Biology Chapter 2 Extra Credit

1. a compound that can bind to an H+ ion when the H+ concentration increases and can release H+ ion when the H+ concentration decreases.
4. the substances changed during a chemical reaction.
5. two or more atoms held together by covalent bonds.
8. measurement of acidity; related to free hydrogen ion concentration in solution.
11. a large molecule or macromolecule made of many monomers bonded together.
13. amino acids form covalent bonds.
15. the substances made during a chemical reaction.
17. forms when atoms share a pair of electrons.
19. The attraction among the molecules of a substance.
20. The attraction among molecules of different substances.
23. reached when both the reactants and products are made at the same rate.
24. forms through the electrical force between oppositely charged ions.
27. the smallest basic unit of matter.
28. an atom that has gained or lost one or more electrons.
30. catalysts for chemical reactions in living things.
31. molecules composed of carbon, hydrogen, oxygen, and they include sugars and starches.
32. a compound that releases a proton – hydrogen ion (H+) – when it dissolves in water. An acid increases the concentration of H+ ions in a solution.

2. chemical reaction absorbs more energy than it releases.
3. chains of carbon atoms bonded to hydrogen atoms.
6. substance made of one type of atom that cannot be broken down by chemical means.
7. a substance made of atoms of different elements bonded together in certain ratio.
9. is an attraction between a slightly positive hydrogen and a slightly negative atom, often oxygen or nitrogen.
10. chemical reaction releases more energy than it absorbs.
12. nonpolar molecules that include fats, oils, and cholesterol.
14. subunit in a molecule.
16. a mixture of substances that is the same throughout. It is a homogeneous mixture.
18. a polymer made of monomers called amino acids.
21. composed of a sugar, a phosphate group, and a nitrogen containing molecule called a base.
22. the amount of energy that will break a bond between two atoms.
25. a substance that decreases the activation energy needed to start a chemical reaction.
26. molecules that contain carbon, hydrogen, oxygen, nitrogen and sometimes sulfur.
29. compounds that remove H+ ions from a solution. When a base dissolves in water, the solution has a low H+ concentration.