Nucleic Acids Flashcards
What are the monomers of nucleic acids?
Nucleotides
Which 3 components make up a nucleotide?
- pentose sugar
- nitrogenous base
- phosphate group
Describe how nucleotides join together
-condensation reactions
-involves loss of water
-forms phosphodiester bonds
-between sugar and phosphate
Which sugar and nitrogenous bases do DNA nucleotides contain?
Sugar deoxyribose
Bases:
- Adenine
- Thymine
- Cytosine
- Guanine
What is the difference between a purine and a pyrimidine, and which DNA bases belong to each group?
Purines are larger and have 2 carbon ring structures (A &G)
Pyrimidines are smaller and only have 1 carbon ring structure (T & C)
Which type of bond forms between complementary base pairs in DNA?
Hydrogen bonds
Which DNA base is complementary to adenine, and how many hydrogen bonds for between them in a molecule of DNA?
Thymine
2 hydrogen bonds
Which DNA base is complementary to cytosine, and how many hydrogen binds form between them in a molecule of DNA?
Guanine
3 hydrogen bonds
Which sugar and nitrogenous bases do RNA nucleotides contain?
Ribose
Bases:
- Adenine
- Uracil
- Cytosine
- Guanine
Which RNA base forms a complementary pair with adenine?
Uracil
What is the general structure of an RNA molecule?
- single-stranded
- one polynucleotide strand
What are the similarities between DNA and RNA?
-Both made up if nucleotides
-Both contain phosphodiester binds
-Both contain pentose sugar, phosphate, nitrogenous bases
-Both contain bases C, G, and A
What are the differences between DNA and RNA?
-DNA is longer than RNA
-DNA is double-stranded, RNA is single-stranded
-DNA contains thymine, RNA contains uracil
-DNA contains deoxyribose, RNA contains ribose
What is semi-conservative replication?
Each of the newly synthesised DNA molecules is made up of one original DNA stand and one new DNA strand
What is the role of DNA helicase in DNA replication?
DNA helicase breaks bonds between complementary bases to unwind the double helix and separate the strand
What is the role of ATP?
To act as an energy source
Which class of biological molecules does ATP belong to?
Nucleotides
How many phosphate groups does ATP contain?
3
What is the name of the sugar in ATP?
Ribose
Which nitrogenous base does ATP contain?
Adenine
Which product of ATP hydrolysis makes other compounds more reactive?
inorganic phosphate
How does adding an inorganic phosphate to another compound affect its reactivity?
Makes it more reactive
Is ATP broken down via hydrolysis or condensation reaction?
Hydrolysis
Name the two products of ATP hydrolysis
- ADP (adenosine diphosphate)
- Pi (inorganic phosphate)
Which enzyme is responsible for synthesising ATP?
ATP synthase
Which feature if ATP means that little energy is lost as heat?
It releases a small amount of energy
Which elements does a water molecule contain?
- Hydrogen
- Oxygen
How many hydrogen atoms does a water molecule contain?
2
