Elements of Life

12 Key excerpts on "Elements of Life"

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  Scientific Principles for Physical Geographers

  • Ian Bradbury, John Boyle, Andy Morse(Authors)
  • 2014(Publication Date)
  • Routledge

    (Publisher)

  32Life’s chemistry

  32.1 The chemical Elements of Life

  Organisms have made use of around one-quarter of the ninety or so naturally occurring chemical elements on the planet. Most of these elements are required by all organisms, but a few of them are required by some organisms and not by others. The elements, which are often called the nutrient elements, inorganic nutrients or bioelements , are shown in Table 32.1 , together with their chemical symbols.

  The list of elements in Table 3.1 reveals that all but four of the bioelements have an atomic number of 30 or less and comparatively low relative atomic masses. It thus appears that the size and mass of nuclei have been important factors in their appropriation for life processes. The chemical analysis of living tissue usually reveals the presence of a few other elements in addition to those listed. In the case of a plant, they may have been taken up by the roots, and in the case of an animal, consumed with the food. Some such elements, lead and cadmium for example, are toxic and may harm the organisms concerned, or those other organisms which feed upon them. Also, note that some of the essential elements, zinc and copper for example, are harmful if present in relatively high concentrations.

  32.2 Carbon

  The chemistry of life is intimately associated with the chemistry of carbon compounds. (However, it should not be forgotten that some of the many other elements which organisms require are not necessarily always bound to organic molecules.) Carbon accounts for approximately 45 per cent of the dry mass of the Earth’s biota, although the percentage varies between different types of organism. Because carbon is so fundamental to life, the term ‘organic chemistry’ was coined early by chemists to distinguish this branch of the discipline from inorganic chemistry, which deals with all other compounds. However, large compounds containing carbon are produced synthetically, so organic chemistry is no longer solely concerned with the chemistry of life. We describe in more detail some general properties of carbon in 16 . Key points are that carbon atoms (atomic number 6), with four electrons in the valence shell, form stable bonds with each other, and these may be single, double or even triple bonds. The molecules so formed may be long chains (which may be branched or unbranched), they may be rings, or they may be more complex structures. Carbon also forms stable bonds with certain other elements, particularly oxygen (single and double bonds), hydrogen (single bonds), nitrogen (double and triple bonds) and sulphur (single bonds). The size of carbon compounds varies enormously. Some of the main ones that we consider contain just a few carbon atoms but others contain many thousands. In illustrating some of the more common compounds we use the conventions introduced when we discussed organic chemistry (see 16.3

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  Color Atlas of Biochemistry

  • Jan Koolman, Klaus-Heinrich Röhm(Authors)
  • 2012(Publication Date)
  • Thieme

    (Publisher)

  Basics Chemistry 2 Chemistry Periodic Table A. Biologically important elements There are 81 stable elements in nature. Fifteen of these are present in all living things, and a further 8–10 are only found in particular or-ganisms. The illustration shows the first half of the periodic table, containing all of the biologi-cally important elements. In addition to physi-cal and chemical data (atomic number, relative atomic mass, group and electron configura -tion), it also provides information about the distribution of the elements in the living world and how abundantly they occur in the human body. More than 99% of the atoms in animals’ bodies are accounted for by just four elements—hy-drogen (H), oxygen (O), carbon (C) and nitro-gen (N). Hydrogen and oxygen are the constit-uents of water , which alone makes up 60%– 70% of cell mass (see p. 196). Together with carbon and nitrogen, these atoms are also the major constituents of the organic compounds on which most living processes depend. Many biomolecules also contain sulfur (S) or phos-phorus (P). The above macroelements are es-sential for all organisms. A second biologically important group of ele-ments, which together represent only about 0.5% of the body, are present almost exclu-sively in the form of inorganic ions. These are known as electrolytes and include the alkali metals sodium (Na) and potassium (K), and the alkaline earth metals magnesium (Mg) and cal-cium (Ca). The halogen chlorine (Cl) is also al-ways ionized in the cell. All other elements important for life are present in such small quantities that they are referred to as trace ele-ments (p. 384). These include transition metals such as iron (Fe), zinc (Zn), copper (Cu), cobalt (Co) and manganese (Mn). A few nonmetals, such as iodine (I) and selenium (Se), can also be classed as essential trace elements.

