Goals:

to introduce students to one of the basic physiologic properties of cells - the cell's electrical potential;

to demonstrate how the resting membrane potential of a cell gives rise to the action potential- the basic method of cell signaling, muscle contraction and cell secretion; and

to show through a real-life example how basic cell physiology influences the heartbeat and accounts for sudden death in Long QT syndrome.

Objectives:

Students will:

discuss a previously read excerpt from Kara Mia, the story of Kara Anglim, a 14-year-old who suffered a cardiac arrest during track practice in 1995 due to an inherited problem with her heartbeat called Long QT syndrome;

use scientific calculators and a computer model of the cell membrane both to confirm the theoretic value of the resting membrane potential for a model cell and to test this theoretic value in a simulated patch-clamp experiment;

discuss the action potential and view patch-clamp experiments demonstrating the action potential;

discuss ion channels, the molecular basis of the action potential; and

learn how a specific ion channel defect results in one form of Long QT syndrome.

Maine Performance Indicators: This lab aligns with the following Maine performance indicators: C1,2, and 4, D1, H7, I4, J1 and 2, K4 and 5, L1,4,5,7, and 8, M4, and is allied with Advanced Placement Biology Lab #10.

Target audience: Advanced Placement Biology students with knowledge of cell and heart anatomy

Length of presentation: 1.5 hours

Required materials: scientific calculators. All other materials, including laptop computers with the patch-clamp experiment simulation, are supplied by ScienceWorks for ME.

Important background concepts for this unit:

Biology

1. Cell membrane structure and function
2. Constituents of the cytosol
3. Ion channels
4. The Central Dogma: DNA produces RNA produces protein
5. Meaning of DNA "mutation"

Chemistry

1. Cations and anions
2. The importance of charge in making solutions "conductive"
3. Principle of diffusion

Physics

1. Meaning of a "constant"
2. The gas constant, (R) descriptive knowledge
3. Faraday's constant, (F) descriptive knowledge
4. A basic understanding of the concepts of Work and Energy
5. Concepts of electricity and conceptual understanding of voltage, current, and the equation: V= I x R

Math

1. How to take a log of a number
2. How to graph