General q
What are the names of the two nitrogen-containing heterocyclic aromatic ring structures ?
Pyrimidine & purines
nucleic acid is required for what?
the storage and expression (transfer) of genetic information.
Purine is a single 6 membered ring containing 2 nitrogen atoms. T or F
False it's a fused ring system containing a 6 membered ring with 2 nitrogen atoms and a 5 membered ring with 2 nitrogen atoms.
Under cellular pH conditions what charge does phosphoric acid have?
-2. charge
Structural difference between D-ribose & D-deoxyribose .
D-ribose has a hydroxyl group in 2‘ but deoxyribose doesn’t
Which compound from the pyrimidines is found only in RNA?
Uracil
What is the function of a gene?
To direct the synthesis of specific protein
ATP is another function of nucleic acid ? T or f
True and it’s the universal currency of energy
The nucleotide bases are usually attached to which position?
Attached to 1’ position of the sugar
What are 3 things that nucleotides are composed of:
• pyrimidines and purines
• Ribose or 2-deoxyribose
• Phosphate
Who is the two scientist that discovered nucleic acid?
Francis crick & james watson
The complementary strands in DNA are held by what bonds?
Hydrogen bonds
The bases in DNA run outward: t or f
False inward
how many chromosomes does human cell contain?
46
How are replication forks formed ?
When two strands open creating a y-shaped region.
What does semiconservative replication mean?
The process by which a new DNA molecule is produced that has one strand from the parent and a new complementary strand.
Which compound from the pyrimidines is found only in DNA?
DNA has to be copied before a cell divides? T or F
True
How many genes does a human cell contain?
20,000
Each chromosome contains what?
One molecule DNA , and histones which are small basic proteins.
What is the secondary structure of DNA?
Double helix
What is the linkage called in nucleic acid?
3’,5’ Phosphodiester
The phosphate is generally located at the 4’ position ? t or f
False its located at the 5’ position
How many replication bubbles are in prokaryotic cells and eukaryotic cells?
Prokaryotes have a single bubble, and prokaryotes have many bubbles
Name the complementary bases in DNa and the number of hydrogen bonds it has?
Adenine and thymine , and has 2 hydrogen bonds
Guanine and cytosine , and has 3 bonds between them