It is a tough and rigid structure of peptidoglycan with accessory specific materials eg. Let us learn about morphology and ultrastructure of a bacterial cell.
The Schematic Diagram Of Bacterial Cell Structure Download Scientific Diagram
Cell envelope of prokaryote 7.
Bacterial cell structure diagram. The cytoplasm is enclosed by three layers the outermost slime or capsule the middle cell wall and inner cell membrane. They have an outer cell wall that gives them shape. Size of a bacterial cell 2.
Different species of bacteria have varying shapes and sizes but generally bacteria have a size range of 05 um to 03 um in diameter and 05 um to 10 um in length. The major cytoplasmic contents are nucleoid plasmid ribosome mesosome etc and the cell is devoid of endoplasmic reticulum mitochondria centrosome and golgi bodies. The cell envelope is composed of the cell membrane and the cell wallas in other organisms the bacterial cell wall provides structural integrity to the cell.
The cytoplasm enclosed within the cell membrane does not exhibit much structure when viewed by electron microscopy. It is 10 25 nm in thickness. Structure of cell membrane 6.
25 shows a typical prokaryotic structure. Ultra structure of bacterial cell 4. A thick layer of glycocalyx bound tightly to the cell wall is called capsule.
The single circular double stranded chromosome is the bacterial genome. Just under the rigid cell wall is the more fluid cell membrane. It gives shape to the cell.
It protects cell from desiccation and antibiotics. Bacteria prokaryotes are simple in structure with no recognizable organelles. Some bacteria are surrounded by a gelatinous substance which is composed of polysaccharides or polypeptide or both.
Structures outside the cell membrane 5. In prokaryotes the primary function of the cell wall is to protect the cell from internal turgor pressure caused by the much higher concentrations of proteins and other molecules inside the cell compared to its external environment. The bacterial cell reveals three layers i capsuleglycocalyx ii cell wall and iii cytoplasm figure 19 capsuleglycocalyx.
After reading this article you will lean about. Much of bacterial cell structure is well understood thanks to the successes recorded in special histological techniques and electron microscopy. Bacteria are prokaryotes lacking well defined nuclei and membrane bound organelles and with chromosomes composed of a single closed dna circle.
Shape and arrangement of bacterial cell 3. They come in many shapes and sizes from minute spheres cylinders and spiral threads to flagellated rods and filamentous chains. A bacterial cell fig.
Lps teichoic acid etc surrounding the bacterium like a shell and lies external to the cytoplasmic membrane.