Difference Between Active and Passive Transport

Active and Passive transport system is present in every phospholipid bilayer of the cell wall, which performs transportation of desired molecules such as nutrients, oxygen, water, and other molecules inside the cells and removal of waste products outside of the cell. Active transport requires ATP to transport molecules from lower concentrations to higher concentrations, while passive transport does not require ATP as it transports molecules from high concentration to low concentration gradient.

In this article, we will explore the key difference between Active and Passive Transport along with the types.

What is Active transport?

It is a type of transport system which requires energy to transport large molecules like protein, sugar etc. from lower concentration to higher concentration. The energy is required in the form of ATP i.e., adenosine triphosphate.

Types of Active Transport

There are 2 types of Active transport:

Primary Active Transport

In the primary active transport, transmembrane proteins help detect the molecule that has to be carried. These molecules are then pumped to the desired location utilizing ATP, a chemical energy.

For instance, primary active transport mechanism aids in the transportation of the Na/K via sodium/potassium pump. During this process, the cell’s transmembrane proteins detect the need for extracellular fluid and pump the necessary molecules using ATP. Consequently, two K ions are transported into the cells and the three Na ions are pump out of the cell.

Secondary Active Transport

Secondary active transport is processed by porin proteins present in the transmembrane. In this type of transport electromagnetic current forms a channel though which transportation of molecule occur. Secondary active transport consists of two other transport system which is known as Co-Transporters.

Co-transporters are categorized into two types:

• Symporters: Symporters works, when solute and ions travel in the same direction.
• Antiporters: Antiporters work, when ions and solute flow in the reverse direction. For example, sodium/calcium exchanger.

What is Passive Transport?

It is a transport system which does not required any energy to transport molecule across the membrane of cell from a high-concentration to a low-concentration gradient. A concentration gradient is not necessary for passive transport, in contrast to active transport. Passive transport uses heat energy instead of ATP for transportation of molecules.

Types of Passive Transport

There are 3 types of Passive transport:

Osmosis

The transfer of water molecules from an area of higher concentration to a region of lower concentration over a semipermeable membrane is known as osmosis.

Osmosis is of two types

• Exo-osmosis: Exo-osmosis is the process in which water leaves a cell when it is submerged in a hypertonic solution. The cell contracts and becomes more voluminous as a result.
• Endo-osmosis: When a cell is submerged in a hypotonic solution, water enters the cell by osmosis. This process is known as endosmosis.

Simple Diffusion

Transportation of molecules via simple diffusion from a higher concentration to a lower concentration until equilibrium is reached. In plants, basic diffusion facilitates the exchange of CO₂ and O₂ and it does not require energy for transportation.

There is one more type of simple diffusion that is known as imbibition: Imbibition is a process of diffusion in which liquid like water get absorbed in to solid cell like plant seed thus increasing the volume of seed.

Facilitated Diffusion

It is referred to as facilitated diffusion when lipid insoluble molecules are transferred across the membrane with the assistance of certain proteins (Channel proteins, gated channel proteins and carrier proteins) and it does not required ATP.

Difference Between Active and Passive Transport

Below are the some listed difference between active and passive transport system

Properties	Active Transport	Passive Transport
Energy	It requires ATP to perform transport	It does not requires ATP to perform function
Transport gradient	In this transport occur from lower concentration to higher concentration	Transport occurs from higher gradient to lower gradient
Molecules	It usually transports large molecules like sugar, proteins, ions etc.	It transports soluble molecules like O2 , CO2, hormones etc.
Direction	Unidirectional	Bidirectional
Selective	It is highly selective process	It is partially selective process
Influence of temperature	It is very sensitive to temperature	It is not temperature sensitive process
Inhibitors	It can be inhibited by metabolic inhibitors	It can not be inhibited by metabolic inhibitors
Types	Endocytosis, Exocytosis and Na/K pump	Osmosis, simple diffusion, facilitated diffusion
Speed rate	It is a fast or rapid process of transport	It is a slow process of transport in contrast to active transport
Oxygen dependent	Oxygen molecule is required to continue the process	Does not require oxygen molecule to continue the process

Conclusion – Difference Between Active and Passive Transport

Active transport need energy, while passive transport do not need energy for transportation of molecules. In active transport molecules transported against the gradient while in passive transport molecules move with the gradient. Active transport are of two types primary and secondary transport wherein secondary transport consists of cotransporters i.e. antiport and symport. Passive transport is of three types osmosis (endo-osmosis and exo-osmosis), facilitated diffusion and simple diffusion (imbibition). These all transports help in transportation of desired molecules inside the cell and removal of waste product from inside to outside of the cell.

FAQs on Active and Passive transport

What is the Difference Between Active Transport and Transportation?

Active transport necessitates energy to move substances against their concentration gradient, whereas passive transport requires no cellular energy and moves substances along their concentration gradient.

What is the Importance of Active and Passive Transport?

Active transport is vital for cell survival, enabling the movement of substances against concentration gradients, from low to high concentration. Passive transport is essential for proper plant and animal functioning, facilitating the diffusion of gases plant cells.

What are Two 2 Types of Active Transport?

Active transport can be categorized as either primary or secondary. Primary active transport relies on chemical energy, specifically ATP. In contrast, secondary active transport utilizes potential energy, often derived from an electrochemical potential difference.

What are the 3 Types of Passive Transport?

Passive transport comprises three fundamental mechanisms: osmosis (endo-osmosis and exo-osmosis), facilitated diffusion and simple diffusion (imbibition).

Which is the Best Example of Active Transport?

The sodium-potassium pump exemplifies active transport on the cell membrane, expelling 3 sodium ions outside the cell and admitting 2 potassium ions inside per ATP.

What is the Role of ATP in Active Transport?

ATP plays a vital role in actively transporting molecules such as proteins and lipids in and out of the cell. The hydrolysis of ATP provides the energy needed for this transport against concentration gradients.

What are the Two Examples of Active and Passive Transport?

Active transport include the Na/K Pump (moving Na out and K into the cell) and the Proton Pump in the stomach (transporting H⁺ ion for digestion).