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
kirill [66]
3 years ago
15

A bacterial culture is being tested for its ability to reduce nitrate. After incubation and growth of the bacteria in nitrate br

oth, there is no accumulation of gas in the Durham tube. The test for the presence of nitrite is colorless. When zinc powder is added, a bright red color develops. Interpret these results.
Biology
1 answer:
skelet666 [1.2K]3 years ago
8 0

Answer:

All this combination of reactions is summarized in that the bacteria reduced nitrate, that is, they added protons to said compound, giving nitrite as a product.

By promoting the appearance of nitrite and that it increases in its concentrations when the zinc dust is thrown away, it becomes reddish since there was a change in pH, that is, the medium was acidified.

Explanation:

Some bacteria take nitrate as a source and end up generating an oxide reduction reaction that gives nitrite as a product, if this reaction advances in a chain, that is, the nitrite is reduced after the nitrate, the product in the future would be ammonia

You might be interested in
Hershey and Chase used radioactive isotopes to label different parts of the phage. They grew one batch of phage in the presence
AlekseyPX

The sulphur would lable the capsule and the phosphorous the nucleic acid.

<h3><u>Explanation</u>:</h3>

Hershey and Chase experiment included growing of the pages in two batches, one in presence of 35S and other in presence of 32P. They then infected bacterial cells with these phages, cleaned them and then centrifuge the cells to isolate the marked elements in bacterial cells.

This was done to isolate which part of the phage is actually infective. Sulphur being a part of the proteins will mark the capsule whereas DNA having the phosphate bridges will be marked by 32P.

5 0
3 years ago
Can you identify the banding patterns predicted by each model after the second round of replication?Drag the test tubes to the a
grigory [225]

Answer:

Explanation: When this study was carried out by Meselson and Stahl, their findings are compatible with the trend expected by semi-conservative analysis, establishing this as the right template. The two parent strands are split as DNA replicates, and each strand acts as a blueprint for a new DNA strand synthesis.

After the first replication, there are two DNA double helices each marked as superscript 14 N slash superscript 15 N. After the second replication, four double helices of DNA are produced. Three of them are marked as 14 N superscript slash 15 N. Two other DNA was marked as 14 N slash superscript 14 N.

Remember that after a round of testing, Meselson and Stahl were able to rule out the moderate template based on the results. At that point, though, they were unable to rule out the dispersive model because that model predicts the same trend as the semiconservative model. But after two trials, the findings made it possible for them to rule out the dispersive design.

4 0
3 years ago
What is the family of the animal that is aquatic and has fur and external ears?​
Feliz [49]

Answer:

Sea lions!

Explanation:

Hope i helped! :)

3 0
3 years ago
Which of these organisms is not an omnivore?
AnnZ [28]

Answer: c Blue whale

Explanation:omnivore is

an animal or person that eats food of both plant and animal origin.

Blue Whale is a carnivorous animal that despite the fact that it doesn't have proper teeth, survives on a diet that is mainly comprised of krill and small crustaceans, along with the occasional small fish.

5 0
3 years ago
What part of the cell is responsible for delivering things to where they need to go in a cell
marusya05 [52]
The Gogi body is responsible for delivering proteins throughout the cell . But the cell membrane is what controls what comes in or goes out
8 0
3 years ago
Other questions:
  • What is true of a physical change
    9·2 answers
  • Designing and constructing buildings that are energy efficient, economical, and made of recycled materials, is a trend called
    15·1 answer
  • Dora loves dark chocolate. Recently she read the Nutrition Facts panel on the wrapper of her favorite chocolate bar. She was sho
    15·1 answer
  • Hetertrophs convert solar energy into chemical energy true or false
    15·1 answer
  • PLSSS DO THIS I WILL MARK BRAINLESS IF ITS RIGHT
    6·1 answer
  • A child has learned to speak but is not able to understand the rules of a
    10·1 answer
  • Why the birth rate tends to decrease in developed countries
    9·1 answer
  • What did Bill climb to get out of the Nye Lab?
    12·2 answers
  • Cells with limited potential to develop into any type of cells are called
    13·1 answer
  • What can you do with dna after you take it out of an organism.
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!