Format of test: multiple choice (about 25 to 30), grid-in math calculations (2-3), 2 short answer, no long free response
question
Scoring: 1 point each for multiple choice and grid-in; 4 points each for short answer
This is our first test with short answer questions. On the AP Biology exam these are expected to take 5-6 minutes, you
would usually answer in a single paragraph (unlike the longer FRQs), and each question has a point value of 3-4 points.
Topic: Multiple choice – chapters 2-4, 5.1 and 5.2; grid in temperature conversions, molarity, pH (my calculators will be
used), temperature formulas will be provided; short answer topics 1) concerns how the structure of water is related to
its emergent properties 2) concerns how the structure of the carbon atom is related to the great diversity of organic
compounds
The figure below explains how to fill in your answers on math questions. Although the AP Biology exam does not ask
students to show their work, I do. If you are not sure how to grid-in your answer during the test, just ask for help.
Chapter 2
1. Distinguish between elements and compounds. What are the 6 most common elements in living things?
2. Name the subatomic particles and give their charge, location, and mass. Atoms are mostly empty space! Most
of the mass is located in the nucleus.
3. If given the atomic number and mass number, you should be able to describe the structure of the atom. You
should be able to interpret a Bohr model diagram. The number of protons identify the element and the
organization of the electrons in the valence shell determine the element’s chemical behavior.
4. Define and give examples of isotopes. What is a radioactive isotope and how are they used in biology and
medicine?
5. How is the potential energy of an electron related to its position in an energy level (electron shell)? Remember
that the energy levels represent the average distance of the electron from the nucleus not its location within the
electron cloud.
6. When you look at the number of electrons in a valence shell, you should be able to predict whether the atom is
chemically active or inert. Recall that elements that have the same number of electrons in their valence shell
have similar chemical properties.
7. The actual 3-dimensional space in which an electron is found 90% of the time is called an orbital. Each orbital
can hold only 2 electrons. Atoms with unpaired electrons in their valence shell orbitals form bonds in a way that
completes their valence shells. You do not need to distinguish between the different types of orbitals.
8. You are responsible for distinguishing between 4 types of bonds: covalent (polar and nonpolar), ionic, hydrogen
bonds, and van der Waals interactions. You have a hand out that compares them. Many of you need to review
the concept of electronegativity on page 39. Electronegativity is a measure of an atom’s attraction for electrons
in a chemical bond. If there is little to no difference between two atoms, the bond is a non-polar covalent bond.
A small electronegativity difference leads to a polar covalent bond. A large electronegativity difference leads to
an ionic bond.
9. How is the shape of a molecule important to its function in the cell?
10. You should be able to read and interpret a chemical reaction. This includes determining whether or not an
equation is balanced. You should be able to read and interpret a molecular formula, an electron distribution
diagram, a Lewis dot structure, a structural formula, a ball and stick model, and a space-filling model.
Chapter 3
1. Water’s unusual properties are due to its polarity and hydrogen bonding. Make sure you thoroughly understand
this. Concept 3.1 and Figure 3.2 are very helpful. You may need to review parts of Chapter 2: electronegativity
and polar covalent bond, page 39, and hydrogen bonds, pages 40-41.
2. Discuss the 4 emergent properties of water: attraction between water molecules and between water molecules
and other substances (cohesion, adhesion, capillarity, surface tension), moderation of temperature (high specific
heat, evaporative cooling), expands when it freezes (ice floats), and excellent solvent. Practice explaining how
these behaviors are related to the structure of water. Give examples which illustrate how each of these
properties important to life on earth.
3. Review the concepts of heat and temperature. Be prepared to convert between Celsius and Fahrenheit
temperature scales – for grid-in questions. What is the difference between a calorie and a Calorie?
4. Why are some substances hydrophilic and some hydrophobic?
5. Distinguish between the terms solution, solute, and solvent. How do you make solutions with specific
concentrations using the concept of the mole? Grid-in questions will ask you to calculate solute required for
solutions of a specific molarity. Mass numbers will be given in the problem.
6. What ions are involved in making a solution an acid or a base? What makes a substance an acid or a base? How
is this related to the ionization (dissociation) of water? Can you interpret the pH scale? Given two pH numbers
can you compare their hydrogen ion concentrations (hint: powers of 10)? Given pH numbers you should be
able to give the pOH and the concentration of each ion (written within brackets). These calculations may be
included in a grid in question.
