1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Yuliya22 [10]
3 years ago
7

One of your lab partners has followed the recommended procedure of running Gram-positive and Gram-negative control organisms on

her Gram stain of an unknown species. Her choices of controls were Escherichia coli and Bacillus subtilis. She tries several times and each time concludes she is decolorizing too long because both controls have pink cells (one more than the other). What might you suggest she try and why?
Biology
1 answer:
andreyandreev [35.5K]3 years ago
7 0

Answer:

Reduced in holding time of decolrization step and also used less Alcohol because decolrization step is important in Gram's staining.The decolorization step must be performed carefully. Otherwise over-decolorization may occur. This step is critical and must be timed correctly otherwise the CV stain will be removed from the Gram-positive cells. If the decolorizing agent is applied on the cell for too long time, the Gram-positive organisms to appear Gram-negative..

Explanation:

Gram' staining is a technique used in microbiology labs to differentiate between Gram's positive and negative

<u>Gram-positive bacteria :</u>Stain dark purple due to retaining the primary dye called CV in the cell wall.

<u>:Gram-negative bacteria </u>Stain red or pink due to retaining the counter staining dye called Safranin or neutral red.

There are four basic step in Gram" staining

1) Application of the Primary Stain to a Heat-Fixed Smear of Bacterial Culture

2)Addition of Gram's Iodine

3)<u>Decolorization with 95% Ethyl Alcohol:</u>Alcohol or acetone dissolves the lipid outer membrane of Gram-negative bacteria, thus leaving the peptidoglycan layer exposed and increases the porosity of the cell wall. The CV-I complex is then washed away from the thin peptidoglycan layer, leaving Gram-negative bacteria colorless.

On the other hand, alcohol has a dehydrating effect on the cell walls of Gram-positive bacteria that causes the pores of the cell wall to shrink. The CV-I complex gets tightly bound into the multi-layered, highly cross-linked Gram-positive cell wall thus staining the cells purple.

The decolorization step must be performed carefully. Otherwise over-decolorization may occur. This step is critical and must be timed correctly otherwise the CV stain will be removed from the Gram-positive cells. If the decolorizing agent is applied on the cell for too long time, the Gram-positive organisms to appear Gram-negative. Under-decolorization occurs when the alcohol is not left on long enough to wash out the CV-I complex from the Gram-negative cells, resulting in Gram-negative bacteria to appear Gram-positive.

You might be interested in
Can you pls pls help me?
ValentinkaMS [17]

Answer:

the last one because

Explanation:

matter is not created or destroyed so everything that you put in the solution will make up the mass

5 0
2 years ago
Read 2 more answers
consider the following at 8 p.m. a diabetic is found to have a blood pH of 7.33 is Brian tells his diaphragm to contract more fr
Radda [10]

Answer:

Considering that homeostasis is restored in the patient, his blood pH range would return to normal levels (7.35-7.45), and his hydrogen ion concentration in the blood would normalize. The effect of normalizing the body by getting rid of excess hydrogen ions is achieved by concentrating these ions into the urine for expulsion, therefore increasing the pH levels of urine.

Medical Disclaimer: The information on this site is for academic purposes only and is not a substitute for professional medical advice.

Explanation:

Acidosis is the condition wherein excessive acid build-up within the body causes the blood pH to become lower than normal (normal pH range 7.35-7.45). This may be due to an excessive loss of bicarbonate in the blood, also known as metabolic acidosis, or due to an impairment in the elimination of carbon dioxide in the blood from poor lung function, also known as respiratory acidosis. The body's natural response to acidosis is to increase the breathing rate to eliminate carbon dioxide in the blood, restoring the natural pH of the body.

In people with diabetes mellitus type I, the lack of insulin causes cells to breakdown fat aside from glucose as an energy source. This process produces ketones as a metabolic by-product for energy but also causes the body to be acidic. This is known as diabetic ketoacidosis.

7 0
3 years ago
Is hepatitis B the most common bloodborne pathogen?
IrinaK [193]

Answer:

No.

Explanation:

Hepatitis C is the most common bloodborne pathogen.

Hepatitis C as of 2022 has a infection rate of 3.7 million.

Hepatitis B as of 2022 has a infection rate of 2.2 million, or <em>1.5 million</em> lower than Hepatitis C.

Therefore, Hepatitis B is not the most common bloodborne pathogen.

Learn more about Hepatitis B, here:

brainly.com/question/6284143  - The three bloodborne pathogens healthcare workers in the US are most likely to be exposed to.

5 0
2 years ago
Apoptosis involves all but which of the following?
LenaWriter [7]

Answer:

Apoptosis does not involve:

c. lysis of the cell

Explanation:

Apoptosis is a programmed cell death that occurs under normal physiological conditions and in a controlled manner. Normally seen in cell turnover, embryogenesis, also involved in processes of immune, nervous and endocrine systems.

The main morphological and biochemical changes seen during the apoptosis are the fragmentation of DNA by endonucleases, nuclear, chromatin and cytoplasmatic condensation, apoptotic bodies formation (membrane bound-vesicles form of cell parts) and the phagocytosis (digestion) of those bodies by the scavenger cells.

Apoptosis is regulated by cell- signaling pathways, the caspases, a family of cysteine proteases, are the ones involved in the process.

In the process there is no lysis of the cell as this could lead to a inflammatory response (just happens in necrosis) which would affect contiguous cells, and will involve immune cells. In apoptosis there is just a membrane blebbing, but it does not loss its integrity.

4 0
3 years ago
This is the truth xD-.-​
crimeas [40]

Answer:

yes po

Explanation:

this is my opinion

6 0
2 years ago
Read 2 more answers
Other questions:
  • The maker of a promissory note is the person who is secondarily liable on the note.
    10·2 answers
  • A geologist finds an unidentified fossilized rock in a box in the attic. What type of dating would the scientist attempt to use
    11·2 answers
  • Read the quotation below: Nature is messy. Science is tentative. As long as these truths remain relevant to biological research,
    9·2 answers
  • Which of the following would accompany a high-fat meal moving through the digestive system?
    10·2 answers
  • How many people in the US are living with AIDS?
    12·1 answer
  • Which component on the earths atmosphere is decreased due to photosynthesis?
    14·2 answers
  • We can determine the velocity of a wave when given the frequency and the
    8·1 answer
  • If you all need help in science let me know
    14·2 answers
  • The following chart lists taxonomy classifications for seven organisms. Some have just one classification, while others have a s
    8·1 answer
  • Progressive degeneration of the retina that affects night and peripheral vision is known as?
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!