dna molecule sugar phosphate backbone and nucleotides

#Dna molecule sugar phosphate backbone and nucleotides free#

Finally, RNA primers are replaced with DNA by a special DNA polymerase.The lagging strand contains Okazaki fragments. The synthesis that proceeds in the opposite direction to the replication fork is the lagging strand. The synthesis that proceeds in the direction of the replication fork is the leading strand. DNA synthesis occurs on both strands of the unwound DNA.

DNA polymerase then takes over and makes DNA that is complementary to the unwound DNA.

The primer is made of RNA, but is complementary to the DNA sequence.

Primase gets this started by laying down a short RNA primer on the unwound DNA.

Note, all biological DNA synthesis occurs from the 5' to the 3' end.

Next, you start making DNA that is complementary to the newly unwound/separated DNA.

SSBs stabilize single-stranded DNA by binding to it.

Single-strand binding protein (SSB) is responsible for keeping the DNA unwound after the helicase.

Helicase is responsible for unwinding the DNA at the replication fork.

DNA gyrase (class II topoisomerase) is responsible for uncoiling the DNA ahead of the replication fork.

First, the double stranded DNA must separate, or unwind.

#Dna molecule sugar phosphate backbone and nucleotides free#

Mechanism of replication: separation of strands, specific coupling of free nucleic acids.hybridization is generally used in Southern blotting (probe anneals to target) and plasmid ligation (sticky ends anneal).annealing is generally used in PCR reactions, where primer anneals to the template strand.hybridization = annealing = coming together of complementary strands.reannealing = coming together of the 2 complementary strands after they've been separated.denaturation = separation of 2 complementary strands = caused by high temperature.DNA denaturation, reannealing, hybridization.Because of the complementary nature of base pairing, DNA can transmit genetic information through replication.Function in transmission of genetic information.Complementary strands of DNA hydrogen bond with each other.DNA with high GC content will be harder to break apart. Base pairing specificity: A with T, G with C.The 'helix' in the double helix means that the entire thing is wound up in a spiral.Going from 5' to 3' of one strand means going from 3' to 5' of the other strand. The 2 single-strands are anti-parallel to each other.The 'double' in the double helix means that DNA is found in a double-stranded form - 2 single-stranded chains of DNA stuck to each other via hydrogen bonding of the base pairs.Deoxyribonucleic acid (DNA): double helix, Watson-Crick model of DNA structure.The phosphate group gives DNA its acidity.Base can either be purines A and G (the big ones with 2 rings) or pyrimidines T and C (the small ones with 1 ring).Sugar phosphate backbone = phosphodiester bonds linking the 5' phosphate to the 3' hydroxyl group of the pentose sugar.Nucleoside = base + sugar = Adenosine, Guanosine, Thymidine, Cytidine.Nucleotide = base (Adenine, Guanine, Thymine, Cytosine) + sugar + phosphate.acid = phosphate group gives it acidity.Race for the Double Helix' starring Jeff Goldblum. If you can find it, be sure to show your students ' The In this way, one DNA strand can become two. The single stranded templates dictate which bases get laid down. To replicate, the DNA molecule unzips along the hydrogen bonds. Sequence of Cs, Gs, As and Ts that make us all unique. Part of the molecule, and it is the differences in the repeating These nucleotide bases are the information carrying C and T are single ringed structures called A and G are double ringed structuresĬalled 'purines'. Staircase, are made of the nucleotide bases Cytosine, Guanine,Īdenine, and Thymine. The inside of the molecule, the 'steps' of the Indicated by the 3-prime (3') and 5-prime (5') notation), and are Note that the strands run in opposite directions (this is This part of the molecule is sometimes called the Staircase, are made of deoxyribose sugars alternating with The outsides of the molecule, the railings of the Words, it is a double stranded molecule that twists like a spiral