Featured in PASCO’s Biology through Inquiry Teacher Guide

Biology through Inquiry Teacher Guide

(PS-2870C)

Features 25 inquiry based labs covering the fundamental concepts of cell biology, ecology and physiology.

Membrane Permeability

Lab Summary

Use a pH sensor to explore the permeability of a cell-like membrane to hydrogen (H+) and hydroxide (OH-) ions. Observe that not all materials are able to pass through the membrane.

Theory

This activity is designed to provide students with an understanding of semi-permeable membranes. Students:

  • Explore the permeability of a cell-like membrane to hydrogen (H+) and hydroxide (OH–) ions.
  • Observe that not all materials are able to pass through the membrane.

Method

Students gain experience conducting the following procedures:

  • Measuring the change in pH in water when a dialysis tubing bag (representing a cell membrane) filled with either a strong acid or strong base is immersed in the water.
  • Calculating the rate of change of pH per minute.
  • Observing whether starch can permeate the membrane.

Sensors / Equipment Used:

PASPORT pH Sensor

(PS-2102)

Has a wide measurement range of 0 to 14 pH. Has a resolution of 0.01 pH. For use with PASPORT Interfaces.

Base and Support Rod

(ME-9355)

The Large Base and Support Rod includes built-in leveling screws and an aluminum rod that is 12.7 mm (1/2 in.) in diameter and 45 cm long.

Magnetic Stirrer

(SE-7700)

A "must-have" piece of lab equipment when doing titration experiments.

Buret Clamp

(SE-9446)

The V-shaped, plastic-coated jaws will gently hold a buret and lock at any angle.

Materials Used:

0.1 M hydrochloric acid (HCL), 15 mL

0.1 M sodium hydroxide (NaOH), 15 mL

Beaker, 250-mL

Dialysis Tubing, 15-cm length

Lugol's Iodine

Starch solution

Distilled Water

Binder Clip

String

 

Your Bundle Options:

Option 1:

Biology Starter Sensor Bundle

(PS-2920)

A sensor bundle specifically designed to get you started using probeware in your biology lab. Also: perform 10 of the 24 Lab Activities from Biology with Inquiry.

Option 2:

Biology Standard Sensor Bundle

(PS-2925A)

The Biology Standard Sensor Bundle includes a photosynthesis tank and the sensors required to perform 19 of the 24 Lab Activities in the Biology through Inquiry manual.

Interface Required

This experiment may require software and an interface for data collection.