DNA structure And Analysis Flashcards
At what wavelength can UV light mutate DNA
260 nm
At what wavelength does nucleic acid absorb light
260nm
At what wavelength does Protein absorb light
280nm
Genetic material
Information that is contained in genes and is passed on to the next generation
If information changes it can be seen in the next generation (variability in organisms )
Criteria for genetic material
Replication
Storage of information
Expression of information
Variation by mutation
Replication
Genetic material duplicates and then separates into two daughter cells
Storage of information
A chemical language for the survival of the cell
Genetic material is repository of information that may or may not be expressed in the cell
Expression of information
A cell needs to turn genes on and off
Depends on the needs of the cell at the given time
Variation by mutation
A change in the chemical composition of the DNA that affects the expressed product of DNA
What is the product of DNA
The central dogma
DNA-RNA - protein
Transcription then translation
DNA and RNA are both nucleic acid .True or False
True
What are the 3 essential components of nucleotides in DNA
Nitrogenous bases (A,T,C,G )
Pentode sugar ; deoxyribose
Phosphate groups
What are the 3 essential components of nucleotides in RNA
Nitrogenous bases (A,U,C,G ) Pentode sugar (ribose ) Phosphate groups
Nitrogenous bases + pentose sugar =
Nucleoside
Nucleoside + phosphate groups
Nucleotide
Pyrimidine ring is a __________ membered ring
————— and ————— are pyrimidines
6
Cytosine and thymine (in DNA)
Cytosine and uracil (in RNA )
Purine ring is a __________ membered ring
————— and ————— are purines
9
Guanine and Adenine
(Pure silver (Ag ) Taxi (TC)
The sugar of DNA and RNA is a __________ sugar
Pentose sugar
The sugar of DNA and RNA ;C1
Can accept a nitrogenous base
If C2 on the sugar of DNA and RN HAS AN OH it is DNA .True or false
False it is called ribose and is used for RNA .if it is has an H it is called deoxyribose and is used for DNA
What is C3 and C5 on the pentose sugar important for
It’s important for making polynucleotides
What bond forms between ribose or deoxyribose and a nitrogenous base
A glycosidic bond
Name the ribonucleosides
Adenosine
Cytidine
Guanosine
Uridine
Name the ribonucleotides
Adenylic acid
Cytidylic acid
Guanylic acid
Uridylic acid
Why is the phosphate groups very important to making DNA and DNA
Phosphate groups store energy that help drive the synthesis of DNA and RNA
The phosphate groups are the structural backbone of DNA and RNA
Why are Nucleoside triphosphats important
There are large amounts of energy that is released when you break the bonds between the phosphate groups
This energy is used to drive the synthesis reaction (making polynucleotides)
What is the linkage between two mono nucleotides
Phosphate group linked to two sugars (phosphodiester )
Each polynucleotides has a 5’ and 2 ‘ end true or false
False it has 5 ‘ and 3’
What is Chargaffs Rule
A-T base ratio suggested they were In equal amounts
G-C base ratio suggested they were in equal amounts
What is the overall form of form A DNA
Short and broad
What is the overall form of the B form
Long and thin
Describe the structure of DNA
Two Long polynucleotide chains coiled around a central axis forming a right handed double helix
The nitrogenous bases are stacked I’m the center
Two chains connected by base pairing
Chains are anti parallel
Complete turn of helix is 34A
(Major groove 22 A and minor groove 12 A )
How is the Z form of DNA different from A and B form
The Z form is a left handed double helix
How many hydrogen bonds are between A-T and G-C
A-T - two H bonds
G-C - three bonds
The nitrogenous bases are1 __________and the phosphate backbone is 2____________
Hydrophilic / hydrophobic
1 hydrophobic
2 hydrophilic
What are stem loop or hairpin structures
Thus is when RNA has a tendency to fold back on itself and form short regions on complementary base pairing
Secondary structure of RNA (5)
Hairpin loop Bulge loop Multi loop with 3 branches Pseudo-knot Stem
mRNA
Is the template for protein synthesis
rRNA
Structural component of ribosomes for protein synthesis
tRNA
carries amino acids for protein synthesis
Telomerase RNA
Involved in DNA replication at the chromosome ends
RNA primers
Involved in starting off DNA synthesis
SnRNA
Small nuclear RNA which helps process mRNA
Antisense RNA ,micro RNA and siRNA
Involved in gene regulation.
Hyperchromic shift
During unwinding , the viscosity of DNA decreases and the absorbance increases
Molecules with a _________Tm have a ___________ G-C content
Higher
Higher
Molecules with a _________Tm have a ___________ A-T content
Lower
Higher
