Where is the nitrogen on Mars?

2003 ◽  
Vol 2 (3) ◽  
pp. 217-225 ◽  
Author(s):  
Rocco L. Mancinelli ◽  
Amos Banin
Keyword(s):  
Organic Molecules ◽  
Essential Element ◽  
Crystal Lattices ◽  
Origin And Evolution ◽  
Thermal Escape ◽  
Martian Soil ◽  
Evolution Of Life ◽  
Life On Mars ◽  
Nitrogen Abundance ◽  
Living Organisms

Nitrogen is an essential element for life. Specifically, fixed nitrogen (i.e. NH3, NH4+, NOx or N that is chemically bound to either inorganic or organic molecules and can be released by hydrolysis to form NH3 or NH4+) is useful to living organisms. Nitrogen on present-day Mars has been analysed only in the atmosphere. The inventory is a small fraction of the amount of nitrogen presumed to have been received by the planet during its accretion. Where is the missing nitrogen? Answering this question is crucial for understanding the probability of the origin and evolution of life on Mars, and for its future astrobiological exploration. The two main processes that could have removed nitrogen from the atmosphere include: (1) non-thermal escape of N atoms to space and (2) burial within the regolith as nitrates and ammonium salts. Nitrate would probably be stable in the highly oxidized surface soil of Mars and could have served as an NO3− sink. Such accumulations are observed in certain desert environments on Earth. Some NH4+ nitrogen may also be fixed and stabilized in the soil by inclusion as a structural cation in the crystal lattices of certain phyllosilicates replacing K+. Analysis of the Martian soil for traces of NO3− and NH4+ during future missions will provide important information regarding the nitrogen abundance on Mars. We hypothesize that Mars soil, as typical of extremely dry desert soils on Earth, is likely to contain at least some of the missing nitrogen as nitrate salts and some fixed ammonium bound to aluminosilicate minerals.

scholarly journals The Role of Glycerol and Its Derivatives in the Biochemistry of Living Organisms, and Their Prebiotic Origin and Significance in the Evolution of Life

Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 86
Author(s):  
Maheen Gull ◽  
Matthew A. Pasek
Keyword(s):  
Prebiotic Synthesis ◽  
Early Earth ◽  
Origin And Evolution ◽  
Evolution Of Life ◽  
Prebiotic Molecules ◽  
Prebiotic Syntheses ◽  
Living Organisms ◽  
Glycerol Nucleic Acid ◽  
Synthesis Reactions

The emergence and evolution of prebiotic biomolecules on the early Earth remain a question that is considered crucial to understanding the chemistry of the origin of life. Amongst prebiotic molecules, glycerol is significant due to its ubiquity in biochemistry. In this review, we discuss the significance of glycerol and its various derivatives in biochemistry, their plausible roles in the origin and evolution of early cell membranes, and significance in the biochemistry of extremophiles, followed by their prebiotic origin on the early Earth and associated catalytic processes that led to the origin of these compounds. We also discuss various scenarios for the prebiotic syntheses of glycerol and its derivates and evaluate these to determine their relevance to early Earth biochemistry and geochemistry, and recapitulate the utilization of various minerals (including clays), condensation agents, and solvents that could have led to the successful prebiotic genesis of these biomolecules. Furthermore, important prebiotic events such as meteoritic delivery and prebiotic synthesis reactions under astrophysical conditions are also discussed. Finally, we have also highlighted some novel features of glycerol, including glycerol nucleic acid (GNA), in the origin and evolution of the life.

