Agenda

  1. Turn in Lab 2 by the staplers on the North bench.
    1. Needs a name and group number
  2. ~10 min.: Q&A on Lab 2 material
  3. 20 min.: Quiz 2
  4. ~2 hrs.: Lab 3: Enzymes
  5. ~30 min.: Next lab reminders/questions/review

Lab 2 Q&A

What is pH?

Why is pH important?

What stabilizes our body pH?

CO_2+H_2O \rightleftharpoons H_2CO_3 \rightleftharpoons H^+ + HCO_3^-
CO2+H2O⇌H2CO3⇌H++HCO3−CO_2+H_2O \rightleftharpoons H_2CO_3 \rightleftharpoons H^+ + HCO_3^-

Carbonic

anhydrase

Henderson-Hasselbach Equation

6.1 + log(\frac{[HCO_3^-]}{[H_2CO_3]})
6.1+log([HCO3−][H2CO3])6.1 + log(\frac{[HCO_3^-]}{[H_2CO_3]})
6.1 + log(\frac{[HCO_3^-]}{0.03 \frac{mmol}{L\times mmHg} \times PaCO_2})
6.1+log([HCO3−]0.03mmolL×mmHg×PaCO2)6.1 + log(\frac{[HCO_3^-]}{0.03 \frac{mmol}{L\times mmHg} \times PaCO_2})

Quiz 2

Enzymes

Lab 3

Lab Purpose

To allow students to experiment with catalase, a model enzyme, to observe the effect of pH, temperature, substrate and enzyme concentrations on enzymatic function.

Lab objectives

  • Describe how an enzyme works.
  • Given solutions of enzyme and substrate, be able to determine how the rate of enzyme activity is affected by enzyme concentration, substrate concentration, temperature and pH.
  • Write the equation that describes how the enzyme catalase functions.
  • Explain the location and physiological significance of catalase.

Lab Safety

  • Goggles!
  • Closed toed shoes
  • Gloves
  • Adequate coverage from neck to ankles
  • Put your hair up!
  • If you spill acid tell me and I will get you some baking soda.
  • Hydrogen Peroxide
    • DO NOT BOIL!!!
    • There are two concentrations
  • Use litmus paper, not pH meters.

What are we doing?

Lab Hacks

  • Height = how deep the paper sinks, not total depth
  • Cold dH2O = normal dH2O

Core Principles

What is an enzyme?

How does it work?

How do the following affect enzyme function?

  • Enzyme concentration
  • Substrate concentration
    • Saturation point
  • pH
  • Temperature

Catalase Function

2H_2O_2 \rightarrow 2H_2O + O_2
2H2O2→2H2O+O22H_2O_2 \rightarrow 2H_2O + O_2

Catalase

Catalase

  • Where is it found?
    • Peroxisomes, predominantly in the liver.
  • What does it do?
    • Degrades hydrogen peroxide to protect cells from oxidative stress.

Lab 4: Diffusion & Osmosis

  • Read:
    • Stanfield pgs. 101-114
    • Silverthorn 125-135
  • Bring:
    • Goggles
    • Calculator
    • Wear adequate clothing
    • This is a human fluids lab. There will be blood!
  • Lab 3 Reports
Made with Slides.com