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Furthermore, the cell wall lacks receptors while the cell membrane has receptors that facilitate cell communication. Question 2: What exactly is a cell membrane? Answer 2: Cell membrane, whose other name is the plasma membrane, is a double layer of proteins and lipids surrounding a cell.
The plant cell wall is made up of cellulose, on the other hand, the fungal cell is made up of chitin. And the bacterial cell is made up of peptidoglycan. The cell wall is a very rigid and thick structure of 4 to 20 um and is visible through the light microscope. Difference between the Plasma Membrane and Cell wall
The cell membrane, or plasma membrane, is a biological membrane that surrounds the cytoplasm of a cell. In animals, the plasma membrane is the outer boundary of the cell, while in plants and prokaryotes it is usually covered by a cell wall. It is flexible and elastic. A cell membrane is called a selectively permeable membrane.
Cell membrane offers shape and rigidity to the cell. In the case of the plant cells, besides the cell membrane, there is also an outer thick layer that is known as the cell wall. This additional layer which surrounds the cell membrane is necessary for offering the requisite protection to the plants.
Prokaryotic cells lack both, a well-defined nucleus and membrane-bound cell organelles. Examples of prokaryotes are blue-green algae, bacteria and mycoplasma. Among prokaryotes, bacteria are the most common and multiply very fast. They are single-celled and range in size from 0.2 to 10 microns (about 10 times smaller than most plant and animal ...
Xylem elements contain the tracheids and vessels. These help in the conduction of water. They are long tube-like structures with partially or completely dissolved walls to form water pipes (in vessels) and pits in the cell wall (in tracheids) for conducting water. Sieve tubes are slender tube-like structures with their end walls perforated by ...
The primary cell wall of land plants is composed of the polysaccharides cellulose, hemicelluloses, and pectin. Algae possess cell walls made of glycoproteins and polysaccharides such as carrageenan, cellulose, hemicellulose and pectins and agar that are absent from land plants. In bacteria, the cell wall is composed of peptidoglycan.
∙ The cell walls of adjacent plant cells are glued together by the middle lamella. ∙ Middle lamella is a jelly-like substance made up of calcium and magnesium pectate. ∙ Cellulose and hemicellulose are the polysaccharides present in the cell wall which provides the mechanical support of the plant cell.
Cell wall consists of three layers: the primary cell wall, secondary cell wall and the middle lamella. The middle lamella- It is the first layer formed du ring cell division. This layer is rich in pectin. It is the outermost layer, joins together adjacent plant cells and holds them together.
The process of cell walls construction of diatoms is known as Frustule. It has two thin overlapping shells fitting into each other just as a soap-box. Their walls are made up of silica. The dead and decomposed diatoms deposit the sillica present in their walls in form of diatomaceous earth. This diatomaceous earth is very soft and quite inert.