7. What is a buffer and why do cells need them? Using the carbonic acid-bicarbonate buffering system in human
blood, explain how buffers work.
8. What is the pH of normal precipitation? What is acid precipitation and how are human activities involved in its
production? We did not discuss the acidification of ocean waters due to excess CO2 – but you should read
through this section if you have not already done so.
Chapter 4
1. Define organic compound.
2. No questions at this time on Concept 4.1.
3. Describe how the structure of the carbon atom makes the diversity of organic compounds possible: valence of 4,
number of covalent bonds, variations in carbon skeleton, isomers. Figures 4.3, 4.4, 4.5, and 4.7 are very helpful.
4. Define isomer and distinguish between structural isomer, geometric isomers (cis and trans), and enantiomers.
Locate the chiral or asymmetric carbon of an enantiomer. What is the significance of enantiomers in the
pharmaceutical industry?
5. Recognize the 7 common functional groups by name and structure, identify their properties (polar, nonpolar,
acid, base, etc.). Remember the examples in Figure 4.10 are so you can practice recognizing a functional group –
you don’t need to memorize them or their names.
Chapter 5
1. What are the four classes of macromolecules?
2. How are polymers synthesized from monomers? How are polymers broken down into monomers? What is the
role of enzymes in these chemical reactions? What bond is made and broken between the monomers during
these reactions? If the polymer is 10 monomers long, how many water molecules were produced when it was
built by the cell (or how many water molecules will be required when the polymer is broken down into
monomers)? Figure 5.2 is very helpful.
3. What is the role of carbohydrates in cells?
4. Distinguish between and give examples of monosaccharides (glucose, fructose, galactose), disaccharides
(sucrose, lactose, maltose), and polysaccharides (starch, glycogen, cellulose, chitin). What is the role of these
molecules in cells? How are these molecules assembled and broken down by cells?
5. What elements are found in all carbohydrates? What is the ratio of H to O? What functional groups will help
you determine whether the structural formula you are looking at is a carbohydrate?
6. Figure 5.3 will help you understand the diversity of structures in monosaccharides: position of the carbonyl
group (aldose or ketose) and length of the chain (3 to 7 C). You can practice recognizing isomers too. Which
molecules are structural isomers of each other? Which are enantiomers? You must recognize these structural
formulas as 1) organic compounds 2) carbohydrates (look at functional groups) 3) monosaccharides (no C-chain
longer than 7). You DO NOT HAVE to name them or draw them or memorize their formulas. But remembering
common formulas is very helpful! C6H12O6 is glucose, fructose, or galactose. C12H22O11 is sucrose, lactose, or
maltose. HMMM, these must be isomers.
7. Figure 5.4 helps you understand how the linear form of a monosaccharide folds up into a ring form. The ring
form is most common in cells. Note that as the ring closes 2 functional groups are involved: hydroxyl and
aldehyde. An oxygen is “trapped” in the ring - the O in the ring and the hydroxyl groups will help you identify
ring form carbohydrates.
8. Figure 5.5 helps you understand the formation of disaccharides from monosaccharides. Reverse the reaction
arrow and you will understand the hydrolysis of a disaccharide into monosaccharides. So that’s what it looks
like when I digest table sugar! Be sure you can identify the glycosidic linkage between monomers. What kind of
chemical bond is that? If you are given the molecular formula of 2 monosaccharides, can you write the formula
for the disaccharide they would produce? You must recognize the structural formulas for disaccharides as 1)
organic compounds 2) carbohydrates (look at functional groups) 3) disaccharides (two rings). You DO NOT HAVE
to name them or draw them or memorize their formulas.
9. The 2 storage polysaccharides you need to know about are starch and glycogen. Plants and animals “bank” their
glucose by storing them in these polymers. How do starch and glycogen polymers differ in structure? Where is
each produced and stored?
10. The 2 structural polysaccharides you need to know about are cellulose (plant cell walls) and chitin (arthropod
exoskeletons and fungal cell walls).
11. Starch and cellulose are both polymers of glucose and they have different functions. Explain why their 3dimensional shapes are different. Animals typically have no problem digesting starch to glucose but they cannot
break down cellulose. Explain. What organisms can break the glycosidic linkages of cellulose?
12. You must recognize the structural formulas for polysaccharides as 1) organic compounds 2) carbohydrates (look
at functional groups) 3) polysaccharides (many rings). You DO NOT HAVE to name them or draw them.