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The chemistry of life

The Nature of Matter. The chemistry of life. The Nature of Matter. Life depends on chemistry Living things are made from chemical compounds The study of chemistry begins with the basic unit of matter, the atom. Atoms. From the Greek word atomos , which means “unable to be cut”

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The chemistry of life

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  1. The Nature of Matter The chemistry of life

  2. The Nature of Matter • Life depends on chemistry • Living things are made from chemical compounds • The study of chemistry begins with the basic unit of matter, the atom

  3. Atoms • From the Greek word atomos, which means “unable to be cut” • Atoms are incredibly small • Place side by side, 100million atoms would make a row only about 1 centimeter long An atom contains subatomic particles that are even smaller

  4. Subatomic Particles • The subatomic particles that makes up atoms are protons, neutrons, and electrons • Protons are positively charged • Neutrons carry no charge • Electron is negatively charged

  5. Atom model 1

  6. Atom model 2

  7. Atoms • Atoms are electrically neutral because they have equal numbers of protons and electrons

  8. Elements • A chemical element is a pure substance that consists entirely of one type of atom • More than 100 elements are known, but only about two dozen are commonly found in living organisms • Elements are represented by a one- or two letter symbol • The Periodic Table shows the elements

  9. Chemical Compounds • In nature, more elements are found combined with other elements in compounds • A chemical compound is a substance formed by the chemical combination of two or more elements in definite proportions • The atoms in compounds are held together by chemical bonds

  10. Chemical Bonds • Bond formation involves the electros that surround each atomic nucleus • The electrons that are available to form bonds are called valence electrons

  11. Types of Chemical Bonds • Ionic bonds • Covalent bonds • Van deer Waals forces • The main types of chemical bonds are ionic bonds and covalent bonds

  12. Ionic bonds • An ionic bond is formed when or more electrons are transferred from one atom to another

  13. Ionic Bonds

  14. Covalent Bonds • A covalent bond forms when electrons are shared between atoms (single, double, and triple bonds) • The structure that result when atoms are joined together by covalent bonds is called a molecule

  15. Covalent bound

  16. Molecules • The molecule is the smallest unit of most compounds. • Many of the molecules in living cells are so large that they are known as macromolecules

  17. Macromolecules • They are formed by a process in which smaller molecules are put together (polymerization) • Monomers join together to form polymers

  18. Types of Macromolecules • Carbohydrates • Lipids • Nucleic acids • Proteins

  19. Carbohydrates • Living things use carbohydrates as their main source of energy. • Sugars • Starch • glucose

  20. Lipids • Lipids can be used to store energy • Some lipids are important parts of biological membranes. • Fat • Olive oil

  21. Nucleic Acid • Nucleic acids store and transmit heredity, or genetic information • DNA (deoxyribonucleic acid) • RNA (Ribonucleic acid)

  22. Proteins • Some proteins control the rate of chemical reactions and regulate cell process • Some are used to form bones and muscles • Others transport substances into and out of cells or help fight disease. • Enzymes

  23. Factors that affect the rate of chemical reactions • Temperature • pH

  24. Chemical reactions • chemical reaction is a process that changes, or transforms, one set of chemicals into another. • Chemical reactions always involve changes in the chemical bonds that join atoms in compounds

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