Photo-induced protein oxidation: mechanisms, consequences and medical applications

2019 ◽  
Vol 64 (1) ◽  
pp. 33-44 ◽  
Author(s):  
Eduardo Fuentes-Lemus ◽  
Camilo López-Alarcón
Keyword(s):  
Protein Oxidation ◽  
Photochemical Reactions ◽  
Medical Applications ◽  
Origin And Evolution ◽  
Direct Irradiation ◽  
Excited Species ◽  
Evolution Of Life ◽  
Living Organisms

Abstract Irradiation from the sun has played a crucial role in the origin and evolution of life on the earth. Due to the presence of ozone in the stratosphere most of the hazardous irradiation is absorbed, nonetheless UVB, UVA, and visible light reach the earth’s surface. The high abundance of proteins in most living organisms, and the presence of chromophores in the side chains of certain amino acids, explain why these macromolecules are principal targets when biological systems are illuminated. Light absorption triggers the formation of excited species that can initiate photo-modification of proteins. The major pathways involve modifications derived from direct irradiation and photo-sensitized reactions. In this review we explored the basic concepts behind these photochemical pathways, with special emphasis on the photosensitized mechanisms (type 1 and type 2) leading to protein oxidation, and how this affects protein structure and functions. Finally, a description of the photochemical reactions involved in some human diseases, and medical applications of protein oxidation are presented.

scholarly journals On the origin and evolution of life in the Galaxy

2010 ◽  
Vol 9 (4) ◽  
pp. 217-226 ◽  
Author(s):  
Michael McCabe ◽  
Holly Lucas
Keyword(s):  
Extraterrestrial Life ◽  
Evolutionary Transitions ◽  
Origin And Evolution ◽  
A Value ◽  
Evolution Of Life ◽  
Life On Mars ◽  
The Galaxy ◽  
The Origin Of Life ◽  
The Universe ◽  
Present Understanding

AbstractA simple stochastic model for evolution, based upon the need to pass a sequence of n critical steps is applied to both terrestrial and extraterrestrial origins of life. In the former case, the time at which humans have emerged during the habitable period of Earth suggests a value of n=4. Progressively adding earlier evolutionary transitions gives an optimum fit when n=5, implying either that their initial transitions are not critical or that habitability began around 6 Ga ago. The origin of life on Mars or elsewhere within the Solar System is excluded by the latter case and the simple anthropic argument is that extraterrestrial life is scarce in the Universe because it does not have time to evolve. Alternatively, the timescale can be extended if the migration of basic progenotic material to Earth is possible. If extra transitions are included in the model to allow for Earth migration, then the start of habitability needs to be even earlier than 6 Ga ago. Our present understanding of Galactic habitability and dynamics does not exclude this possibility. We conclude that Galactic punctuated equilibrium, proposed as a way round the anthropic problem, is not the only way of making life more common in the Galaxy.

Magnitude and variation of ratio of total body potassium to fat-free mass: a cellular level modeling study

2001 ◽  
Vol 281 (1) ◽  
pp. E1-E7 ◽  
Author(s):  
Zimian Wang ◽  
F. Xavier Pi-Sunyer ◽  
Donald P. Kotler ◽  
Jack Wang ◽  
Richard N. Pierson ◽  
...  
Keyword(s):  
Body Fat ◽  
Essential Element ◽  
Physiological Model ◽  
Cellular Level ◽  
Fat Free Mass ◽  
Total Body Potassium ◽  
Fluid Compartment ◽  
Total Body Fat ◽  
Total Body ◽  
Living Organisms

Potassium is an essential element of living organisms that is found almost exclusively in the intracellular fluid compartment. The assumed constant ratio of total body potassium (TBK) to fat-free mass (FFM) is a cornerstone of the TBK method of estimating total body fat. Although the TBK-to-FFM (TBK/FFM) ratio has been assumed constant, a large range of individual and group values is recognized. The purpose of the present study was to undertake a comprehensive analysis of biological factors that cause variation in the TBK/FFM ratio. A theoretical TBK/FFM model was developed on the cellular body composition level. This physiological model includes six factors that combine to produce the observed TBK/FFM ratio. The ratio magnitude and range, as well as the differences in the TBK/FFM ratio between men and women and variation with growth, were examined with the proposed model. The ratio of extracellular water to intracellular water ( E/I) is the major factor leading to between-individual variation in the TBK/FFM ratio. The present study provides a conceptual framework for examining the separate TBK/FFM determinants and suggests important limitations of the TBK/FFM method used in estimating total body fat in humans and other mammals.

