Nucleic Acids Flashcards
Name the two nucleic acids and 2 similarities they both have
1.Deoxyribonucleic acid and ribonucleic acid
2.They are long biopolymers, carriers of information
What are the monomers of nucleic acids called?
Nucleotides
Name three components of a nucleotide
1.Phosphate group
2.Pentose sugar
3.Nitrogenous base
Name the 5 bases
Adenine,Thymine (Uracil in DNA),Cytosine,Guanine
Name the Purines
Adenine, Guanine
Name the Pyrimidines
Cytosine,Thymine (Uracil)
What are the pairs of bases that go together?
AT(U) and CG
What is a nucleoside?
A base bonded to the C1 of a Pentose sugar
What is the difference between a nucleoside and nucleotide?
A nucleotide is a nucleoside with a phosphate group bonded at the -OH of the C5
What is the primary structure of nucleic acids due to?
They are due to the order of the nucleotides
How is a phosphodiester bond created?
The phosphate group bonds to the C5 -OH to form a backbone leading to a polynucleotide
How does DNA link to the numbers 5’ and 3’
The single DNA strand has a phosphate group at C5 -OH and a free -OH at C3
Give a random example to how a single strand of DNA is read
E.g. 5-A-G-C-T-3
Give two facts about the double helix
1.The two strands of DNA wind around each other
2.The hydrogen bonds between base pairs stabilise the helix
How many H bonds does A-T have?
2 Hydrogen bonds
How are the two strands of DNA bonded by H bonds complementary?
The strands are anti-parallel as one starts from 5’-3’ and the other starts as 3’-5’
What is carried on the template strand?
Genetic information is carried on the template strand while the other is an anti-template strand
What charge is the P-S backbone?
The P-S backbone has a negative charge making it hydrophilic and the inside bases are hydrophobic - Increases stability like lipids
What other bonds are between bases?
VDW bonds are between bases
What are the name of the two grooves that lead to winding in the Double Helix?
1.Major groove
2.Minor groove
What are the two grooves in the double helix and what do they do?
- Major and Minor Grooves
2.Grooves help regulatory proteins bind to specific sites on DNA(transcription, Repression, and silences proteins)
How can double strands be separated?
They can be separated by breaking the H bonds via pH or Temperature (>80 degrees)(Phosphodiester bonds unaffected)
When is Tm recorded?
Temperature of melting is recorded when 50% of the helix is separated into singles
What factors could increase Tm?
The more C-G pairs would increase Tm as C-G has 3 H bonds each meaning more H bonds to break
What is the only start Codon?
AUG/ATG is the only start codon
How many codons are there and how many are for stop codons?
64 codons In total
61 code for amino acids (multiple codes for some of the 20 AAs)
3 Stop codons
Three Differences in RNA To DNA
- Always single stranded
- Uracil instead of Thymine
- Ribose instead of Deoxyribose
Name three types of RNA
Messenger RNA (mRNA), Transfer RNA (tRNA), and Ribosomal RNA (rRNA)
