1. acid - compound that forms hydrogen ions (H+) in solution.
2. activation energy - energy needed to get a reaction started.
3. adhesion - attraction between molecules of different substances; in plants, attraction between unlike molecules.
4. amino acid - compound with an amino group (--NH2) on one end and a carboxyl group (--COOH) on the other end.
5. atom - basic unit of matter.
6. base - compound that produces hydroxide ions (OH-) in solution.
7. buffer - weak acid or base that can react with strong acids or bases to help prevent sharp, sudden changes in pH.
8. carbohydrate - compound made up of carbon, hydrogen, and oxygen atoms; major source of energy for the human body.
9. catalyst - substance that speeds up the rate of a chemical reaction.
10. chemical reaction - process that changes one set of chemicals into another set of chemicals.
11. cohesion - attraction between molecules of the same substance.
12. compound - substance formed by the chemical combination of two or more elements in definite proportions.
13. covalent bond - bond formed by the sharing of electrons between atoms.
14. deoxyribonucleic acid - (DNA) nucleic acid that contains the sugar deoxyribose.
15. electron - negatively charged particle; located outside the atomic nucleus.
16. element - substance consisting entirely of one type of atom.
17. enzyme - protein that acts as a biological catalyst.
18. ion - atom that has a positive or negative charge.
19. ionic bond - bond formed when one or more electrons are transferred from one atom to another.
20. isotope - atom of an element that has a number of neutrons different from that of other atoms of the same element.
21. lipid - macromolecule made mainly from carbon and hydrogen atoms; includes fats, oils, and waxes.
22. mixture - material composed of two or more elements or compounds that are physically mixed together but not chemically combined.
23. molecule - smallest unit of most compounds.
24. monomer - small unit that can join together with other small units to form polymers.
25. monosaccharide - single sugar molecule.
26. nucleic acid - macromolecule containing hydrogen, oxygen, nitrogen, carbon, and phosphorus.
27. nucleotide - monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base.
28. nucleus - the center of the atom which contains the protons and neutrons; in cells, structure that contains the cell's genetic material (DNA) and controls the cell's activities.
29. pH scale - measurement system used to indicate the concentration of hydrogen ions (H=) in solution; ranges from 0-14.
30. polymer - large compound formed from combinations of many monomers.
31. polysaccharide - large macromolecule formed from monosaccharides.
32. product - element or compound produced by a chemical reaction.
33. protein - macromolecule that contains carbon, hydrogen, oxygen, and nitrogen; needed by the body for growth and repair and to make up enzymes.
34. reactant - element or compound that enters into a chemical reaction.
35. ribonucleic acid - (RNA) - single-stranded nucleic acid that contains the sugar ribose.
36. solute - substance that is dissolved in a solvent to make a solution.
37. solution - mixture of two or more substances in which the molecules of the substances are evenly distributed.
38. solvent - substance in which a solute is dissolved to form a solution.
39. substrate - reactant of an enzyme-catalyzed reaction.
40. suspension - mixture of water and nondissolved materials.
41. van der Waals forces - a slight attraction that develops between the oppositely charged regions of nearby molecules.
2. activation energy - energy needed to get a reaction started.
3. adhesion - attraction between molecules of different substances; in plants, attraction between unlike molecules.
4. amino acid - compound with an amino group (--NH2) on one end and a carboxyl group (--COOH) on the other end.
5. atom - basic unit of matter.
6. base - compound that produces hydroxide ions (OH-) in solution.
7. buffer - weak acid or base that can react with strong acids or bases to help prevent sharp, sudden changes in pH.
8. carbohydrate - compound made up of carbon, hydrogen, and oxygen atoms; major source of energy for the human body.
9. catalyst - substance that speeds up the rate of a chemical reaction.
10. chemical reaction - process that changes one set of chemicals into another set of chemicals.
11. cohesion - attraction between molecules of the same substance.
12. compound - substance formed by the chemical combination of two or more elements in definite proportions.
13. covalent bond - bond formed by the sharing of electrons between atoms.
14. deoxyribonucleic acid - (DNA) nucleic acid that contains the sugar deoxyribose.
15. electron - negatively charged particle; located outside the atomic nucleus.
16. element - substance consisting entirely of one type of atom.
17. enzyme - protein that acts as a biological catalyst.
18. ion - atom that has a positive or negative charge.
19. ionic bond - bond formed when one or more electrons are transferred from one atom to another.
20. isotope - atom of an element that has a number of neutrons different from that of other atoms of the same element.
21. lipid - macromolecule made mainly from carbon and hydrogen atoms; includes fats, oils, and waxes.
22. mixture - material composed of two or more elements or compounds that are physically mixed together but not chemically combined.
23. molecule - smallest unit of most compounds.
24. monomer - small unit that can join together with other small units to form polymers.
25. monosaccharide - single sugar molecule.
26. nucleic acid - macromolecule containing hydrogen, oxygen, nitrogen, carbon, and phosphorus.
27. nucleotide - monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base.
28. nucleus - the center of the atom which contains the protons and neutrons; in cells, structure that contains the cell's genetic material (DNA) and controls the cell's activities.
29. pH scale - measurement system used to indicate the concentration of hydrogen ions (H=) in solution; ranges from 0-14.
30. polymer - large compound formed from combinations of many monomers.
31. polysaccharide - large macromolecule formed from monosaccharides.
32. product - element or compound produced by a chemical reaction.
33. protein - macromolecule that contains carbon, hydrogen, oxygen, and nitrogen; needed by the body for growth and repair and to make up enzymes.
34. reactant - element or compound that enters into a chemical reaction.
35. ribonucleic acid - (RNA) - single-stranded nucleic acid that contains the sugar ribose.
36. solute - substance that is dissolved in a solvent to make a solution.
37. solution - mixture of two or more substances in which the molecules of the substances are evenly distributed.
38. solvent - substance in which a solute is dissolved to form a solution.
39. substrate - reactant of an enzyme-catalyzed reaction.
40. suspension - mixture of water and nondissolved materials.
41. van der Waals forces - a slight attraction that develops between the oppositely charged regions of nearby molecules.