Enzyme Lab Notebook Format

• 1) Title/Date• 2) Pre-lab (Key Concepts, Equations, Materials)• 3) Purposes (2-3)• 4) Personal Account• 5) Discussion– only 1 question (on bottom of pg 3 of

packet)• 6) Conclusion

Lab 2: Enzyme catalysis

Guaiacol + 2H2O2 tetraguaiacol + 8H2O (colorless) (brownish orange)

Enzyme = peroxidase

Substrate = peroxide (H2O2)

How will we measure enzyme function? - Color change using a spectrophotometer

peroxidase

How does a spectrophotometer work?

Take home points1.Light at a specific wavelength is sent through a liquid sample2.Light passing through the sample is detected on the other side3.To measure this accurately, we must calibrate (blank) the spec.4.Calibrating the spec sets the range & “tells” the spec:

- what 0% light is (darkness)- what 100% light is (all light passing through)

-For our experiment we will see how the amount of light passing through changes as the reaction proceeds.

Tube #1(blank)

Tube #2 Tube #3

Guaiacol 0.1 mL (2 drops)

0.1 mL (2 drops)

---

H2O2 --- 0.2 mL (4 drops)

---

Turnip extract(peroxidase)

1.0 mL (20 drops)

--- 1.0 mL (20 drops)

dH2O 5.2 mL 5.0 mL ---

1. Set wavelength to 500 nm2. With the chamber empty, use left knob to adjust to 0% T3. Insert tube #1 (blank) into spec & use right knob to adjust to 100% T4. Pour #2 into #3 & begin timing immediately!!5. Invert 2X quickly & place into spec6. Record %T every 10 sec for 120 secs7. From page 3, choose your experiment for tomorrow

• This weekend:-Work on Enzyme Lab Entry-Work on Pocket Mouse Signaling Packet

-BOTH due on TUESDAY!

• Enzyme Lab Overview– Only hypothesis/procedure/data from FRIDAY needs to

be included.– Slope calculation for EACH of your four lines

• ΔY / ΔX (Units = Y units / X units)

– Discussion section (section #5) is only ONE question!

• Please put your LAB NOTEBOOK in the blue crate.

• Please put your MOUSE SIGNALING PACKET in the appropriate homework file.– Make sure your name is on the packet!

• Unit 4 Test Review Session (Q&A)– TOMORROW (Wednesday) at 7:00am

– TEST REMINDERS:• 1) Don’t forget about your “Potential FRQ” sheet…you

got this on Tuesday, Nov. 24th • 2) Don’t forget about your “Math Practice” sheet…you

got this in mid-November. Answers are posted online under Ch. 7 PPT notes

• ENZYME LAB OVERVIEW:• #1: Varied Concentration of Enzyme (peroxidase)

– More enzyme = faster reaction• #2: Varied Concentration of Substrate (H2O2)

– Less substrate = slower reaction– More substrate = faster reaction– Even more substrate = slower reaction

• #3: Varied Environmental Temperature– Body temp = fastest rate

• #4: Varied Environmental pH– pH 8 = slow reaction; pH 5 = slow reaction

• #5: Varied Exposure Times to Boiling Water– Reaction stops completely when enzyme boiled