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How does the double helix stay together?

How does the double helix stay together?

The DNA double helix is held together by hydrogen bonds between the bases attached to the two strands. The DNA double helix. The two sides are the sugar-phosphate backbones, composed of alternating phosphate groups and deoxyribose sugars. The nitrogenous bases face the center of the double helix.

What holds the two strands of a DNA double helix together?

hydrogen bonds
Each molecule of DNA is a double helix formed from two complementary strands of nucleotides held together by hydrogen bonds between G-C and A-T base pairs.

How do the two strands of DNA stay together?

The two strands are held together by hydrogen bonds between the bases, with adenine forming a base pair with thymine, and cytosine forming a base pair with guanine.

What kinds of forces hold the double strands of a DNA double helix together do the two strands go in the same direction or in opposite directions?

Covalent bonds occur within each linear strand and strongly bond the bases, sugars, and phosphate groups (both within each component and between components). Hydrogen bonds occur between the two strands and involve a base from one strand with a base from the second in complementary pairing.

What holds the two complementary strands together?

The hydrogen bonding between complementary bases holds the two strands of DNA together. Hydrogen bonds are not chemical bonds. They can be easily disrupted. This permits the DNA strands to separate for transcription (copying DNA to RNA) and replication (copying DNA to DNA).

Which of the following holds DNA strands together?

The answer is a) Hydrogen bonds. The double strand of the DNA molecule is held together by hydrogen bonding.

What happens to the two strands of a DNA double helix once it is copied during replication?

During DNA replication, each of the two strands that make up the double helix serves as a template from which new strands are copied. The new strand will be complementary to the parental or “old” strand. Each new double strand consists of one parental strand and one new daughter strand.

What force holds DNA strands together?

DNA is constructed of two strands, consisting of sugar molecules and phosphate groups. Between these two strands are nitrogen bases, the compounds which make up organisms’ genes, with hydrogen bonds between them. Those hydrogen bonds have sometimes been seen as crucial to holding the two strands together.

What intermolecular forces stabilize the double helix structure of DNA?

The structure of the DNA helix is stabilized by van der Waals forces, hydrogen bonds between complementary organic bases (a base pair), and hydrophobic interactions between the nitrogenous bases and the surrounding sheath of water.

Why do DNA strands stay together?

The two strands of DNA stay together by H bonds that occur between complementary nucleotide base pairs. While each hydrogen bond is extremely weak (compared to a covalent bond, for example), the millions of H-bonds together represent an extremely strong force that keeps the two DNA strands together.

How is the backbone of DNA a double helix?

A Double-Helix Structure. DNA has a double-helix structure, with sugar and phosphate on the outside of the helix, forming the sugar-phosphate backbone of the DNA. The nitrogenous bases are stacked in the interior in pairs, like the steps of a staircase; the pairs are bound to each other by hydrogen bonds. The two strands of the helix run in

How are the two strands of DNA held together?

These bases bind together in pairs, forming weak bonds that nonetheless hold the two strands of DNA in a double helix together.

How is adenine formed in the double helix?

Adenine forms hydrogen bonds (or base pairs) with thymine, and guanine base pairs with cytosine. During DNA replication, each strand is copied, resulting in a daughter DNA double helix containing one parental DNA strand and a newly synthesized strand.

Where are the bases located in a double stranded DNA molecule?

Antiparallel StrandsIn a double stranded DNA molecule, the two strands run antiparallel to one another so that one strand runs 5′ to 3′ and the other 3′ to 5′. The phosphate backbone is located on the outside, and the bases are in the middle. Adenine forms hydrogen bonds (or base pairs) with thymine, and guanine base pairs with cytosine.