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  Essentials of Medical Geology

  Impacts of the Natural Environment on Public Health

  • (Author)
  • 2005(Publication Date)
  • Academic Press

    (Publisher)

  This chapter begins with a discussion of the periodic table and what is meant by essentiality . I. Essentiality of Elements A usually ignored fact in biology is that explanations for the behavior of elements can be found in the periodic table itself. Among the elements known to be involved in biology, 11 appear to be approximately constant and predominant in all biological systems. The human body is comprised of about 99.9% of the 11 elements, but surprisingly only 4 of them—hydrogen, carbon, nitro-gen, and oxygen—account for 99% of the total. These 4 elements, the major elements, comprise the bulk of living organisms. In addition to these elements, there are the minor elements—sodium, magnesium, phos-phorus, sulfur, chlorine, potassium, and calcium (also called electrolytes ). The minor elements appear in much lower concentration than major elements. One group of elements has still to be defined: the trace elements. 87 Essentials of Medical Geology Copyright © 2005, Elsevier Inc. All rights reserved. Chapter 5 Uptake of Elements from a Biological Point of View Ulf Lindh Uppsala University From an analytical chemistry standpoint, trace elements would be described as elements appearing in low con-centrations in living systems ( i.e. , < 100 mg/kg). In biology, however, trace elements would be defined by exclusion; for example, a biological approach begins by excluding the major elements as well as the minor ele-ments. Furthermore, group 18 elements (the noble gases) are excluded due to their disinclination for chem-ical reactions, a property that makes these elements less likely to be a factor in biological functions. Depending on how many elements are considered naturally occur-ring, the trace elements thus constitute the remainder of the periodic table ( i.e. , 73 or 75 elements). Most of the elements of the periodic table, then, are trace elements in the eyes of a biologist.

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  Concepts of Biology

  • Samantha Fowler, Rebecca Roush, James Wise(Authors)
  • 2016(Publication Date)
  • Openstax

    (Publisher)

  2 | CHEMISTRY OF LIFE Figure 2.1 Foods such as bread, fruit, and cheese are rich sources of biological macromolecules. (credit: modification of work by Bengt Nyman) Chapter Outline 2.1: The Building Blocks of Molecules 2.2: Water 2.3: Biological Molecules Introduction The elements carbon, hydrogen, nitrogen, oxygen, sulfur, and phosphorus are the key building blocks of the chemicals found in living things. They form the carbohydrates, nucleic acids, proteins, and lipids (all of which will be defined later in this chapter) that are the fundamental molecular components of all organisms. In this chapter, we will discuss these important building blocks and learn how the unique properties of the atoms of different elements affect their interactions with other atoms to form the molecules of life. Food provides an organism with nutrients—the matter it needs to survive. Many of these critical nutrients come in the form of biological macromolecules, or large molecules necessary for life. These macromolecules are built from different combinations of smaller organic molecules. What specific types of biological macromolecules do living things require? How are these molecules formed? What functions do they serve? In this chapter, we will explore these questions. Chapter 2 | Chemistry of Life 27 2.1 | The Building Blocks of Molecules By the end of this section, you will be able to: • Describe matter and elements • Describe the interrelationship between protons, neutrons, and electrons, and the ways in which electrons can be donated or shared between atoms At its most fundamental level, life is made up of matter. Matter occupies space and has mass. All matter is composed of elements, substances that cannot be broken down or transformed chemically into other substances. Each element is made of atoms, each with a constant number of protons and unique properties. A total of 118 elements have been defined; however, only 92 occur naturally, and fewer than 30 are found in living cells.

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  Pharmacology and Nutritional Intervention in the Treatment of Disease

  • Faik Atroshi(Author)
  • 2014(Publication Date)
  • IntechOpen

    (Publisher)

  vulnerable to external influence. Since the general conditions of biological evolution (the composition of biosphere), are continuously changing, a set of bioelements in a living organism can also change. This distinguishes them from chemical elements as objects of physicochemical stage, which remain identical to themselves along the course of evolution. So, bioelement is the elemental functioning unit of living matter, which is a biologically active complex of chemical elements as atoms, ions and nanoparticles with organic compounds of exogenous (primary) or biogenous (secondary) origin [3]. In principle, bioelements include any chemical structures found in living nature, but which do not have a set of fundamental properties of living things: metabolism, variability, reproduction and heredity. Primarily, these are organogens (C, H, N, O), P, S and representatives of four classes of small organic molecules which compose the cells: amino acids, nucleotides, sugars, fatty acids, – and coordination structures, aquated ions of vital macro and trace elements and water as well. Bioelement is not a chemical element inside a molecular compound, but it is temporarily formed biocomplex, where the chemical element is bound by covalent (chelate) bond to the organic molecule. They should not be considered separately, because, interacting, together they produce biological effect of new quality [5]. If chemical element is a physicochemical unit of the matter’s evolution, then bioelement – is a precursor of a biological unit, which has physicochemical nature. Fundamental differences between chemical elements and their compounds in abiogenic media and bioelements are described in Table 1. Bioelements can continuously form from ionic compounds when they enter the cell. Inside the cell, biopolymers and their complexes create a complicated, coordinated and regulated system for transformation of substances.

