Which statement below best explains DNA replication?

Which statement below best explains DNA replication?

The correct answer is – DNA replication occurs during interphase and duplicates the amount of DNA in a cells nucleus just prior to cell division.

How do the functions of DNA and RNA differ?

DNA is functional is the transmission of genetic information. It forms as a media for long-term storage. RNA is functional is the transmission of the genetic code that is necessary for the protein creation from the nucleus to the ribosome. The DNA is a double-stranded molecule that has a long chain of nucleotides.

What are the 3 major differences between DNA and RNA?

So, the three main structural differences between RNA and DNA are as follows:

• RNA is single-stranded while DNA is double-stranded.
• RNA contains uracil while DNA contains thymine.
• RNA has the sugar ribose while DNA has the sugar deoxyribose.

What are two main differences between DNA and RNA?

There are two differences that distinguish DNA from RNA: (a) RNA contains the sugar ribose, while DNA contains the slightly different sugar deoxyribose (a type of ribose that lacks one oxygen atom), and (b) RNA has the nucleobase uracil while DNA contains thymine.

What is the difference between DNA and RNA extraction?

The main difference between DNA and RNA extraction is that the pH level of DNA extraction is pH 8 whereas the pH level of RNA extraction is pH 4.7. DNA and RNA extraction are the two procedures involved in the isolation and purification of nucleic acids from the cells of tissues. Both procedures consist of three steps.

What are the 4 basic steps for DNA extraction?

What does DNA extraction involve?

1. Breaking cells open to release the DNA.
2. Separating DNA from proteins and other cellular debris.
3. Precipitating the DNA with an alcohol.
4. Cleaning the DNA.
5. Confirming the presence and quality of the DNA.

What is the principle of RNA extraction?

The principle of this single-step technique is that RNA is separated from DNA after extraction with acidic solution consisting guanidinium thiocyanate, sodium acetate, phenol, and chloroform [13].

Why Liquid nitrogen is used in RNA extraction?

To harvest leaves and preserve RNA, samples must be frozen rapidly, usually by submersing in liquid nitrogen. To preserve the RNA the samples must be held below -120°C, the glass transition temperature of water. At this temperature all biological activity ceases.

What is the role of TRIzol in RNA extraction?

TRIzol® reagent is an acid-guanidinium-phenol based reagent ideally designed for the extraction of RNA (as well as DNA and protein) from various biological sample inputs. The low pH (acidic) of TRIzol® controls to separate RNA from DNA and protein, while a high pH can cause RNA and DNA to be isolated together.

Is RNA stable in TRIzol?

Cell lysis only takes a few minutes per well, but tissue homogenisation can take 10-20 minutes per sample depending on how tough the tissue is. RNA is stable in trizol which deactivates RNases. You can take a break at this point keeping the sample in trizol for a short time or freezing it for a longer one.

Is RNA stable at?

RNA is generally stable at -80° C for up to a year without degradation. For long term storage, RNA samples may also be stored at -20°C as ethanol precipitates.

How does TRIzol maintain RNA integrity?

TRIzol® Reagent maintains the integrity of the RNA due to highly effective inhibition of RNase activity while disrupting cells and dissolving cell components during sample homogenization. The simplicity of the TRIzol® Reagent method allows simultaneous processing of a large number of samples.

Why is chloroform used in RNA extraction?

It is used to promote phase separation so that RNA is isolated from DNA and proteins in a biological sample. After solubilization, the addition of chloroform causes phase separation, where protein stays in the bottom organic phase, DNA resolves as the interface, and RNA is extracted to the top aqueous phase.

Why Phenol is used in RNA extraction?

Extraction of DNA containing samples with acidic phenol results in the denaturation of the DNA, and once denatured, the DNA partitions to the organic phase. This is a key feature of many RNA purification protocols, which is one of the reasons acidic buffer-saturated phenol is used.

Why Isopropanol is used in RNA extraction?

Since DNA is insoluble in ethanol and isopropanol, the addition of alcohol, followed by centrifugation, will cause the DNA proteins to come out of the solution. In addition, isopropanol is often used for precipitating DNA from large volumes as less alcohol is used (see protocols below).

Why is cold isopropanol used in DNA extraction?

Because DNA is less soluble in isopropanol, isopropanol allows precipitation of larger species and lower concentrations of nucleic acids than ethanol, especially if you incubate at low temperatures for long periods of time.

Why is 70 ethanol used in DNA extraction?

DNA is washed with 70% ethanol to remove some (or ideally all) of the salt from the pellet. because precipitation in 100% ethanol cause removal of all water molecule from DNA and Complete Dehydration,which make them not soluble, So we give 70% wash to let it retain some water molecule when make it soluble.

What is TRIzol reagent?

TRIzol Reagent is a ready to use mixture of phenol, guanidine isothiocyanate, red dye and other proprietary components that can be used to isolate total RNA in 1 hour in a single step. DNA and proteins can be recovered with sequential precipitation from the organic phase.

What is the pH of TRIzol?

Table 2.

		Purity (A260/280)
		Low (<1.7)
Concentration (ng/μL)	High (>25)	CTAB, pH 5 TRIzol, pH 5

How does TRIzol reagent work?

TRIzol Reagent is a ready-to-use reagent used for RNA isolation from cells and tissues. TRIzol works by maintaining RNA integrity during tissue homogenization, while at the same time disrupting and breaking down cells and cell components.

How do you make TRIzol reagent?

Method

1. Grind ~100 mg tissue in LN2 in a 10 ml polypropylene tube and a glass rod.
2. Transfer powder to 1.5 mL tube (approx 1/4th of the tube filled with powder)
3. Add 1.2 ml TRIzol (TRIzol is best 1:10 (1 g 10 ml), but 1:5 and 1:2 works also fine)
4. Mix well by inverting, and make sure the mixture is completely molten.