Question

Active and passive transports across cell membrane differ in
A. Passive transport is non-selective.
B. Passive transport is along the concentration gradient while active transport is due to metabolic energy.
C. Active transport is more rapid.
D. Passive transport is confined to anions while active transport is confined to cations.

Answer 1

Hint: Active transport and passive transport in both the processes movement of biomolecules take place across the cell membrane from a region to another region. We will see the differences between both types of transports and then conclude the answer of the given question.

Complete Answer:

Features	Active transport	Passive transport
Definition	In this type of transport the movement of molecules occurs across the cell membrane using ATP.	In this type of transport the movement of molecules occurs across the cell membrane without the expenditure of energy.
Concentration gradient	Here the molecules move from the region of lower concentration to a region of higher concentration.	Here the molecules move from a region of higher concentration to a region of lower concentration.
Energy requirement	Energy is required in the form of ATP.	No energy is required.
Direction of movement	In this type of transport the molecules move upward.	Here the molecules move downward.
Carrier proteins or pumps	Carrier proteins or pumps required.	No requirement of carrier proteins or pumps.
Efficiency of process	It is a rapid process.	It is a slow process.
Direction	It only occurs in one direction.	It is bidirectional.
Selectivity	It is a highly selective process.	It is non- selective.
Effect of temperature	Affected by temperature.	Not affected by temperature.

So, option A is the correct answer.

Note: In active transport the molecules move across the cell membrane against the concentration gradient i.e. from a region of lower concentration to a region of higher concentration. Ex: Sodium / Potassium channel, calcium channel.