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  Ecological Stoichiometry

  The Biology of Elements from Molecules to the Biosphere

  • Robert W. Sterner, James J. Elser(Authors)
  • 2017(Publication Date)
  • Princeton University Press

    (Publisher)

  2 Biological Chemistry: Building Cells from Elements Phosphorus has a special function among the substances assimilated by living things: carbon, hydrogen, oxygen and nitrogen are the elements of biological frameworks, phosphorus is the instrument of their manufacture.—Pautard ( 1978 ) The fact that the chemical composition of organisms differs in many ways from that of the nonliving world (Table 1.1) implies a “natural selection of the elements” (Williams and Fra ´ usto da Silva 1996). In other words, the elements used extensively by biological systems are not an unbiased sample from the periodic table or from the abiotic world. Indeed, a distinct stoichiometric signature of living systems is one tool that has been used to separate life from nonlife in ancient fossilized material (Watanabe et al. 2000). The physical chemistry of an element directly determines the types of interactions it has with other elements and thus the sorts of chemical and biochemical functions that element can perform for the organism (the self-maintaining and self-regenerating suite of chemical compounds and reactions with which it is associated). Early chemical evolution and subsequent biological evolution in response to major changes in environmental conditions (e.g., changes in atmo-spheric oxygen levels or aqueous redox conditions) involved selection of ele-ments from the array presented by the external geochemical environment. Both in the universe as a whole and in earthly biomass, lighter elements predominate (Table 1.1). Also, atoms with even atomic numbers are generally more numerous than those with odd numbers (a consequence of the creation of heavy elements via fusion of He nuclei).

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  Metallomics

  A Primer of Integrated Biometal Sciences

  • Wolfgang Maret(Author)
  • 2016(Publication Date)
  • WSPC

    (Publisher)

  The way such biological PSEs are usually presented generates considerable confusion due to at least three issues. First, the essential elements are given without reference to a specific form of life. Instead, what is presented is the sum of all elements essential for life despite the fact that the number of essential elements differs in organisms. Second, a clear definition is lacking what “essential” actually means, an issue that is discussed in the next chapter. Moreover, the relative biological significance of the elements is not apparent from such a presentation. Elements with critical general functions are mixed with those that have only very specific functions. Third and remarkably, it is often overlooked that many more metals and elements than just the essential ones are present in organisms and that their presence is often associated with functional outcomes (Table 3.2 ; Haraguchi et al. 2008; Roverso et al. 2015; Emsley 2001). Determining elements in biological material, of course, is a matter of sensitivity of the methods — an increasing number of elements can be found with increasing sensitivity. Organisms have the capability of metabolising, i.e. chemically modifying elements and their species, which is not evidence by itself for these elements having an essential function. For example, bacteria methylate mercury compounds and organisms synthesize arsenic-containing sugars and lipids. Such reactions are also part of the inorganic biochemistry of life. It is instructive to collect the information about the abundance of elements in humans in the PSE (Figure 3.11). Nobel laureate Francis William Aston (1877–1945) determined the abundance of the elements on earth and found that it decreases with increasing atomic number. It is therefore not surprising to find that most of the abundant elements are employed in life with the notable exception of aluminium. On the other hand, some elements that are quite rare, e.g

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  Trace Elements in Human and Animal Nutrition

  • E Underwood(Author)
  • 2012(Publication Date)
  • Academic Press

    (Publisher)

