Bio Terms

  1. Element
    • substance that cannot be broken down chemically into any other
    • substances. Gold, carbon, and copper are elements you might be
    • familiar with.
    • - each element has an atomic number –
    • corresponds with the number of protons
  2. Atom
    • a
    • bit of matter that cannot be subdivided any further without losing
    • its essential properties. The word “atom” is from the Greek for
    • “indivisible.”
  3. nucleus
    • center of an atom, made of 2 types of particles called protons and neutrons
    • small and compact - leaves a lot of space for neutrons to zip around
  4. Protons
    particles with positive electrical charge
  5. Neutrons
    • particles with no electrical charge
    • usually about same of each in an atom
  6. mass
    • amount of matter in a particle
    • protons and neutrons together
    • number of protons determines the element
  7. Electrons
    • whirling in a cloud around nucleus - negatively charged
    • weighs almost nothing - less than 1/20th of protons
  8. atomic mass
    made of combined mass of all protons and neutrons
  9. Isotope
    • atom with less or more neutrons than protons (rare)
    • carbon -13 and carbon -14 "heavy carbon"
    • same atomic number, diff mass
  10. Radioactive atoms
    • in the process of decomposition they realease
    • tiny high speed particles carrying a lot of energy
    • useful for determining age of fossils, cancer treatment, vast amount of energy
  11. Periodic table
    elements arranged according to their atomic number
  12. the Big 4
    • element that make our body
    • oxygen, hydrogen, nitrogen and carbon
    • 96% of body mass
  13. Electron Shell
    • Electrons stay within prescribed area in an atom - the shell
    • each electron has its own shell
    • electrons stay far apart because their negative charge repels them
  14. 2 and 8
    • First shell of the atom has most of the time has 2 netrons, every other shell 8
    • can have up to 7 shells
  15. What does chem charac of an atom depend on
    • number of electrons in most outer shell
    • most stable when all electrons are filled
  16. Molecules
    hold atoms together by bonds
  17. Bond energy
    the energy with which atoms are held together
  18. Covalent Bond
    • a strong bond formed when atoms share electrons to become more stable - form a molecule (attach)
    • ex. H2
  19. Ionic Bond
    • an attraction btw 2 oppositely charged ions - forming a compound
    • - atom gaining an atom will be - negatively charged
    • losing - positively
  20. Compound
    a molecule made of 2 or more parts
  21. Hydrogen Bonds
    • weak bond
    • between slightly positively charged hydrogen atom of one molecule and slightly negatively charged atom of another
  22. Polar Molecules
    • attracted to other polar molecules
    • line up in particular orientation such that the positive regions of molecule are near negative of another
  23. Water Molecules are polar, Why?
    because of their unequally shared electrons
  24. What do hydrogen bonds give water?
    • cohesiveness
    • reduced density
    • ability to resist temperature changes
    • effectiveness as a solvent for ionic and polar substances
  25. what is pH
    the amount of H+ in a solution is a measure of acidity
  26. What is Acid
    • Any fluid with a pH
    • below 7.0 has more H+ ions (and fewer OH−
    • ions)
  27. What is Base
    • Any fluid with a pH
    • above 7.0 has fewer H+ ions (and more OH−
    • ions)
  28. Levels of acidity
    • the lower the number the greater the acidity
    • a decrease of 1 on the pH scale represents 10-fold increase in the hydrogen ion concentration
  29. buffers
    • chemicals that absorb excess H+ ions to keep a solution from becoming too acidic
    • chemicals that act to resist changes in pH
  30. pH of a fluid
    measure how acidic or basic the solution is
  31. macromolecules
    • large molecules made up from smaller building blocks or subunits—are
    • essential to the building and functioning of living organisms:
    • carbohydrates, lipids, proteins, and nucleic acids.
  32. Carbohydrates
    • molecules that contain mostly carbon, hydrogen, and oxygen: they are
    • the primary fuel for running all of the cellular machinery and also
    • form much of the structure of cells in all life forms
    • not all are digestable by humans
  33. Monosaccharide (simple sugar)
    • cannot be broken
    • down into other simple sugars; examples are glucose, fructose, and
    • galactose.
  34. Glycogen
    • a web of molecules form together by stored glucose molecules
    • - prime form of short term energy storage in animals
  35. Disaccharides
    • Carbohydrates formed by the union of
    • two simple sugars, such as sucrose (table sugar) and lactose (the
    • sugar found in milk).
  36. polysaccharides
    • Complex carbohydrates formed by the
    • union of many simple sugars.
  37. Starch
    • multiple amount of simple sugars
    • primary form of energy storage in animals
  38. chitin
    • A complex carbohydrate, indigestible by
    • humans, that forms the rigid outer skeleton of most insects and
    • crustaceans.
  39. Lipid
    • One of four types of macromolecules,
    • lipids are insoluble in water and greasy to the touch; they are
    • important in energy storage and insulation (fats), membrane formation
    • (phospholipids), and regulating growth and developmen
  40. hydrophobic
    • Repelled by water, as, for example,
    • nonpolar molecules that tend to minimize contact with water
  41. hydrophillic
    • Attracted to water, as, for example,
    • polar molecules that readily form hydrogen bonds with water.
  42. glycerol
    • A small molecule that forms the head
    • region of a triglyceride fat molecule
  43. Fatty Acid
    • A long hydrocarbon (a chain of
    • carbon-hydrogen molecules); fatty acids form the tail region of
    • triglyceride fat molecules.
  44. Enzymes
    proteins that help initiate and speed up chemical reaction
  45. Neucleic acids
    store info on how to run the body
  46. RNA
    • universal translator of genetic code into proteins
    • reads DNA - produces AMINO acids
  47. Sterol
    lipid important in growth in development
  48. subtrate
    molecule on which the enzyme acts
  49. tertiary structure
    • The unique and complex three-dimensional shape formed by multiple twists
    • of the secondary structure of a protein as amino acids come together
    • and form hydrogen bonds or covalent sulfur-sulfur bonds
  50. trans fat
    An unsaturated fat that has been partially hydrogenated
  51. Triglyceride
    A fat having three fatty acids linked to the glycerol molecule
  52. wax
    A lipid similar in structure to fats but with only one long-chain fatty acid linked to the glycerol head of the molecule
Card Set
Bio Terms
bio terms