The Structure of DNA
DNA is an example of...
Nucleic Acid
What was the breakthrough model of DNA that came from Watson and Crick?
Double Helix
What do base pairing in the double helix explain?
How DNA can be copied, or replicated.
True or False. DNA replication is carried out during the S phase of the cell cycle by a series of cells.
False
The observation that A=T and G=C became known as...
Chargaff’s Rule
What are formed by pairs of nitrogenous bases?
Rungs of the DNA double helix
What does each strand of the double helix of DNA serve as?
Template or Model.
DNA polymerase also “__________” each new DNA strand, so that each molecule is a near-perfect copy of the original.
Proofreads
Nucleic acids are long, slightly acidic molecules built from small monomers called...
Nucleotides
True or False. Hydrogen bonds form only between certain base pairs.
True
What is replication?
Before a cell divides it duplicates its DNA in a copying process.
True or False. The principal enzyme involved in DNA replication is called DNA polymerase.
True
Each DNA is made up of three components...
1. Deoxyribose
2. Phosphate group
3. Nitrogenous Base
What is the most important aspect of the double helix model?
Its two strands of DNA run in opposite directions.
DNA Replication occurs during what phase?
S
In __________ the enzyme telomerase may be activated enabling these cells to grow and proliferate rapidly.
Cancer
What are the four kinds of nitrogenous bases?
Adenine, Guanine, Cytosine and Thymine.
What forms between certain nitrogenous bases, providing just enough force to hold two strands together?
Hydrogen Bonds
In rapidly dividing cells, _____________ helps to prevent genes near the ends of chromosomes from being ____________ or lost during replication.
Telomerase, and Damaged.
What checks DNA for chemical damage or base pair mismatches prior to replication?
Proteins