  I. THE NATURE OF TRACE ELEMENTS Many mineral elements occur in living tissues in such small amounts that the early workers were unable to measure their precise concentrations with the analytical methods then available. They were therefore frequently described as occurring in traces and the term trace elements arose to describe them . This designation has remained in popular usage despite the fact that virtually all the trace elements can now be estimated in biological materials with great accuracy and precision. It is retained here because it is brief and has become hallowed by time. It is difficult to find a meaningful classification for the trace elements or even to draw a completely satisfactory line of demarcation between those so desig-nated and the so-called major elements. At the present time 26 of the 90 naturally occurring elements are known to be essential for animal life. These consist of 11 major elements, namely, carbon, hydrogen, oxygen, nitrogen, sulfur, calcium, phosphorus, potassium, sodium, chlorine, and magnesium, and 15 elements generally accepted as trace elements. These are iron, zinc, copper, manganese, nickel, cobalt, molybdenum, selenium, chromium, iodine, fluorine, tin, silicon, vanadium, and arsenic. In addition, boron is essential for the higher plants but has not yet been shown to be necessary for animals. It is clear that evolution has selected certain elements for the essential functioning of living organisms and has, on present evidence, rejected or ignored others. The molecular basis for this selection or rejection is far from clear. In this 1 1 Introduction 2 1. Introduction connection it should be noted that only three of the 27 elements now known to be essential for life, i.e., iodine, tin, and molybdenum, have an atomic number above 34, and a considerable proportion of the essential trace elements occupy positions in the Periodic Table between atomic numbers 23 and 34.

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  Visualizing Microbiology

  • Rodney P. Anderson, Linda Young, Kim R. Finer(Authors)
  • 2020(Publication Date)
  • Wiley

    (Publisher)

  As a result, we can use microbes to remediate polluted habitats and work to preserve the microbial communities that are the foundation of all ecosystems. Elements and the Periodic Table Chemistry is the study of matter, which is defined as anything that takes up space and has mass. The smallest units of matter, atoms, are often referred to as building blocks because connect- ing atoms allows the construction of important molecules that make up microorganisms. All atoms of a specific kind are known as an element, which is a pure substance that cannot be broken down by ordinary chemical means. There are approximately 92 naturally occurring elements plus more than a dozen created in the laboratory. Despite the amazing diversity of organisms on our planet, all are composed of about 25 different elements in approximately the same proportions (Figure 2.1). Each element is assigned a chemical symbol based on its name. Carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P), and sulfur (S) are the most common elements found in all living things and are represented by chemical sym- bols that are the first letter of their names. Because there are about four times more elements than there are letters in the alphabet, many chemical symbols consist of the first two let- ters of an element’s name. For example, calcium, another com- mon biologically significant element, is designated as Ca. The abbreviations used for some chemical symbols are derived from either the Latin or Germanic version of an element’s name. For convenience, all of the elements are arranged in a highly organized periodic table in rows based on increasing size. The columns of the table contain elements with potentially similar chemical properties (Figure 2.2). For example, the column with F (fluorine), Cl (chlorine), Br (bromine) and I (iodine) all have strong antimicrobial activity.

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  The Chemistry of Evolution

  The Development of our Ecosystem

  • R.J.P Williams, J.J.R Fraústo da Silva(Authors)
  • 2005(Publication Date)
  • Elsevier Science

    (Publisher)

  First, we must look at the value of the original available elements which were taken into or rejected by organisms. Afterwards, we shall look at the way the originally available elements could form the essential compounds we observe in all life (Table 4.4); then we must ask about organisation. (see Section 4.20). 4.4. The Functional Value of the Elements in Organisms: Introduction to Biological Compounds We turn now to the essential ways the elements are used in biological chemistry. Rather than taking all the elements together, we shall look at two sets of them sep-arately – the non-metals and the metals – indicating the common types of com-pound in which they are found in all cells. This separation makes a clear connection to the description of the chemistry of the elements in Chapter 2. We shall see that their conditions are energised in different ways. We shall look at these compounds and their use in cells while asking whether or not there is likely to be equilibrium between their binding sites within any aqueous compartment, also across membranes and even with their small ion or molecular states as found in the environment. This is a considerable concern in thermodynamics (see Section 3.14). The parallels with the different chemistry of non-metals and metals (in organic and Outline of Biological Chemical Principles 137 TABLE 4.4 C OMPONENTS IN A T YPICAL S IMPLE (B ACTERIAL ) C ELL Component Numbers Variety Proteins (proteome) 2.5 10 6 3,000 DNA (genome) 1(2) 1 m-RNA 4,000 2,000 Ribosomes 10,000 2 Peptidoglycan 1 1 (wall) Metabolites (metabolome) 3 10 8 10 3 Lipid 2 10 6 2? Water 5 10 10 1 Metal ions (metallome) 10 7 12 Note : See Harold in Further Reading for data on E. coli . inorganic chemistry) as introduced in Chapter 2 will be clear, but as stated there we shall have to bring these chemistries together before the end of the chapter.

