Difference Between Plasma Membrane and Cell Wall

blog banner
blog banner

Difference Between Plasma Membrane and Cell Wall: Every cell's plasma membrane, a flexible phospholipid bilayer, functions as a bouncer, choosing to admit nutrients in and ejecting trash. It also maintains the form of the cell and interacts with neighbouring cells. The hard cell wall, consisting of cellulose, chitin, or peptidoglycan, wraps around the plasma membrane of plants, bacteria, and certain fungi, providing extra protection and support, similar to a strong castle wall. While both are necessary for cell survival, the dynamic nature of the plasma membrane contrasts with the static strength of the cell wall, making them a fascinating duo in the world of microbes.

Difference between Plasma Membrane and Cell Wall

Both the plasma membrane and the cell wall act as outer barriers for cells, but they differ in their structure, function, and presence in various organisms. Here's a quick breakdown of their differences:


Plasma Membrane

Cell Wall


Lipids, proteins, carbohydrates

Cellulose (in plants), chitin (in fungi), peptidoglycan (in bacteria)


Surrounds cytoplasm

Primarily in plant, fungal, and bacterial cells (absent in animal cells)


Flexible, selectively permeable

Rigid, provides structural support


Regulates passage, maintains integrity

Structural support, prevents lysis, gives shape


Selectively permeable

Generally less permeable

Presence of Pores

Protein channels, transporters

Lacks pores, may have plasmodesmata (in plants) for communication

Response to Osmotic Pressure

Changes shape in response to pressure

Prevents excessive water uptake, maintains turgor pressure

Repair and Growth

Repairs itself, involved in growth

Does not repair, new material added during growth


Present in all living cells

Found in plants, fungi, bacteria (absent in animals)


Thin (7-10 nm)

Thicker than plasma membrane

Browse Best Scrubs Collection

What is Plasma Membrane?

The plasma membrane, found in all living things, is the bouncer of the cell. It's a thin, flexible barrier built from fat molecules that controls what enters and leaves, keeping the good stuff in and the bad stuff out. Think of it as a picky gatekeeper for the cell's inner workings.

Key Features of Plasma Membrane:

  • Fluid mosaic: Imagine a pond with phospholipid molecules forming a double layer like water lilies, with proteins embedded like floating leaves. This dynamic structure allows for movement and flexibility.
  • Selectively permeable: This "gatekeeper" controls what enters and exits the cell. It allows essential molecules like nutrients and oxygen in, while keeping waste products and harmful substances out.
  • Communication hub: Proteins on the membrane act as receptors, receiving signals from other cells and the environment, enabling communication and responses.
  • Universal presence: Every cell, from bacteria to humans, has a plasma membrane. It's the fundamental boundary defining the cell's interior.

What is Cell Wall?

The cell wall is like a sturdy suit of armour worn by some cells, mainly those of plants, bacteria, and fungi. It's a rigid layer made of tough materials like cellulose or chitin, providing extra protection and support to the cell, especially against mechanical stress and harmful invaders. Think of it as a castle wall guarding the kingdom within.

Key Features of Cell Wall:

  • Rigid fortress: Unlike the fluid plasma membrane, the cell wall is a stiff, non-living layer. Imagine a sturdy brick wall surrounding the cell, providing structural support and protection.
  • Composition varies: Depending on the organism, the cell wall can be made of cellulose (plants), chitin (fungi), or peptidoglycan (bacteria). Each material offers specific properties and protection.
  • Limited permeability: While some molecules can pass through, the cell wall is generally less permeable than the plasma membrane. This adds an extra layer of defence against harmful substances.
  • Selective presence: Cell walls are absent in animal cells but present in plants, fungi, bacteria, and some algae. They provide additional rigidity and protection needed by these organisms.

Shop Best Lab Coats from Here!

Similarities between Plasma Membrane and Cell Wall

  • Selective Permeability: While the degree of permeability differs, both structures are involved in regulating the passage of substances in and out of the cell.
  • Present in Living Cells: Both are structures found in living cells, although their presence depends on the type of organism.
  • Cellular Communication: Both structures are involved in cellular communication, though the mechanisms differ (e.g., plasmodesmata in plant cells).
  • Essential for Cell Function: Both the plasma membrane and the cell wall are essential for the proper functioning and survival of the cell.

Though often confused, the plasma membrane and cell wall are distinct structures with crucial yet differing roles in the lives of cells. While both act as protective barriers, the plasma membrane, a dynamic phospholipid bilayer found in all cells, selectively regulates what enters and exits, maintaining cellular homeostasis. Conversely, the cell wall, a rigid encasement primarily found in plants, bacteria, and fungi, provides structural support and shape, often surpassing the plasma membrane in its thickness and strength. This fundamental difference between Plasma Membrane and Cell Wall highlights their complementary functions: the plasma membrane governs the dynamic internal environment, while the cell wall, a static fortress, shields the cell from external pressures and threats. Both, working in tandem, ensure the survival and proper functioning of the cell within its ever-changing surroundings.

Check out More Articles
Difference Between Psychosis and Neurosis
Dorsal Vs Ventral
Difference Between Striated and Unstriated Muscles


What is the main function of the plasma membrane and cell wall?

The plasma membrane regulates the passage of substances in and out of the cell, while the cell wall provides structural support and protection to the cell.

How are the structures of the plasma membrane and cell wall different?

The plasma membrane is a phospholipid bilayer with embedded proteins, while the cell wall is a rigid structure composed of cellulose, peptidoglycan, or chitin, depending on the organism.

Do both the plasma membrane and cell wall exist in animal cells?

Animal cells have a plasma membrane but lack a cell wall. Cell walls are typically found in plant, fungal, and bacterial cells.

What is the role of the plasma membrane in maintaining cell homeostasis?

The plasma membrane controls the entry and exit of ions and molecules, ensuring a stable internal environment for cellular processes.

Can materials pass through the cell wall?

Unlike the plasma membrane, the cell wall is porous and allows the passage of water, ions, and certain molecules.