Biology DNA and replication
Structure do DNA does not have
5- carbon sugar, ribose
Nucleosomes
8 histones and DNA
Mutation
A change in the base sequence of DNA is called
False Twisted
A double helix is shaped like a (straight) latter
Ribose
A sugar with a molucre RNA
Base pairing
A=T C=G
Nitrogen bonds
A=T two hydrogen bonds G=c three hydrogen bonds
True
Across the center of the DNA helix, a purine must always bond to a pyrimidine
False nope
Adenine always bonds to thymine, ( but occasionally it can also bond to cytosine)
True
Alternating sugar and phosphate molecules form side or the backbone of the DNA molecule
Complimentary base pair
Bases linked by a hydrogen bond on opposite strands of DNA of doubled RNA
Nucleosome
Bed like structure formed of several histones with corresponding DNA
Covalent bonds
Bond that connects one nucleotide to the next nucleotide
Hydrogen bonding
Bond that hold the nitrogen bases to one another across the middle of the helix
Radioactivity, x-rays, excessive exposure to sunlight
Causes accidental damage or changes in existing DNA
True
Chemical analysis shows that a chromosome is composed of half protein and half nucleic
Not in a nucleotide
DNA polymerase
True
DNA replication occurs simultaneously at many sites along the molecule, speeding up the process of replication
False always
Damage to DNA can (never)be repaired
Watson&Crick
Discovered the structure of the DNA molecule
Purine
Double ring structures adenine and guanine are purines
Separate
During replication the two nucleotide chains
Template
Each chain will serve as... for the production of a new DNA chain
Complimentary
Each strand of the DNA molecule can be used to make another strand during replication. This is because the two sides are... to each other
Helicases
Enzyme that breaks hydrogen bonds
DNA polymerases
Enzyme that fills the resulting gaps with new nucleotides
DNA polymerases
Enzyme that proof reads the new strand and looks for errors
Nucleases
Enzymes that cut out damaged sections of DNA
Adenine Guanine Thymine Cytosine
Four nitrogen bases found in DNA
What is the advantage to the multiple sites of replication along the DNA molecule?
Helps go faster
Franklin
Her x-Ray crystallography photographs provided the vital clues in solving the structure of DNA
True
Nitrogen bases are bounded together across the center the center of the helix with hydrogen bonds
Nucleus
Part of cell that replication occurs
True
Phosphates are bonded to sugars and sugars are bonded to nitrogen bases with covalent
What are two functions of DNA polymerase during replication?
Proof reads new strands, and fills gaps when fixing
Histones
Protein that helps pack up DNA
True
Replication results in two copies of the DNA molecule
Ligases
Seal the free ends making the strand complete
Sugar and phosphate groups
Sides the DNA latter is made of
Pyrimidine
Single ring structures cytosine and thymine are pyrimidines
Replication forks
Sites where new nucleotides are added
Nucleotides
Small repeating subunits that compose DNA&RNA
Why is it so important that the DNA molecule be able to make copies of itself?
So they can know exactly what to do and have even so they can divide
Function of DNA cell
Stores the information that directs the ribosomes in protein synthesis
Deoxyribose
Sugar in DNA
What is the primary function of DNA?
The DNA is the storage area for the protein building instructions of the cell
Hydrogen, nitrogen bases
The first step in replication is to break the... Bonds between the...
DNA polymerase
The main enzyme of replication whose function is to link together individual nucleotides along a template strand
False identical
The primary purpose of replication is to produce new DNA strands that are very (different) from the old strands
True
The process of DNA replication produces an identical copy of the original DNA strand
Replication
The process of forming an exact copy of the DNA molecule
Histones
The proteins DNA is tightly wound around
False several places
The replication of DNA begins at one end of the molecule and proceeds to (the other end)
False Four
There are (five) nitrogen bases in the DNA molecule
False a
There is (no) difference between the sugar found in DNA and the sugar in RNA
Hydrogen bonds
What holds together the two sides of the DNA molecule across the center of the helix
Nitrogen bases
What the rungs of the DNA latter is made of
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