Biology 20 Chemistry Background

Question: What sort of Chemistry background do I need for Bio 20 ?

Glad you asked. We will assume that everyone in the class has taken a high school chemistry course (although I will not assume that you remember very much from it). However, you should be familiar with the following basic concepts:

there are more than 90 naturally occuring chemical elements
each element is represented with a 1 or 2-letter symbol (Cu, O, N, Fe, etc..)
elements combine in fixed proportions to form compounds (H2O, CO2, etc..)
atoms are the smallest units of an element
atoms contain protons (+), electrons (-), and neutrons
protons and neutrons are found in the nucleus of the atom.
electrons are arranged around the nucleus in energy levels or orbits around the nucleus.
each atom has an atomic mass roughly equal to the sum of its protons and neutrons.
elements have different forms, known as isotopes (C14, C13, C12, etc..)
some isotopes (235U, 3H, etc..) are radioactive, meaning that they break down to release particles and energy spontaneously.
chemical bonds may form between atoms to yield molecules.
the molecular mass (or molecular weight) of a compound is the sum of the atomic masses in one molecule of the compound.
There are two important forms of chemical bonds, ionic and covalent.
An ionic bond is formed between atoms that have gained or lost electrons (such atoms are known as ions) (NaCl, MgCl2)
A covalent bond is formed between atoms that share a pair of electrons.
atoms may share one pair of electrons (single bonds), two pairs (double bonds), or three pairs (triple bonds).
Water may dissociate into OH- and H+ ions.
The acidity of water is measured by an index known as pH, which is determined by the hydrogen ion (H+) concentration of a solution. Specifically: pH = -log [H+]
Acidic solutions have low pH values (pH 1-3) , Basic (alkaline) solutions have high pH values (pH 11-13), and pure distilled water has a pH of 7.0.
This basic chemical knowledge will be assumed in Biology 20. Chapter 14 of the textbook includes a review of basic chemistry which may be helpful if you feel uncertain about any of these concepts.

NOTE: This is not the only chemistry that we will use in Bio 20. Additional chemistry will be covered as needed to discuss molecular biology and chemical metabolism.

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