absolute zero alternating current artesian well big bang black hole Brownian motion Cambrian Explosion carbon sequestration Fibonacci sequence fundamental force game theory imaginary number junk DNA KT boundary Kuiper belt logic gate Munchausen syndrome nosocomial infection piezoelectric effect protein folding quantum mechanics radiometric dating rain shadow REM sleep solar wind tidal force time dilation Universal Time wave function agoraphobia alga algorithm allele amygdala anaphylaxis angiogenesis apoptosis archaeon ATP bandwidth Beringia capacitor centripetal force chemosynthesis cognitive dissonance complementarity cryptography cyanobacterium cyclone dendrochronology echolocation endorphin estivation eutrophication fission genome gluon heliocentrism histone hominin hypha interferon ischemia isomer krill kwashiorkor magnetosphere megabyte melanoma mitochondrion monotreme monsoon nanotube Neanderthal obligate orbital pahoehoe Pavlovian phenotype pheromone photoelectric photon placebo prion prophylaxis protolanguage refraction retrovirus roentgenium sex sociobiology superposition telomere teratogen theory urea vestigial xerophyte yolk zero