2.3.1- DNA- Deoxyribonucleic Acid Flashcards
Define the word ‘monomer’.
A molecule that when repeated makes up a polymer
E.g; amino acids are the monomers of proteins and nucleotides are the monomers of nucleic acids.
What is a nucleotide?
A molecule consisting of a five carbon sugar, a phosphate group and a nitrogenous base.
What is a ‘double helix’?
The shape of a DNA Molecule caused by the coiling of the sugar phosphate backbone into a right handed spiral shape.
What is a polynucleotide?
Large molecule that contains many nucleotides.
How are the components of a nucleotide lined together?
Covalent bonding formed by condensation reactions.
What three things do nucleotides form the monomers of?
Nucleic Acids
DNA
RNA
In a nucleotide molecule, explain what carbon he nitrogenous base and the phosphate group are linked to on the sugar residue.
Nitrogenous base linked to C1
Phosphate group linked to C3/5
When do nucleotides become phosphorylated nucleotides?
When they contain more than one phosphate group- e.g. ADP+ATP.
Define what ATP is.
An energy Rich end product of hydrolysis used to provide cellular energy and drive most cellular metabolic pathways that require energy.
What do nucleotides help to regulate?
Many metabolic pathways. E.g; by ATP/ADP.
Nucleotides can be the components of what?
Many coenzymes
E.g. Adenine nucleotides components of co enzymes NADP/ A/NAD+FAD
What are the four types of nitrogenous base that are found in DNA?
T. Thymine.
A. Adenine.
G. Guanine.
C. Cytosine.
Explain the difference in nitrogenous bases between DNA and RNA.
In RNA, all bases that would be thymine become ‘Uracil’.
List three places where DNA is found, in different cell types.
Eukaryotes- in nuclei
Prokaryotes- in cytoplasm
In some virus types
DNA is one of the important macromolecules that make up living organisms. What are the other three?
Proteins.
Carbohydrates.
Lipids.
DNA is a polymer that is made up of what?
Many repeating units of nucleotides.
There are _______ polynucleotide strands in DNA.
Two.
The strands in DNA run in opposite directions, hence are described as ________
Antiparallel.
The covalent bond formed between the sugar residue and the phosphate group in the nucleotide is called what?
Phosphodiester Bond
When do phosphodiester bonds break?
When polynucleotides break down.
What are the two forms of nitrogenous base and how many rings are in these bases?
Purine- two rings.
Pyrimidine- one ring
Categorise the A/T/C/G nitrogenous bases into purine and pyrimidine.
Thymine+Guanine are Pyrimidine- one ring.
Cytosine and Adenine are Purine- two rings.
Adenine and ______ always bond together by ________ hydrogen bonds in the formation of DNA.
Thymine.
Two Hydrogen Bonds.
Cytosine and _________ always pair together in DNA formation by _______ hydrogen bonds between the bases.
Guanine.
Three Hydrogen Bonds.