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  Animate Earth

  Science, Intuition and Gaia

  • Stephan Harding(Author)
  • 2009(Publication Date)
  • Green Books

    (Publisher)

  Chapter 4 Life and the Elements Atoms as Beings In order to deeply understand the life of our planet we need to explore the cycles of the chemical elements, for without their coming to life in organ- isms there would be no Gaia to speak of. So what exactly are the chem- ical elements? Democritus was right—the material world is indeed made of atoms, but, as we have seen, atoms are not dead, mechanical entities; they are participatory beings with characters akin to our own, even though those of atoms are far more consistent than human nature, which is malleable, often unpredictable, and very much dependent on circum- stance. Place the same person in the same environment today and tomorrow, and on one day they may feel good, on the other they may feel sad. According to mainstream science, atomic personalities are far more consistent—an oxygen atom will always behave in the same way whenever it encounters the same chemical and physical environment, no matter where in the universe the encounter happens. Every person (and indeed, every mammal, bird, reptile, and possibly insect) has a unique character— no two hummingbirds will behave in exactly the same way, but every Life and the Elements 93 oxygen atom is considered to have exactly the same response, the same character everywhere throughout the universe. This does not mean that atoms, or the protons, neutrons and electrons that constitute them, are no more than totally isolated, independent, self- existing entities interacting like billiard balls in totally predictable ways. Modern physics shows us that nothing in the universe exists in splendid isolation—everything depends for its very existence on its relationships with everything else. When a hydrogen atom bonds with an oxygen atom, aspects of the personalities of hydrogen and oxygen are brought out in the relationship which are not present in oxygen and hydrogen alone.

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  Mineral Nutrition of Animals

  Studies in the Agricultural and Food Sciences

  • V. I. Georgievskii, B. N. Annenkov, V. T. Samokhin(Authors)
  • 2013(Publication Date)
  • Butterworth-Heinemann

    (Publisher)

  A comparison of the elemental chemical composition of the lithosphère and biosphere (Table 3.1) shows that the major elements present in living organisms are those which readily form gases under biospheric conditions and are highly soluble. The concentration of such elements (e.g., Ν, H, P, S, CI) in the organism is much higher than in the Earth's crust. On the other hand, the concentration of elements whose compounds are not mobile (As, Si, Ti, etc.) in the organism is small or negligible, while their abundance in the Earth's crust is fairly high. This comparison may be taken further. While the quantitative rela-tionships between individual elements may vary, in the final count, the elemental chemical composition of animals and plants will clearly be the same as that of inorganic matter - the Earth's crust, water and atmosphere. The above is an expression of Vernadskii's theory of the dispersion of chemical elements in nature ('all elements are found everywhere'). The geochemical processes, which are continuously taking place in the Earth's crust, and the evolution of the chemical composition of living organisms are conjugated processes. 57 BIOGEOCHEMICAL REGIONS. MINERAL COMPOSITION OF FEEDS 58 Biogeochemical regions. Mineral composition of feeds Table 3.1 ELEMENTAL COMPOSITION OF THE BIOSPHERE A N D LITHOSPHERE Biosphere (animal Lithosphère kingdom) (g%) kingdom) (g%) Earth's crust (g%) Water and air (g%) Oxygen 63.43 Oxygen 46.68 Atmosphere* Carbon Hydrogen Nitrogen Calcium 20.20 9.90 3.06 1.64 Silicon Aluminium Iron Calcium 27.00 8.05 5.03 3.63 Nitrogen Oxygen Rare gases Carbon 75.42 23.26 1.30 0.02 Phosphorus Potassium 1.0 0.20 Sodium Potassium 2.72 2.56 Hydrogen 0.0007 Sulphur 0.16 Magnesium 2.35 Seawater Sodium 0.16 Titanium 0.70 Seawater Chlorine 0.12 Phosphorus 0.15 Oxygen 85.96 Magnesium 0.05 Carbon 0.15 Hydrogen 10.78 Microelements 0.12 Hydrogen 0.11 Chlorine 1.89 incl.

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