ± 0.0003, 1.4353 ± 0.0003, 1.2377 ± 0.0001and 1.3587 ± 0.0002 respectively. The small uncertainties in γ suggest a precise procedure while the discrepancy between experimental and accepted values indicates inaccuracy. Systematic errors are suggested; however it was noted that an average discrepancy of 0.18 between accepted and experimental values occurred. If this difference is accounted for, it can be seen that we measure lower vibrational contributions to γ at room temperature than those predicted by the equipartition principle. It can be therefore deduced that the classical idea of all modes contributing to γ is incorrect and there is actually a „freezing out‟ of vibrational modes at lower temperatures. I. Introduction II. Method The primary objective of this experiment was to determine the ratio of specific heats, γ, for gaseous Ar, N2, CO2 and an Ar + N2 mixture. -
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. -
Artificial Cell Research As a Field That Connects Chemical, Biological and Philosophical Questions
Zurich Open Repository and Archive University of Zurich Main Library Strickhofstrasse 39 CH-8057 Zurich www.zora.uzh.ch Year: 2016 Artificial cell research as a field that connects chemical, biological and philosophical questions Deplazes-Zemp, Anna Abstract: This review article discusses the interdisciplinary nature and implications of artificial cell research. It starts from two historical theories: Gánti’s chemoton model and the autopoiesis theory by Maturana and Varela. They both explain the transition from chemical molecules to biological cells. These models exemplify two different ways in which disciplines of chemistry, biology and philosophy canprofit from each other. In the chemoton model, conclusions from one disciplinary approach are relevant for the other disciplines. In contrast, the autopoiesis model itself (rather than its conclusions) is transferred from one discipline to the other. The article closes by underpinning the relevance of artificial cell research for philosophy with reference to the on-going philosophical debates on emergence, biological functions and biocentrism. DOI: https://doi.org/10.2533/chimia.2016.443 Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-135057 Journal Article Published Version Originally published at: Deplazes-Zemp, Anna (2016). Artificial cell research as a field that connects chemical, biological and philosophical questions. CHIMIA International Journal for Chemistry, 70(6):443-448. DOI: https://doi.org/10.2533/chimia.2016.443 NCCR MoleCulaR SySteMS eNgiNeeRiNg CHIMIA 2016, 70, No. 6 443 doi:10.2533/chimia.2016.443 Chimia 70 (2016) 443–448 © Swiss Chemical Society Artificial Cell Research as a Field that Connects Chemical, Biological and Philosophical Questions Anna Deplazes-Zemp* Abstract: This review article discusses the interdisciplinary nature and implications of artificial cell research. -
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. -
Inhibition of Premixed Carbon Monoxide-Hydrogen-Oxygen-Nitrogen Flames by Iron Pentacarbonylt
Inhibition of Premixed Carbon Monoxide-Hydrogen-Oxygen-Nitrogen Flames by Iron Pentacarbonylt MARC D. RUMMINGER+ AND GREGORY T. LINTERIS* Building and Fire Research Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA This paper presents measurements of the burning velocity of premixed CO-HrOrNz flames with and without the inhibitor Fe(CO)s over a range of initial Hz and Oz mole fractions. A numerical model is used to simulate the flame inhibition using a gas-phase chemical mechanism. For the uninhibited flames, predictions of burning velocity are excellent and for the inhibited flames, the qualitative agreement is good. The agreement depends strongly on the rate of the CO + OH <-> COz + H reaction and the rates of several key iron reactions in catalytic H- and O-atom scavenging cycles. Most of the chemical inhibition occurs through a catalytic cycle that converts o atoms into Oz molecules. This O-atom cycle is not important in methane flames. The H-atom cycle that causes most of the radical scavenging in the methane flames is also active in CO-Hz flames, but is of secondary importance. To vary the role of the H- and O-atom radical pools, the experiments and calculations are performed over a range of oxygen and hydrogen mole fraction. The degree of inhibition is shown to be related to the fraction of the net H- and O-atom destruction through the iron species catalytic cycles. The O-atom cycle saturates at a relatively low inhibitor mole fraction (-100 ppm), whereas the H-atom cycle saturates at a much higher inhibitor mole fraction (-400 ppm).