Nucleic Acids Flashcards
What are nucleic acids?
Nucleic acids are made up of carbon, hydrogen, oxygen, nitrogen and phosphorus. They are large polymers made up of nucleotides which are the monomers of nucleic acids. The nucleotides are linked in a chain to form nucleic acids.
What do nucleotides consist of?
- A phosphate group (PO4 -²)
- A pentose sugar (5 carbon atoms)
- A nitrogenous base ( complex organic molecule consisting of 1 or 2 carbon rings + nitrogen)
Nucleotides are also components of?
Coenzymes: NAD, FAD, NADP
How are nucleotides linked together?
Nucleotides are linked together by condensation reactions to form a polymer called a polynucleotide.
The phosphate group at the fifth carbon of the pentose sugar forms a covalent bond with the hydroxyl (OH) group at the third carbon of the pentose sugar of an adjacent nucleotide.
THIS BOND IS CALLED A PHOSPHODIESTER BOND
How are phosphodiester bonds broken?
By hydrolysis. (Addition of water, releasing the individual nucleotides.)
What is DNA made up of?
- A phosphate group
- Pentose sugar: DEOXYRIBOSE
3.nitrogenous base:
adenine, guanine (purines) 2 carbon rings
cytosine, thymine (pyrimidines) 1 carbon ring
Formation of phosphodiester bonds are catalysed by?
DNA polymerase
Formation of phosphodiester bonds are catalysed by?
DNA polymerase
What helps to hold the double helix in place?
Histone proteins
What is semi conservative replication?
Semi conservative replication is when a new DNA molecule is made from an original strand and a new strand
mRNA that has just been made is called?
Pre- mRNA or primary mRna
Introns in mRNA are removed by?
Splicing
What is the start codon on mRNA
AUG
The genetic code of DNA is
Degenerate. It has 20 amino acids and 64 possible codons
What helps to break down ATP into ADP
atp hydrolase
