Prokaryotic Cell Lab Report

Prokaryotic organisms normally have a cytoplasmic membrane, cell wall, and sometimes a capsule. Bacterial cells are most commonly either coccus or bacillus in shape. The cell wall is either Gram positive or Gram negative. When the cell is Gram negative, the cell has an extra layer of lipopolysaccharides. The Gram positive has a thick layer of peptidoglycan. Bacteria usually have capsules, but archaea rarely have one. Inside the prokaryote is cytoplasm and a nucleoid. The nucleus is not enclosed inside of a membrane in prokaryotes. The cell may have appendages to adhere to certain surfaces or for motility. The prokaryotic cell is smaller than the eukaryotic cell and has different qualities that make the cell less complex than a eukaryotic cell.

The media used in this experiment was Trypticase nitrate broth. The reagents used (A and B) were sulfanilic acid and alpha-naphthylamine (respectively). Using aseptic technique, the bacterium (16A and 16B) were inoculated into labeled broth test tubes. The tubes were incubated for 48 hours at 37 degrees Celsius. When the incubation was complete 5 drops of reagent A and 5 drops of reagent B were added to each of the broths. If the broth turned a reddish color, the result was then positive. If there was no color change, then a small amount of zinc powder was added. If there was no color change, the result was also positive, but if there was a red coloration development after the zinc was added, the result was then negative. Both Unknown bacteria (16A and 16B) were positive for nitrate reduction. The tubes were then

S. aureus is a non-motile facultative anaerobic bacteria. This bacteria can survive long periods in the environment; so it is readily transmissible. S. aureus causes a number of medical infections and is the leading cause of wound infections. It is an opportunistic bacteria, and infects any population. It favors the skin, since it is part of the normal flora. Its virulence factor comes from multiple things within the cell and these things contribute to the types of infections they cause. Two important virulence factors are a secreted protein called coagulase and clumping factor. Some other virulent factors are the capsule, enterotoxins, exfoliatin, toxic shock syndrome toxin, and alpha toxin. The enterotoxins cause food poisoning in humans. The exfoliatin caused scalded skin syndrome. Toxic shock syndrome toxin causes rash, diarrhea, and shock in humans. The last virulent factor is the alpha toxin. This makes holes in the host cell membrane. S. aureus causes a number of medical conditions and is not rare or uncommon to the human population or medical knowledge. (Nester, Allen & Salm, 2012, pgs. 275 and