[BIOL 1102] - Midterm Exam Guide - Comprehensive Notes for the exam (19 pages long!)
Document Summary
Big bang: about 13-14 billion years ago. Within three minutes after the big bang: protons and neutrons combine to form the first atomic nuclei, protons: positive charge, part of nucleus, neutrons: no charge, part of nucleus. What were the first nuclei to form: the four lightest elements: hydrogen, helium, lithium, beryllium. About 300,000 years after the big bang: electrons now join atomic nuclei to form atoms, electrons: negative charge, in orbit around nucleus. What is hydrogen made of: 1 proton, 1 electron. What is helium made from: 2 protons, 2 neutrons, 2 electrons. What is the most abundant element in the sun and universe: hydrogen (about 90%) One billion years after the big bang: hydrogen clouds are clumping together to form galaxies and stars. Turning hydrogen into helium through nuclear fusion. Where are carbon, nitrogen, and oxygen formed: from fusing helium atoms inside bigger stars called red giants.
