The diagram of cell membrane shows that the cell membrane consists of a semipermeable lipid bilayer. The function of cell membrane is to regulate the transport of materials entering and exiting the cell. The diagram of cell membrane in cross-section shows that the main components are phospholipids, cholesterol, integral proteins, peripheral proteins and carbohydrates. The diagram of cell membrane class 9 is important for biology examinations and should be studied carefully.
The cell membrane diagram is given below:
Diagram of Cell Membrane
Table of Content
What is Cell Membrane?
The cell membrane is also known as the plasma membrane. It is found in all cells and separates the internal contents of a cell from its surrounding external environment. The diagram of cell membrane structure shows that it consists of phospholipid bilayer made up of numerous molecular components, such as proteins and cholesterol, some of which have carbohydrate groups linked to them. It is selectively permeable, thereby allowing only specific substances to pass through its lipid bilayer.
Structure of Cell Membrane
The diagram of cell membrane shows its structure clearly. Following components make up a cell membrane:
Phospholipid
- A phospholipid molecules is an amphipathic molecule made up of a hydrophilic polar phosphate “head,” and a hydrophobic non-polar lipid “tail”.
- Cell membrane comprises two layers of phospholipids arranged in a bilayer.
- The interior has hydrophobic lipid tails facing each other.
- Fluid inside and outside the cell contacts outward-facing polar phospholipid heads.
Membrane Proteins
There are two types of proteins that are usually associated with the cell membrane:
Integral Proteins
These are found embedded in the membrane. It is further of three types:
- A channel protein: It is a type of an integral protein which selectively allows particular molecules like ions to pass into or out of the cell.
- Recognition proteins: It functions to identify a cell so that other cells can identify it.
- Glycoprotein: It is a protein that has carbohydrate molecules attached to it, which further extend into the extracellular matrix. The linked carbohydrate tags on glycoproteins facilitates in cell recognition.
Peripheral Proteins
- Found on inner or outer lipid bilayer surface, or attached to integral proteins.
- Serve specific cell functions; e.g., intestinal peripheral proteins act as digestive enzymes.
- Help in nutrient absorption by breaking down molecules for bloodstream passage.
Carbohydrates
- Carbohydrates are found externally, often attached to lipids or proteins forming glycolipids and glycoproteins.
- In eukaryotes, it is crucial for cell recognition and facilitates interactions and information exchange.
- Viral infections often result from viruses binding to cell receptors via carbohydrates.
- Glycoproteins play significant roles in cell adhesion and communication between cells.
Cholesterol
- Cholesterol is found between phospholipids in the cell membrane.
- Provides stability and structure to the membrane.
- Interacts with hydrophobic tails, making them rigid and less permeable.
- Controls membrane fluidity, acting as a buffer against temperature changes.
- Expands range of temperatures for membrane fluidity maintenance.
Conclusion – Diagram of Cell Membrane
In conclusion, the diagram of cell membrane reveals structure and functions of cell membrane , illustrating its importance in maintaining cell homeostasis and facilitating cell communication and interaction with the environment. Studying the diagram of cell membrane class 11 and 9 is crucial as it often asked in the biology examination.
Also Read:
FAQs on Diagram of Cell Membrane
What Structure is the Cell Membrane?
The main structure of the membrane is the phospholipid bilayer that forms a stable barrier between the two aqueous compartments.
What are the Functions of Cell Membrane?
Cell membranes act as barriers. They are semi-permeable, which means that some molecules can diffuse across the lipid bilayer but others cannot.
Who Discovered Cell Membrane?
Schwann discovered the plasma membrane in 1839 and in 1855, Cramer and Nageli coined the term cell membrane.
Why is the Membrane called Mosaic?
The cell membrane is called a mosaic because it is made of multiple macromolecules held together just like a mosaic.
Why is the Cell Membrane a Bilayer?
The main function of the bilayer membrane is to segregate the internal cell contents from the external environment.
What are the Different Types of Cell Membranes?
Cell membranes include plasma membranes, which surround cells, and intracellular membranes, found within cells, such as those in organelles like the endoplasmic reticulum and mitochondria.
What is Cell Membrane and its Diagram?
The cell membrane is the selectively permeable layer that surrounds the cell and acts as a protective barrier. The diagram of cell shows its detailed structure and components.