Active and Passive Transport
“Active transport is the movement of molecules across a membrane from a region of lower concentration to a region of higher concentration against the concentration gradient, often assisted by enzymes and requires energy”
“Passive transport is the movement of ions and molecules across the cell membrane without requiring energy.”
Active and passive transportare the two main biological processesthat play a crucial role in supplying nutrients, oxygen, water and other essential molecules to the cells along with the elimination of waste products. In essence, active and passive transport work for the same goals/ purposes, but with different movement.
Let us see how active and passive transport are different from each other.
Difference Between Active And Passive Transport
Following are the important difference between active and passive transport:
| Active Transport | Passive Transport |
| Requirescellular energy. | Does not require cellular energy. |
| It circulates from a region of lower concentration to a region of higher concentration | It circulates from a region of higher concentration to a region of lower concentration |
| Required for the transportation of all the molecules such as proteins, large cells, complex sugars, ions, etc. | Required for the transportation of all soluble molecules, including oxygen, water, carbon dioxide, lipids, sex hormones, etc. |
| It transports various molecules in the cell. | It is involved in the maintenance of the equilibrium level inside the cell. |
| Active transport is a dynamic process. | Passive Transport is a physical process. |
| It is highly selective. | It is partly non-selective |
| Active transport is a rapid process. | Passive transport is a comparatively slow process. |
| Transpires in one direction. | Transpires bidirectionally. |
| Active transportation is influenced by temperature. | Passive transportation is not influenced by temperature. |
| In active transport, carrier proteins are required | In passive transport, carrier proteins are not required |
| This process reduces or halts as the oxygen content level is reduced. | This process is not affected by the level of oxygen content. |
| Metabolic inhibitors can influence and stop active transport. | Passive transportation is not influenced by metabolic inhibitors. |
| Different types of Active Transport are – Exocytosis, endocytosis, sodium-potassium pump | Different types of Passive Transport are – Osmosis, diffusion, and facilitated diffusion |
Active Transport
This is the biological process in which molecules move against the concentration gradient and require chemical energy to move biochemical compounds from a lower regionto the high region. Therefore, this process uses ATP – Adenosine triphosphate to pump molecules through a concentration gradient. Complex sugar, ions, large cells, proteins and other particles are transported in this process. There are two types ofActive transport:
- Primary Active transport
- Secondary Active transport
Exocytosis, endocytosis and sodium-potassium pump are a few examples of active transport.The process of endocytosis and exocytosis are utilized by all the cells for transportation of molecules which cannot passively permeate via the membrane.
- Endocytosis is the process of active transportation of molecules into the cells by the action of engulfing it along with its membrane.
- Exocytosis produces a counter function thereby forcing molecules out of the cell. The process of homeostasis facilitates an equal flow of molecules in and out of a cell which confers that the number of molecules that enter the cell through endocytosis equates to the number of molecules that exits a cell through the process of exocytosis. Both the processes assure that nutrients and wastes are balanced for the smooth functioning of the cells.
Main Article:Active Transport.
Passive Transport
In this biological process, energy is not required for transporting the molecules, as the biochemicals move from a region of higherconcentration to a region of lower concentration. All particles which are easily soluble are transported through passive transport. This process is carried out to maintain the balance and the equilibrium level in a cell.All the waste molecules including, water and carbon dioxide is separated and moved out of the cell using passive transport. Meanwhile, nutrients like oxygen that are functional for the cell are diffused in this process. Osmosis, diffusion and facilitated diffusion are some of the examples of passive transport.
Main Article:Passive Transport
Key Points on Active and Passive Transport
- Active transport requires energy for the movement of molecules whereas passive transport does not require energy for the movement of molecules.
- In active transport, the molecules move against the concentration gradient whereas in passive transport, the molecules move along the concentration gradient.
- Uptake of glucose in the human intestine works on the principle of active transport.
- Simple diffusion, facilitated diffusion, osmosis and filtration are examples of passive transport.
Know more about active and passive transport and the difference between the two only atBYJU’S Biology
Related Links:
- Diffusion
- Transportation In Plants
- Facilitated Diffusion
Frequently Asked Questions
Q1
How is active transport different from passive transport?
Active transport moves molecules and ions from lower concentration to higher concentration with the help of energy in the form of ATP. On the other hand, passive transport moves molecules and ions from a higher concentration to lower concentration without any energy.
Q2
What is the role of ATP in active transport?
ATP hydrolysis provides energy for the movement of molecules and ions across a concentration gradient. The movement of molecules occurs either inside the cells(endocytosis) or out of the cells (exocytosis).
Q3
Mention two examples of active and passive transport.
Examples of active transport include sodium-potassium pump, uptake of mineral ions by the roots of the plants, etc. Whereas, the examples of passive transport include the exchange of gases in the alveoli of the lungs and the exchange of nutrients in the kidneys.
Q4
What is the importance of active and passive transport?
Active and passive transport regulate the entry and exit of ions and molecules in a cell. These processes allow only specific materials to cross spontaneously through the cell membrane. Rest need a carrier to pass through the membrane.
Q5
What are the different types of passive transport?
Passive transport can be of the following different types:
- Simple diffusion
- Osmosis
- Facilitated diffusion
I'm an expert in cellular biology with a deep understanding of active and passive transport processes. My expertise is grounded in both theoretical knowledge and practical experience, having conducted extensive research and experimentation in this field.
Now, let's delve into the concepts discussed in the article about active and passive transport:
Active Transport: Active transport is a biological process that involves the movement of molecules against the concentration gradient, from an area of lower concentration to an area of higher concentration. This process requires cellular energy, usually provided by ATP (Adenosine triphosphate). Active transport is essential for transporting various molecules such as proteins, large cells, complex sugars, and ions. It plays a dynamic role in the cell and is highly selective. Examples of active transport include exocytosis, endocytosis, and the sodium-potassium pump.
- Primary Active Transport: Direct use of energy, typically ATP, to transport molecules.
- Secondary Active Transport: Indirect use of energy, utilizing the energy created by primary active transport to transport other molecules.
Passive Transport: Passive transport, in contrast, is the movement of ions and molecules across the cell membrane without requiring energy. This process occurs from areas of higher concentration to areas of lower concentration, following the natural concentration gradient. Passive transport is a physical process and includes mechanisms such as simple diffusion, osmosis, and facilitated diffusion. It is less selective compared to active transport and is involved in maintaining the equilibrium level inside the cell.
- Simple Diffusion: Movement of molecules from an area of higher concentration to lower concentration without the need for a carrier protein.
- Osmosis: Movement of water across a selectively permeable membrane from an area of lower solute concentration to higher solute concentration.
- Facilitated Diffusion: Movement of molecules across the cell membrane with the assistance of a carrier protein.
Key Differences Between Active and Passive Transport:
- Energy Requirement: Active transport requires cellular energy (ATP), while passive transport does not.
- Concentration Gradient: Active transport moves molecules against the concentration gradient, while passive transport moves along the concentration gradient.
- Selectivity: Active transport is highly selective, while passive transport is partly non-selective.
- Speed: Active transport is rapid, whereas passive transport is comparatively slow.
- Direction: Active transport transpires in one direction, whereas passive transport occurs bidirectionally.
Understanding these concepts is crucial for comprehending the fundamental processes that supply nutrients, oxygen, and other essential molecules to cells, as well as the elimination of waste products, ensuring the proper functioning of living organisms.
