AP Biology Lab Tips

FITTING THE LABORATORIES INTO THE SCHEDULE

1. Double periods are recommended.
2. Teach AP first period and have students come early or last period and have students stay after school.
3. Combine some laboratories and do on Saturdays (8/year)
4. Convince nearby college, community college or technical school to run the laboratory program on Saturdays or at special times during vacation periods.
5. Teach material in the laboratory rather than by lecturing and then repeating lectures during laboratory.
6. Develop pre-laboratory sheets to make students think through laboratory procedures prior to the laboratory period.
7. Use video tapes to show laboratory set-ups and techniques.
8. Assign some laboratory investigations (Drosophila, Physiology) as projects to be done on students' own time.
9. Look for logical break points in the laboratories.

CUTTING THE COST OF THE LABORATORY

1. Share materials through a consortium-network with others! Share chemicals and equipment.
2. Use disposable cups, food balances, slide projectors and tupperware electrophoresis equipment if proper equipment not available.
3. If you can only do experiments qualitatively, at least give students data from the prep guide to work with and interpret.
4. Use micro-scale adaptations.

Lab 1. Osmosis and Diffusion

1. Lab Tips
   1. Use liquid laundry starch or soluble packing pellets in place of soluble starch.
   2. Have students tie knots in the dialysis bags instead of using string.
   3. Have each group do each solution in order to minimize class data error.
   4. Do not use Glucose test tape as it will always test positive in the presence of IKI. Use Benedicts solution or test sticks to test for glucose.
   5. Potato cores will be exactly the same length if you cut the potato first and then use the cork borer to make the cylinders. - Or the potato may be cut into strips of approximately the same size if a cork borer is not available.
2. Scheduling Tips
   1. Do dialysis bags on day 1 (let them soak in water for 30 minutes). Make sure you have enough balances to minimize waiting time.
   2. Do potatoes on day 2 (set-up) and data collection for cores on day 3.

Lab 2. Enzymes

1. Lab Tips
   1. Obtain catalase from Sigma. May be stored for years in freezer.
   2. Use bakers yeast culture as catalase source.
   3. Use liver as catalase source.
   4. KMnO4 stains may be cleaned up using H2O2.
   5. Use syringes to save time (and money) in volume measurements.
2. Scheduling Tips
   1. All reactions may be stopped using acid at the end of day 1 and saved for titration on day 2.

Lab 3. Mitosis and Meiosis

1. Lab Tips
   1. Carolina "Pop Beads" work extremely well (1 kit serves whole class).
   2. Use Sordaria lab kit.
   3. Use boiling "pearl" onions from grocery store for root squash. (Onion root squash can be optional). Compare and contrast animal and plant mitosis.
2. Scheduling Tips
   Mitosis and meiosis do not have to be done together but if you do them together:
   1. Do mitosis on day 1
   2. Set up Sordaria crosses on day 2
   3. Use Sordaria demo plate instead of Sordaria kit.
   4. Check spore capsules each morning to determine if they are mature.

Lab 4. Photosynthesis

1. Lab Tips
   1. Use grasses or other outdoor plants for chromatography.
   2. Set up numbered bank of tubes (0-10) using serial dilutions of DPIP if Spec 20 is not available. Students then match their tubes to color standards in tube bank.
   3. Place spinach in light prior to experiment to activate photosystems.
   4. Mix DPIP immediately prior to lab.
   5. Borrow Spec 20's from other school or local college.
2. Scheduling Tips
   1. If Spec 20's are in short supply, split class in half and have one group do chromatography while the other group does spectrophotometry.

Lab 5. Cell Respiration

1. Lab Tips
   1. Use fresh pea seeds.
   2. Placing wet, non-germinated peas in vials seems to cause problems with data. To avoid wetting dry peas, determine the mass, volume and hence density of 100 dry seeds (D=M/V). Throw these peas away and then use 25 new, truly dry peas for vial (V=M/D).
   3. Use Teflon plumbing tape wrapped around pipettes which are inserted in stoppers. Silicon sealant works but can break down.
   4. Make sure that you have 10% extra vials (some may leak).
   5. Use aluminum roasting pans as water baths.
   6. Any bean seed may be used.
2. Scheduling Tips
   1. This is a long lab. It may have to be run after school or extended into lunch, etc.
   2. All vials may be set up on day 1 and stored upright in refrigerator overnight. Experiment may then be run on day 2.

