Chapter 7, Problem 13A

Summary Introduction

To fill:

The correct term in the given blank.

Introduction:

A cell is a structural and functional unit of an organism. Every cell is surrounded by a protective covering called plasma membrane. It controls the entry and exit of substances into and out of the cell. Both prokaryotes and eukaryotes have plasma membrane. It helps in maintaining homeostasis.

Answer to Problem 13A

Selective permeability is the property that allows only some substances in and out of a cell.

Explanation of Solution

All types of cells are surrounded by an outer boundary called plasma membrane. It is a thin, flexible boundary between a cell and its outer environment that allows nutrients into the cell and wastes to leave the cell. An important property of plasma membrane is selective permeability, by which a membrane allows some substances to pass through while keeping others out. This property is important to the survival of a cell.