Iron Homeostasis and Disorders in Dogs and Cats: A Review

2011 ◽  
Vol 47 (3) ◽  
pp. 151-160 ◽  
Author(s):  
Jennifer L. McCown ◽  
Andrew J. Specht
Keyword(s):  
Iron Deficiency ◽  
Iron Overload ◽  
Iron Homeostasis ◽  
Diagnostic Testing ◽  
Clinical Manifestations ◽  
Essential Element ◽  
The Body ◽  
Deficiency Anemia ◽  
Enzyme Systems ◽  
Living Organisms

Iron is an essential element for nearly all living organisms and disruption of iron homeostasis can lead to a number of clinical manifestations. Iron is used in the formation of both hemoglobin and myoglobin, as well as numerous enzyme systems of the body. Disorders of iron in the body include iron deficiency anemia, anemia of inflammatory disease, and iron overload. This article reviews normal iron metabolism, disease syndromes of iron imbalance, diagnostic testing, and treatment of either iron deficiency or excess. Recent advances in diagnosing iron deficiency using reticulocyte indices are reviewed.

scholarly journals The Origin and Evolution of Language and the Propagation of Organization

1970 ◽  
Vol 5 (2) ◽  
pp. 75-81 ◽  
Author(s):  
Robert K. Logan
Keyword(s):  
Knowledge Management ◽  
New Media ◽  
Evolution Of Language ◽  
Origin And Evolution ◽  
Language And Culture ◽  
Origin Of Language ◽  
Engineering Problems ◽  
Living Organisms ◽  
The Impact

In this presentation we will study propagating organization. We begin by examining the evolution and origin of language by briefly reviewing the impact of the phonetic alphabet (Logan 2004a), the evolution of notated language (Logan 2004b), the origin of language and culture (Logan 2006, 2007), the role of collaboration in knowledge management (Logan and Stokes 2004), the impact of “new media” (Logan in preparation). We will then connect this work to the propagating organization of all living organisms (Kauffman et al. in press) where we will show that information in biotic systems are the constraints that instruct living organisms how to operate. We will demonstrate that instructional or biotic information is quite different than the classical notion of information Shannon developed for addressing engineering problems in telecommunications. We also will show that biosemiosis is in some sense equivalent to propagating organization (Kauffman et al. in press). We then conclude our presentation with the speculation that there exist at least seven levels of biosemiosis.

scholarly journals Change of mineral and organic nitrogen forms in a long term fertilization experiment (literature)

2014 ◽  
pp. 43-47
Author(s):  
Judit Horváth ◽  
János Kátai
Keyword(s):  
Organic Nitrogen ◽  
Inorganic Nitrogen ◽  
Essential Element ◽  
Nitrogen Forms ◽  
Organic Form ◽  
The Sustainable Development ◽  
Nitrogen Turnover ◽  
Mineralization Processes ◽  
Living Organisms

The research topic has timeliness, since the rational utilization and protection of the soil, besides the conservation of its diverse functions is part of the sustainable development. Research of the long-term experiments is esentially important, because it can model the term effects in the same place, under the same conditions. If we want to get accurate informations about the occured changes, way and danger of changes, we should track the resupply and effect of the mineral nutrients and the removed quantity of nutrients with the harvest. Nitrogen is an essential element for living organisms, it is present in the soil mainly in organic form. In general only only a low percentage of the total nitrogent content can be used directly by plants in the soil. This inorganic nitrogen is produced by the transformation of organic contents through mineralization processes and it get into the soil by the fertilization. The plants incorporote the mineral nitrogen into our bodies. This is how nitrogen turnover is realized when mineral forms become organic and organic forms become mineral. The purpose of our paper is to make a literature before our research.

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