Bio DNA quiz 1
nucleotides are inserted along both sides (unzips)
2nd Step in the separation of the two DNA strands
Chargaff's rule
A = T and C = G is known as?
Purine
Adenine and Guanine
10 billion
After proofreading, there is a final error rate of only 1 in ____ base pairs.
100,000
As new nucleotides are added, there is an error rate of about 1 in _____ base pairs
Hydrogen bonds
Between nucleotide bases
Purines
Double ring structures (A & G)
Seperate
During replication, the two nucleotide chains _____
original new
Each DNA molecule has one _____ strand and one _____ strand
Template
Each separated chain will serve as a ____ for the production of a new DNA chain.
Complimentary
Each strand of the DNA molecules can be used to make another strand during replication. This is because the two sides are ____ to each other.
Hydrogen bonds are broken between the bases
First step in the separation of the two DNA strands?
nucleases
Several enzymes are involved in repairing damaged DNA. Enzymes called _____ cut out damaged sections of DNA.
Pyrimidines
Single ring structures (T & C)
True
T/F: At the end of replication, each DNA molecule has one original strand and one new strand.
True
T/F: DNA replication occurs simultaneously at many sites along the molecul, speeding up the process of repliation.
False
T/F: Damage to DNA can never be repaired
False
T/F: Mutations always cause serious and harmful effects in the organisms in which they occur.
True
T/F: Mutations can sometimes be an advantage by making the organism slightly better suited for its environment
True
T/F: Replication results in two copies of the DNA molecule
False (they're identical)
T/F: The primary purpose of replication is to produce new DNA strands that are very different from the old strands
True
T/F: The process of DNA replication produces an identical copy of the original DNA strand.
False
T/F: The replication of DNA begins at one end of the molecule and procees to the other end.
deoxyribose
The 5-carbon sugar that is in a nucleotide is called?
polymerases
The enzyme ____ fills the resulting gaps with new nucleotides.
Polymerases nucleotide
The enzyme, ______ proofreads the new strand and looks for errors, If a mistake is found, this same enzyme removes the erroneous ______ and replaces it with another.
Hydrogen Nitrogen bases Helicases
The first step in replication is to break the ____ bonds between the ______ bases. This is accomplished by the enzyme _____
DNA polymerase
The main enzyme of replication whose function is to link together individual nucleotides along a template strand is called:
Hydrogen bonds
The paired bases meet across the helix and are joined together by...
2 complimentary hydrogen bonding
The parent molecule has ____ strands of DNA. Each base is paired to its specific partner by ______
Nucleus
The part or the cell where replication occurs
Replication fork
The sites where new nucleotides are added
Pyrimidine
Thymine and Cytosine
Covalent
Type of bond that connects on e nucleotide to the next nucleotide
Add nucleotides to the existing chain Proofreads each DNA strand to insure an exact copy has been made Fills gaps when fixing
What are the functions of DNA polymerase during replication?
Deoxyribonucleic acid
What does DNA stand for?
Half nucleic acid and half protein
What is a chromosome made of?
Where hydrogen bonds are formed A-T, G-C
What is meant by the "base-pairing" rules?
It speeds up the copying of very long DNA molecules
What is the advantage to the multiple sites of replication along the DNA molecule?
To carry information and be a storage area for protein building instruction so of the cell
What is the primary function of DNA
Exposure to chemicals, radioactivity, x-rays, excessive exposure to ultraviolet light
What might cause accidental damage or changes in existing DNA?
They are identical copies
When a DNA molecule is replicated, what is the relationship between the original strand and the newly formed strands of DNA?
Identical cell division
When replication is complete, two ____ copies of the DNA molecule have been produced and the cell is ready to begin ________.
Origins of replication
When replication occurs, it takes place at multiple sites along the molecule called _______
For mitosis and for the organism to grow and reproduce. To know exactly what to do and have even so they can divide
Why is it so important that the DNA molecule be able to make copies of itself?
Ligases
_____ then seal the free ends, making the strand complete.
Mutation
a change in the base sequence of DNA is called a ________
nucleases
enzyme that cuts out damaged segment of DNA?
DNA polymerases
enzyme that fills the gap of removed damaged DNA with new nucleotides?
ligases
enzyme that seals the free ends of the new DNA to the old DNA, making the damaged strand healthy and complete?
nucleosome
the DNA and histone molecules form a bead-like structure called a...
Sugar and phosphate groups
the backbone of a DNA chain is formed by alternating....
Replication
the process of forming an exact copy of the DNA molecules
Hydrogen
type of bond that holds the nitrogen bases to one another across the middle of the helix
helicases
what enzyme "unzips" the DNA molecule forming 2 replication forks?
covalent bond
where arrow is pointing