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2021-05-18

Which best describes the structure of DNA molecule?

Which best describes the structure of DNA molecule?

The right answer to the given question is option A) A double helix. It best describes the structure of a DNA molecule.

Which best describes the structure of DNA answers com?

What best describes the DNA structure? The best description is a double helix of Deoxyribose held together by paired bases adenine thymine, cytosine and guanine.

Which best describes the structure of DNA Brainly?

Explanation: The structure of DNA is best described as a double helix. Together, it looks like a twisted ladder which is also known the double helix.

What is the structure of DNA Brainly?

Answer. It is composed of two strands, it is also best described as a ‘double helix’. The DNA molecule is a polymer of nucleotides. Each nucleotide is made up of a nitrogenous base, a five-carbon sugar (deoxyribose), and a phosphate group.

Why is DNA supercoiling important?

DNA supercoiling is important for DNA packaging within all cells. Because the length of DNA can be thousands of times that of a cell, packaging this genetic material into the cell or nucleus (in eukaryotes) is a difficult feat. Supercoiling of DNA reduces the space and allows for DNA to be packaged.

Why is DNA negatively supercoiled?

Prokaryotes and Eukaryotes usually have negative supercoiled DNA. Negative supercoiling is naturally prevalent because negative supercoiling prepares the molecule for processes that require separation of the DNA strands. Topoisomerases unwind helix to do DNA transcription and DNA replication.

What is meant by DNA topology?

The topology of DNA, which is defined by how the two complementary single strands are intertwined, has been an important consideration since the double helical structure of DNA was first proposed by Watson and Crick in 1953 (1).

What is topology mean?

1 : topographic study of a particular place specifically : the history of a region as indicated by its topography.

What is DNA linking number?

Linking number is a topological property of DNA. In short, writhe is a number of a time DNA double helix is crossed, coiled over each other or the number of time one strand wrap around another strand. As per the Watson and Cricks model, eukaryotic DNA is right handed and negatively supercoiled.

What are Topoisomers of DNA?

Topoisomers or topological isomers are molecules with the same chemical formula and stereochemical bond connectivities but different topologies. Each topoisomer of a given DNA molecule possesses a different linking number associated with it. DNA topoisomers can be interchanged by enzymes called topoisomerases.

What is DNA gyrase enzyme?

DNA gyrase is an essential bacterial enzyme that catalyzes the ATP-dependent negative super-coiling of double-stranded closed-circular DNA. Gyrase belongs to a class of enzymes known as topoisomerases that are involved in the control of topological transitions of DNA.

Can linear DNA Supercoil?

Chromatin forms on both linear and circular plasmid DNA, but supercoiling can only form in intact circular DNA (unless the DNA is extremely long and/or tethered).

What is the difference between linear and circular DNA?

The main difference between linear and circular DNA is that linear DNA consists of two ends in each side, whereas circular DNA does not have an end. Furthermore, the genetic material in the nucleus of eukaryotes is linear DNA while the genetic material of prokaryotes, as well as mtDNA and cpDNA, are circular DNA.

Does linear or circular DNA run faster?

In vivo, plasmid DNA is a tightly supercoiled circle to enable it to fit inside the cell. Therefore, for the same over-all size, supercoiled DNA runs faster than open-circular DNA. Linear DNA runs through a gel end first and thus sustains less friction than open-circular DNA, but more than supercoiled.