| N N N N N | letter |
| NAD+ reduction | chapter 9 | bio 113 | heading |
| NAD+ regeneration | chapter 9 | bio 113 | heading |
| NADH | chapter 9 | bio 113 | heading |
| NADP+ reduction | chapter 10 | bio 113 | heading |
| Natural selection | chapter 22 | bio 114 | heading |
| Natural selection | chapter 23 | bio 114 | heading |
| Natural selection, action of | chapter 23 | bio 114 | heading |
| Natural selection, modes of | chapter 23 | bio 114 | heading |
| Nature versus nurture | chapter 14 | bio 113 | heading |
| Navigation | chapter 51 | bio 114 | heading |
| Negative control | chapter 18 | bio 113 | heading |
| Nematoda, phylum | chapter 33 | bio 114 | heading |
| Nerve cord, dorsal, hollow | chapter 34 | bio 114 | heading |
| Net primary productivity | chapter 54 | bio 114 | heading |
| Neutral variation | chapter 23 | bio 114 | heading |
| Niche, ecological | chapter 53 | bio 114 | heading |
| Niche, fundamental | chapter 53 | bio 114 | heading |
| Niche, realized | chapter 53 | bio 114 | heading |
| Nitrification | chapter 54 | bio 114 | heading |
| Nitrogen assimilation | chapter 54 | bio 114 | heading |
| Nitrogen cycle, The | chapter 54 | bio 114 | heading |
| Nitrogen fixing | chapter 54 | bio 114 | heading |
| Nitrogen metabolism | chapter 27 | bio 114 | heading |
| Nitrogenous bases | chapter 5 | bio 113 | heading |
| No evolution | chapter 23 | bio 114 | heading |
| Noncompetitive inhibitors | chapter 6 | bio 113 | heading |
| Noncovalent bonds | chapter 2 | bio 113 | heading |
| Noncovalent forces | chapter 2 | bio 113 | heading |
| Noncovalent interactions | chapter 2 | bio 113 | heading |
| Non-cyclic electron flow (photosynthesis) | chapter 10 | bio 113 | heading |
| Non-Darwinian evolution | chapter 23 | bio 114 | heading |
| Nondisjunction | chapter 15 | bio 113 | heading |
| Nonkinetochore microtubules | chapter 12 | bio 113 | heading |
| Nonrandom mating | chapter 23 | bio 114 | heading |
| Nonsense codons | chapter 17 | bio 113 | term |
| Nonsense mutation | chapter 17 | bio 113 | heading |
| Norm of reaction | chapter 14 | bio 113 | heading |
| Not happening, events, calculating for | chapter 14 | bio 114 | heading |
| Notochord | chapter 34 | bio 114 | heading |
| Not-yet-complete oxidation of glucose | chapter 9 | bio 113 | heading |
| Nuclear membrane | chapter 7 | bio 113 | heading |
| Nucleic acids | chapter 5 | bio 113 | heading |
| Nucleolus | chapter 7 | bio 113 | heading |
| Nucleosides | chapter 16 | bio 113 | heading |
| Nucleosome | chapter 19 | bio 113 | heading |
| Nucleotides | chapter 5 | bio 113 | heading |
| Nucleus | chapter 7 | bio 113 | heading |
| Numbers, pyramid of | chapter 54 | bio 114 | heading |
| Nutrient, limiting | chapter 54 | bio 114 | heading |
| Nutritional deficiencies | chapter 53 | bio 114 | heading |
| Nutritional patterns | chapter 27 | bio 114 | heading |
| Nuture versus nature | chapter 14 | bio 113 | heading |