Nucleic Acids Flashcards
_______ are a linear polymer of nucleotides that function in the storage and expression of genetic information and its transfer from generation to the next
- nucleic acids
The two types of nucleic acids
- ribonucleic acids (RNA)
2. deoxyribonucleic acids (DNA)
DNA and RNA are ____________ chains
- polymeric chains
DNA/RNA polymers consist of monomer units held together by _____________ bonds
- covalent hydrogen
RNA contains the sugar _________
- ribose
DNA contains the sugar __________
- 2’-deoxyribose
The connection between monomer units is through a __________ group
- phosphate
The link between the two monomers/nucleotides is known as a _________________
- phosphodiester link/bond
The actual functional unit on a DNA/RNA molecule is the _____________
- heteropolymers, or nitrogenous bases
Two categories of heterolytic/nitrogenous bases
- purines
2. pyrimidines
____ contains the bases A, G, C, T
- DNA
____ contains the bases A, G, C, U
- RNA
adenine and guanine are ____________ (purines/pyrimidines)
- purines
cytosine, thymine, and uracil are ___________ (purines/pyrimidines)
- pyrimidines
The molecular components of nucleotides consist of __________, ________ and ______
- Nitrogenous bases
- Pentose Sugar
- Phosphate
RNA contains a different sugar from DNA, so its predominant form is a ______ strand that can intertwine or _____ to make secondary and primary structures
- single
- fold
DNA is made in a predominantly ________ form in antiparallel complementary strands.
- double helix
The inside portion of DNA has ________ (hydrophylic/hydrophobic) regions
- hydrophobic (nonpolar) regions
The exterior portion of DNA has ________ (hydrophylic/hydrophobic) regions
- hydrophylic (negative) regions
The function of DNA
- store genetic information and use it to build diff types of proteins
- to pass the genetic information to offspring
The function of RNA
- to transcribe the info in DNA to a form that can be understood and read by the cell
- to form proteins in ribosomes (protein synthesis)
On RNA, or ribose sugar the ___ carbon contains a ______ (hydrogen/hydroxyl) group
- 2’
- hydroxyl
On DNA, or deoxyribose sugar the ___ carbon contains a ______ (hydrogen/hydroxyl) group
- 2’
- hydrogen
The lack of the _____ group on the DNA sugar makes it more stable due to its resistance of hydrolysis
- hydroxyl
Nucleic acids have monomers/nucleotides linked together by bonds known as ___________ linkages
- 3’ -> 5’ phosphodiester
Nucleic acids backbone consists of _________, but do not include _____
- repeating sugar, phosphate units
- bases
The bases are attached to carbon __ of each sugar molecule and unlike the backbone which remains constant and unchanged, _____ from nucleotide to nucleotide
- 1’
- varies
Purines structures are _______
- 2 fused rings
Pyrimidine structures are ______
- a single ring
In DNA the pyrimidines are:
- cytosine and thymine
In RNA the pyrimidines are:
- cytosine and uracil
The function of nitrogenous bases
- to form the double helix bond
- vary from nucleotide to nucleotide, thus are responsible for determining the genetic code
A _______ is a linear polymer of monomers called nucleotides
- nucleic acid
A _____ consists of a sugar molecule and a base
- nucleoside
A nucleoside is a sugar molecule attached by a ________ bond to a base
- B-glycosidic bond
Adenosine, Guanosine ,Cytidine, and Uridine are the _______ (nucleotides/nucleosides) in _____ (DNA/RNA)
- nucleosides
- RNA
Deoxyadenosine, Deoxyguanosine ,Deoxycytidine, and Thymidine are the _______ (nucleotides/nucleosides) in _____ (DNA/RNA)
- nucleosides
- DNA
A ______ contains a sugar molecule, base and at least one phosphate group attached to the __ carbon
- nucleotide
(a nucleoside with a phosphate group) - 5’
Deoxyadenylate, Deoxyguanylate ,Deoxycytidylate, and Thymidylate are the _______ (nucleotides/nucleosides) in _____ (DNA/RNA)
- nucleotides
- DNA
Adenylate, Guanylate ,Cytidylate, and Uridylate are the _______ (nucleotides/nucleosides) in _____ (DNA/RNA)
- nucleotides
- RNA
DNA molecules are written in the _______ direction.
