RDK PARAMEDICAL STUDENT STUDY

What is difference between gram positive and negative   Most bacteria can be broadly classified as  Gram positive  or  Gram negative .  Gram positive  bacteria have cell walls composed of thick layers of peptidoglycan.  Gram positive  cells  stain  purple when subjected to a  Gram stain  procedure.  Gram negative  bacteria have cell walls  with a  thin layer of peptidoglycan.   Why is it important to know whether bacteria are gram negative or gram positive? If bacteria  are present, this test can also help your doctor  learn if  the  bacteria are gram negative or gram positive . The difference between  gram - negative  and  gram - positive bacteria  can affect their recommended treatment plan.   What are gram negative and positive bacteria   Gram positive bacteria  have a thick peptidoglycan layer and no outer lipid membrane whilst...

Ziehl–Neelsen stain Ziehl-Neelsen staining is a type of acid-fast stain, first introduced by Paul Ehrlich. Ziehl–Neelsen staining is a bacteriological stain used to identify acid-fast organisms, mainly Mycobacteria                                         ZN (ZIEHL-NEELSEN)   Stain for AFB (ACID-FAST BACILLI)   Procedure 1.       Fix the smear of the specimen over the glass slide, either by heating or alcohol fixation. 2.       Poor carbol fusion over smear and heat gently until fumes appear. Do not overheat and allow it to stand for 5 minutes, Then wash it off with water. 3.       Pour 20% sulphuric acid, wait for one minute and keep on repeating this stepuntil the slide appears light pink in colour,...

Difference Between Enriched Media and Enrichment Media   Enriched media  contain the nutrients required to support the growth of a wide variety of organisms, including some fastidious ones. They are commonly used to grow as many different types of microbes as are present in the specimen   Definition Enriched media refers to the media which contain the nutrients required to support the growth of a wide variety of organisms, including some fastidious ones, while enrichment media refers to the liquid media that inhibits the growth of the unwanted bacteria.   Type of Growth Enriched media allow the growth of a wide variety of microorganisms,while enrichment media allow the growth of a particular type of microorganism in the medium. Thus, this is the main difference between enriched media and enrichment media.   Solid or Liquid Apart from that, an important difference between enriched media and enrichment media is that enriched media are solid med...

                              Indole tes Indol test is the biochemical test .This test detection of indoles such as LSD, see  Ehrlich's reagent . The  indole test  is a biochemical test performed on  bacterial species  to determine the ability of the organism to convert  tryptophan  into  indole . This division is performed by a chain of a number of different intracellular  enzymes , a system generally referred to as "tryptophanase.   Indole is generated by reductive  deamination  from tryptophan via the intermediate molecule indolepyruvic acid.  Tryptophanase  catalyzes the deamination reaction, during which the  amine  (-NH 2 ) group of the tryptophan molecule is removed. Final products of the reaction are indole,  pyruvic acid ,  ammonium ...

                               Alternate of Coagulase test   Both  coagulase tests  detect the enzymes that convert fibrinogen into fibrin. Human, rabbit or sheep pooled plasma is used as substrate for both  tests . Slide  coagulase test  is simpler and faster as compared to tube  coagulase test . The plasma could be carrier of many human and animal pathogens like HIV, HBV, HCV etc                      Improperly stored plasma can lead to false  positive  or negative results. Citrated plasma may be unsuitable for this  test if  contaminated with  citrate  utilizing bacteria.   DNA-ase test:   This test is used to help in the identification of S. aureus which produces deoxyribonuclease (DNA-ase) enz...