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
Reika [66]
2 years ago
9

Hi I have a question, answer and I will brainliest

History
1 answer:
Lynna [10]2 years ago
8 0
Membranes are primarily composed of a bilayer of lipids (fats).


In addition to lipids, there are proteins, carbohydrates, and combinations of the three within the bilayer, but the barrier that separates the cell from its exterior environment is established by the lipids. It is called a bilayer because, as you can see in the above image, it is formed by sheets of lipids in opposite conformations. How does this occur? By the nature of the lipid - having a polar, hydrophilic head, and a long, hydrophobic. The cells in a sample are separated from each other, often by a physical means such as grinding or vortexing, and put into a solution containing salt. The positively charged sodium ions in the salt help protect the negatively charged phosphate groups that run along the backbone of the DNA.

A detergent is then added. The detergent breaks down the lipids in the cell membrane and nuclei. DNA is released as these membranes are disrupted. To get a clean sample of DNA, it’s necessary to remove as much of the cellular debris as possible. This can be done by a variety of methods. Often a protease ( protein enzyme) is added to degrade DNA-associated proteins and other cellular proteins. Alternatively, some of the cellular debris can be removed by filtering the sample. Finally, ice-cold alcohol (either ethanol or isopropanol) is carefully added to the DNA sample. DNA is soluble in water but insoluble in the presence of salt and alcohol. By gently stirring the alcohol layer with a sterile pipette, a precipitate becomes visible and can be spooled out. If there is lots of DNA, you may see a stringy, white precipitate. The DNA sample can now be further purified (cleaned). It is then resuspended in a slightly alkaline buffer and ready to use.
You might be interested in
What territories did cyrus successors add to the persian empire?
Sophie [7]
Egypt,to the Indus River, Thebes, and Greece
3 0
3 years ago
How are votes distributed in the United Nations General Assembly?
Dmitrij [34]

the correct answer is A

each nation ahs one vote.

the UN general assembly has a one nation one vote policy. each nation is entitled to one vote. however, all the resolutions of the assembly touching on security must be approved by the security council, where five states sits in the permanent council, and possess veto powers.

3 0
3 years ago
Read 2 more answers
When does Robinson Crusoe begin to build his castle?
swat32
The answer is C because its the day after the shipwreck sinks.
4 0
3 years ago
What do you call the process of cultural traits spreading from one culture to another?
ddd [48]

Answer:

cultural diffusion

Explanation:

Cultural Diffusion. The spread of culture traits from one region to another is called cultural diffusion.

6 0
3 years ago
I NEED THE ANSEWR QUICK how did the united states acquire the louisiana purchase? a. Buying it from france b.By buying it from g
kari74 [83]

Answer:

a. Buying it from France

Explanation:

Thomas Jefferson was the president at the time of the purchase. He purchased the land from Napoleon of France for $15 million.  

7 0
3 years ago
Other questions:
  • In some cases concerning _____, a governor may refuse to extradite a fugitive. terrorist acts bank robbery child custody violent
    5·2 answers
  • The Trail of Tears took place in <br><br> 1830<br> 1835<br> 1838
    14·1 answer
  • What was the song empire was like during healthier times and the bad times?
    10·1 answer
  • What was the name of president truman’s domestic policy
    15·2 answers
  • Need help FAST!! Please
    5·1 answer
  • Which statement describes the U.S. government's reaction to the establishment of a communist state in Russia?
    12·1 answer
  • BRAINLIESTTT ASAP!!
    9·2 answers
  • PLEASE HELP QUICK!!!!
    5·1 answer
  • Civil rights groups disagreed as to how to approach bettering the lives of African
    12·1 answer
  • Helppppppppppppppppppppppppppppppppppppppppppppppppppppp me plz
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!