Biological molecules 2 Flashcards
What are nucleotides made up of?
-5 carbon pentose sugar
-Nitrogen-containing base
-Phosphate group
What are the functions of nucleotides?
-Energy currency for a cell (ATP)
-Building blocks for DNA and RNA
How many nitrogen-containing rings does a purine base have?
Two
How many nitrogen-containing rings does a pyrimidine base have?
One
What the two most common purine bases?
Adenine and guanine
What the three most common pyrimidine bases?
Cytosine, thymine and uracil
What makes nucleotides carry a negative charge?
The phosphate group
How is the sugar, base and phosphate group joined together?
Condensation reaction
How many phosphate groups does ATP have?
Three
What happens when energy is needed in a cell?
-The third phosphate bond is broken by a hydrolysis reaction
What enzyme breaks down ATP?
ATPase
What product is formed from the breakdown of ATP?
Adenosine diphosphate (ADP)
What are nucleic acids made up of?
Many nucleotide monomer units
What is the function of nucleic acids?
Carries all the information needed to form new cells
How are nucleic acids made?
Condensation reaction
What are the bonds in nucleic acids?
Phosphodiester bonds
What bases are present in RNA?
C, G, A and U
What bonds hold together bases?
Hydrogen bonds
How many bonds are between C and G?
Three bonds
How many bonds are between A and T?
Two bonds
What happens in semi-conservative replication?
The DNA unwinds and new nucleotides align along each strand
What happens in conservative replication?
The double helix remains intact and new strands form
Which enzyme catalyses the unwinding of DNA?
DNA helicase