Chapter 6, Problem 6TYU

Summary Introduction

To explain:

Draw and label model of plasma membrane of a cell that is placed in a solution with concentrations of calcium ion and lactose that are greater than those on the inside of the cell, and use arrows to show the relevant gradients and the activity of the following membrane proteins:

1. a pump that exports protons;

2. a calcium channel; and

3. a lactose carrier.

Introduction:

The plasma membrane is composed of a phospholipid bilayer, which is selectively permeable and regulates the entry and exit of the cell. The different solute concentrations outside and inside the cell create a concentration gradient. The solutes move from regions of high concentration to regions of low concentration during concentration gradient.