Chapter 6, Problem 1PL

Which of the following membrane movements is not a passive process?

1. osmosis
2. diffusion
3. active transport
4. filtration

Summary Introduction

Introduction:

Passive transportation is a method in which the movement of the cellular substances takes place from one cell to another. Energy is not required in the transport of molecules.

Answer to Problem 1PL

Correct answer:

The correct answer is option (c) active transport.

Explanation of Solution

Explanation/justification for the correct answer:

Option (c) active transport. Active transportation is the passage of molecules from cell to cell. It requires energy for the process of transport as the movement is initiated against the concentration gradient. So, the correct answer is option (c).

Explanation for incorrect answer:

Option (a) osmosis. Osmosis is a process of movement of water molecules from low concentration to a high concentration. It requires no energy for the process of transport. So, this is an incorrect option.

Option (b) diffusion. Diffusion is a process of movement of molecules, ions, and atoms from high concentration to low concentration. It occurs in the absence of energy. So, this is an incorrect option.

Option (d) filtration. Filtration is a process of movement of solute or fluid against the gradient. The process of filtration occurs by applying the pressure, which can result in the movement of the molecules against the gradient. It does not require energy and filter across the semi-permeable membrane. So, this is an incorrect option.