Page 6 “Two years earlier, most scientists had believed…” Change to “Many scientists believed…”

“But in 1922… Change to “But that year…”

The revised lines should read: “Many scientists believed that the entire universe consisted of the Milky Way and a few other galaxies. That was it, because that was all they could see. But that year at California’s Mount Wilson Observatory, Edwin Hubble shocked them.”

Page 32 “a million times smaller than a grain of sand” Change to “trillions times smaller than a grain of sand””

Page 46 He knew that carbon is the sixth most common element in the universe.” Change “sixth” to “fourth”

Page 87  “roughly 99 percent“ Change to “roughly 98 percent”

Page 98  “NH4” Change to “NH3”

Page 157 “Using radioactive oxygen-18” Change to “Using the isotope oxygen-18”

Page  164 “NAHDP” Change to “NADPH”

Page 256  “One had an exterior rough coating…” Delete the word “exterior”

“The other had a smooth coating…“ Change “smooth” to “slimy”

The revised lines should read:  “One had a rough exterior and was harmless when injected into mice. The other had a slimy coating and was lethal.

Page 257 “It was 0.01 percent protein. The other 99.99 percent …” Change to: “It was less than one percent protein. The other 99 percent….”

Page 295  “….is created by molecules of negatively charged sodium and positively charged potassium.” Change to  “….is created by positively charged sodium and potassium ions.”

Page 306  “seventy octillion atoms” Change to “seven octillion atoms”