Prokaryotic cell

• Procaryotic cells are about 10 times smaller than eucaryotic cells.
• A typical Escherichia coli cell is about 1 um wide and 2 to 3 um long.
• Structurally, procaryotes are very simple cells when compared with eu maryotic cells.
• Reproduction of procaryotic cells is by binary Fission the simple division of one cell into two cells, after DNA replication and the formation of a separating membrane and cell wall.
• Embedded within the cytoplasm of procaryotic cells are a chromosome (DNA) Coin) incomes, and other cytoplasmic particles.
• A cell membrane, usually.
• A cell wall, sometimes.
• These latter three structures make up the bacterial cell envelope.
• Depending on the particular type of bacterium, flagella, pili, or both may be observed outside the cell envelope.
• The cell membrane, also known as the plasma membrane or cytoplasmic membrane, is similar in structure and function to the eucaryotic cell membrane.
• The cell membrane controls which substances may enter or leave the cell and is flexible enough that it cannot be seen with a compound light microscope.
• Many enzymes are attached to the cell membrane, and various metabolic reactions take place there.
• Inward folding of the cell membranes, called mesosomes, are where cellular resporation takes place in bacteria.
• In bacteria and other photosynthetic bacteria, infoldings of the cell membrane contain chlophyll and other pigments that serve to trap light energy for photosynthesis.
• Procaryotic cells do not have complex internal membrane systems similar to the ER and Golgi complex of eucaryotic cells.
• The procaryotic chromosome usually consists of a single, long, supercoiled, circular DNA molecule, which serves as the control center of the bacterial cell.
• The procaryotic chromosome is capable of duplicating itself, guiding cell division, and directing ing cellular activities.
• A procaryotic cell contains neither nucleoplasm nor a nuclear membrane.
• The chromosome is suspended or embedded in the cytoplasm.
• The DNA-occupied space within a bacterial cell is sometimes referred to as the bacterial cell.
• Small, circular molecules of double-stranded DNA that are not part of the chromosome (referred to as extrachromosomal DNA or plasmids) may also be present in the cytoplasm of procaryotic cells.
• The semiliquid cytoplasm of procaryotic cells consists of a complex mixture of all the materials required by the cell for its metabolic functions.
• Water is a crucial component of bacterial cells.
• Enzymes are a fundamental part of bacterial metabolism.
• Dissolved oxygen is present in some bacteria.
• Waste products are produced by bacterial cells.
• Essential nutrients are required by bacterial cells.
• Protein is a component of bacterial cells.
• Carbohydrates are a component of bacterial cells.
• Lipids are a component of bacterial cells.
• Within the bacterial cytoplasm, many tiny particles have been observed, most of which are ribosomes, often occurring in clusters called Polyribosomes.
• Cytoplasmic granules occur in certain species of bacteria and may consist of starch, lipids, sulfur, iron, or other stored substances.
• The rigid exterior cell wall that defines the shape of bacterial cells is chemically complex and serves the same functions as the relatively simple structure of eucaryotic cell walls.
• The main constituent of most bacterial cell walls is a complex macromolecular polymer known as peptidoglycan (murein), consisting of many polysaccharide chains linked together by small peptide (protein) chains.
• Some bacteria lose their ability to produce cell walls, transforming into tiny variants of the same species, referred to as L-form or cell wall-deficient (CWD) bacteria.
• Some bacteria have a thick layer of material (known as glycocalyx) located outside their cell wall.
• Glycocalyx is a limy gelatinous material produced by the cell membrane and secreted outside of the cell wall.
• There are two types of glycocalyx: slime Layer and capsule.
• The slime layer is not highly organized and is not firmly attached to the cell wall, it easily detaches from the cell wall and drifts away.
• Bacteria in the genus Pseudomonas produce a slime layer, which sometimes plays a role in diseases caused by Pseudomonas species.