BACTERIAL MORPHOLOGY CONTD...

STRUCTURE INTERNAL TO CELL WALL:

2.) Cytoplasm:  It refers to internal matrix of cell inside the cytoplasmic membrane. Prokaryotic cytoplasm lacks membrane bound structures . The cytoplasmic matrix is largely watered which dissolves proteins, amino acids, sugars, nucleotides, salts,  vitamins, & ions. It also contains certain bacterial structures like inclusion bodies, nucleoid, plasmids.

A) Ribosomes:   They are r-RNA protein bodies which give granular appearance.  Proteins  are synthesized in ribosomes & prokaryotic. Proteins are synthesized  in ribosomes & prokaryotic ribosomes aren't bound to endoplasmic  reticulum. Ribosomes of prokaryotes are called 70S(Sedimentation Coefficient) & are composed of 2 units(50S & 30S). Antibiotics such as Streptomycin &Tetracycline prevents bacterial ribosomes from carrying out protein synthesis.

B). Nucleoid:   It is an irregular shape region where prokaryotic chromosomes are located. The nucleoid doesn't contain membrane as eucaryotic cells. The bacterial chromosomes is a closed loop of DNA that contains the hereditary information or genes of the cells.

C) Plasmids:  They are extra chromosomal DNA molecules usually circular & replicate independently of the chromosomes or they may be  integrated with chromosome. They are not required  for host growth & reproduction but are significant in disease process. Some plasmids process genes for toxin substances & may carry genes for drug resistance which can spread throughout the population.  

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