Lab 6. Molecular Biology

1. Lab Tips
   1. Use Carolina Kits for this lab (Restriction Digest and Transformation).
   2. Borrow electrophoresis equipment.
   3. Do demo of electrophoresis.
   4. Do simulation of electrophoresis.
   5. Use "Paper Plasmid" lab from "The Science Teacher" (April, 1987).
   6. Use predigested DNA for electrophoresis.
2. Scheduling Tips
   1. Do transformation on day 1. Read plates on day 2.
   2. Do restriction digest on day 2 or 3 and store tubes in freezer after digest is complete.
   3. Load gels on day 3 or 4.
   4. Run gels overnight or all day at very low voltage (see lab kit manual for exact times).

Lab 7. Genetics

1. Lab Tips
   1. Use Carolina Kit and/or Carolina F1 flies.
   2. Use "Wisconsin Fast Plants" if you don't like flies.
   3. Use CO2 from Alka Seltzer to knock out flies initially, then place on "ice stage."
   4. Have student lab T.A. maintain fly cultures.
2. Scheduling Tips
   1. Send flies, vials and magnifiers home with students so they can complete counts outside of class.

Lab 8. Population Genetics and Evolution

1. Lab Tips
   1. Invite other students to lab in order to increase population size.

Lab 9. Transpiration

1. Lab Tips
   1. Use house plant if bush beans are not available.
   2. Cut plant stems and insert stem into tubing while stem is submerged in a pan of water. This prevents air gaps from forming in xylem vessels.
   3. Buy disposable glass pipettes (and reuse).
   4. Preparing stem cross section can be optional.
2. Scheduling Tips
   1. Use prepared slides from step cross sections.

Lab 10. Physiology of Circulatory System

1. Lab Tips
   1. Insist on silence during lab so accurate measurements can be made.
   2. Borrow equipment from hospitals or doctors offices.
   3. Ask for donations of old equipment.
   4. Set up several different temperature baths (ahead of time) and have students rotate Daphina to each water bath.
2. Scheduling Tips
   1. Do physiology measurements on day 1 and Q10 measurements on day 2.

Lab 11. Habitat Selection

1. Lab Tips
   1. Cover control tubes with black tape instead of using cloth.
   2. Purchase screens from building supply store.
   3. Grow brine shrimp ahead of time so that all individuals are of uniform age.
   4. Use zip lock bags to hold water solutions.
   5. Suspend samples for counting in 1 ml or 5 ml pipettes for easier counting.
   6. Drain 1 ml samples onto paper towel for counting (watch for dead shrimp).
2. Scheduling Tips
   1. Run lab on day 1. Store 1 ml samples of shrimp in refrigerator overnight and perform counts on next day (this may result in shrimp mortality).

Alternate Lab 11

Use the same equipment as described in lab manual. Instead of brine shrimp, use live adult Drosophila as the test organism, simply empty a uniform number of sleeping flies (20-50) into the dry tygon tubing. For experimental conditions, the following variables may be tested:

1. Light intensity. Simply use the same screens and procedure as in the lab directions.
2. Temperature. Here again, use the same protocol as is currently in the lab.
3. Light color. Use different colors of cellophane gels (obtain from drama department) and apply these in various combinations to each quadrant section of tygon tube. Expose entire tube to bright room light or spot light. Flies will then migrate to preferred color region.
4. At the end of 10-20 minutes, clamps can be applied to tube and counts can be done directly in tygon tubing.

Lab 12. Dissolved Oxygen Lab

1. Lab Tips
   1. Use LaMotte test kits and extra BOD bottles instead of lab protocol.
   2. Once samples are fixed, they can be stored in refrigerator for titration later.
   3. Expand study to include natural water bodies (lakes, ponds, etc.). Have students conduct a seasonal study of these water bodies.
2. Scheduling Tips
   1. Set up lab on day 1. Fix samples on day 2. Titrate samples on day 3.