Hydrogen bonds between nitrogen and hydrogen accross the covalent bonds involving a free pair of electrons
Its Hydrogen Bonds that hold the two strands of the DNA double helix together.
When two strands of DNA that have exactly complementary base pairing (Adenine bonds with only Thymine, and Cytosine with Guanine) the base forms a hydrogen bond to the base on the opposite strand, only if the base pairing is complementary. So, in short the double helix form is held together by hydrogen bonds between the bases present on the strand. This means as the two strands are split apart, a new complimentary strand is formed against each, resulting in two identical double helices where there was just one before. It is by this means that the instructions for the code of life are copied and passed on.
DNA is a double-stranded molecule twisted into a helix (think of a spiral staircase). Each spiraling strand, comprised of a sugar-phosphate backbone and attached bases, is connected to a complementary strand by non-covalent hydrogen bonding between paired bases. The bases are adenine (A), thymine (T), cytosine (C) and guanine (G). A and T are connected by two hydrogen bonds. G and C are connected by three hydrogen bonds.
First off - it is important to understand that a nucleotide (the monomer of DNA) is composed of 3 things: a sugar, a phosphate group, and a nitrogenous base. Next - understand that the "backbone" of DNA is composed of the sugars and phosphates. That leaves you with nitrogenous bases. Hydrogen bonds form between the nitrogenous bases off opposite strands in the double helix. THIS is what holds the double helix together.
Hydrogen Bonds are the bonds that hold the complimentary bases together. G to C and A to T. However the bonds that hold the nucleotides together on each side of the double helix are called Phosphodiester bonds or linkages.
Generally hydrogen bonds between the different base pairs holds the double helix together.
Hydrogen bonds
The DNA molecule forms a double helix. The linear DNA chromosomes of eukaryotes form a highly supercoiled double helix.
Its Hydrogen Bonds that hold the two strands of the DNA double helix together.
Hydrogen bonds that form between the nitrogenous bases hold the double helix together.
When two strands of DNA that have exactly complementary base pairing (Adenine bonds with only Thymine, and Cytosine with Guanine) the base forms a hydrogen bond to the base on the opposite strand, only if the base pairing is complementary. So, in short the double helix form is held together by hydrogen bonds between the bases present on the strand. This means as the two strands are split apart, a new complimentary strand is formed against each, resulting in two identical double helices where there was just one before. It is by this means that the instructions for the code of life are copied and passed on.
On a single strand of DNA the nucleotides are held together by covalent bonding between the phosphate group bonded to the 5' end of the deoxyribose, which bonds to another deoxyribose molecule attached to the next nucleotide on the strand at the 3' end of the sugar. This is what holds together a single strand. When two strands of DNA that have exactly complementary base pairing (Adenine bonds with only Thymine, and Cytosine with Guanine) the base forms a hydrogen bond to the base on the opposite strand, only if the base pairing is complementary. So, in short the double helix form is held together by hydrogen bonds between the bases present on the strand.
Hydrogen bonds
The chemical bond that holds the double helix together in DNA are the hydrogen bonds. Hydrogen bonds are the weakest making them perfect for DNA replication.
the bases are paired by hydrogen bounds
The ribosomal subunit of a ribosome holds onto the mRNA strand
the nucleus