- 5’ to 3’
The 5’ end of a DNA molecule has a ______ group and the 3 end of a DNA molecule has a ______ group
- phosphate group
- hydroxyl (-OH)
Complementary DNA bonds between A,G,C,T, U
A=T, or U
C=G
The base group lies ____ the plane of the sugar group
- above
Rotation about the glycosidic bond results in syn and anti configurations where ____ configuration is favored
- anti
______ do not form syn configurations due to steric hinderance
- pyrmidines
____ is a phosphate acceptor/donor in intermediary energy metabolism
- ATP
____ promotes protein synthesis and signal transduction
- GTP
____ promotes membrane and storage lipid synthesis
- CTP
____ promotes carbohydrate synthesis and degredation
- UTP
Central Dogma of molecular biology
DNA(replication DNA->DNA)——-(transcription)–>RNA—–(translation)—->proteins—–(expression)—->traits
________ showed that DNA transferred from a virus to bacterium contains sufficient information to direct the synthesis of new viruses.
- Hershey and Chase
_______ Analyzed the Composition of DNA from Several Species
- Erwin Chargaff
Chargaffs rules
- The base composition of DNA varies from one species to the next.
- DNA specimens from different tissues of the same organism have the same base composition.
- The base composition of DNA in a given species does not change with age, nutritional state, or environment.
In all cellular DNA molecules . . . - [A] = [T] and [G] = [C]
______ Propose a New Model for DNA Structure
- Watson and Crick
_____ fiber diffraction pattern of DNA
- Rosalind Franklin’s
Double helix is ______ nm in diameter.
- 2.4
The double helix forms major and minor _____
- grooves
Helices are ______ in the way they turn.
It makes one complete turn every ___ nm.
- right hand (turn clockwise from each end)
- 3.4 nm
Functions of the major groove in DNA
- Recognition sites for several transcription initiation factors.
- Specific domains of initiation factors lie in major groove.
- Promote separation of DNA strands.
Functions of the minor groove in DNA
- Often bind smaller (non-protein) ligands which then can have several effects:
- Inhibits some cancers.
- Inhibits topoisomerases.
- Antimicrobial activity.
4 Stabilizing forces in DNA
- Hydrogen Bonds between base pairs
- Hydrophobic interactiosn between bases and water
- Van der Waals Forces
- Electrostatic Interactions
There are ___ hydrogen bonds between AT pairs and ____ hydrogen bonds between CG pairs
- two
- three
___ pairs separate easier than __ pairs
- AT
- CG
In _____ CG rich regions rotate about the glycosidic bond and take syn orientation. Since C bases cant form syn the H bonds hold and create a loop in the backbone.
- Z DNA
_______ DNA is a cross like DNA structure that form when DNA contains a palindrome
- cruciform, or double hairpin
A _____ is a base sequence in DNA that provides the same information when read in either the forward or reverse directions.
- palindrome (inverted repeats)
______ DNA is when the DNA and associated protein coil upon itself several times (beyond the normal helix structure).
- supercoiled DNA
Function of supercoiled DNA
- Compacts DNA to occupy less space.
- Inaccessible: i.e. prevents replication & transcription.
- Protects DNA when not being replicated or transcribed
Four main types of RNA’s
- tRNA (transfer)
- mRNA (messenger)
- rRNA (ribosomal)
- snRNA (small nuclear)
Function of tRNA
- translation (protein synthesis)
- Carry (transfer) amino acids to ribosome for assembly into polypeptides
- Often described as an “adaptor molecule”.
Function of rRNA
- structural elements of ribosomes consisting of about 60% of RNA
A _____, or DNA, is the total genetic information possessed by an individual organism
- genome
A _______, or RNA, is the complete set of RNA molecules produced by a cell, tissue, or organism under specific physiological conditions
- Transcriptome
A ________, or protein, is the complete set of protein molecules produced by a cell, tissue, or organism under specific physiological conditions
- protein
A ______ or metabolites and macromolecules, is the complete set of organic metabolites (sugars, lipids, amino acids) and macromolecules produced by a cell, tissue, or organism under specific physiological conditions
- metabolome