Lab 4B Flashcards
In a nucleoside monophosphate, the base is
connected to the __________carbon in the sugar
and the phosphate group is connected to the
_________ in the sugar.
1’ Carbon
5’ Carbon
The backbone of a DNA contains?
The phosphate group and the 5 Carbon sugar
What type of bonds holds nucleotides together?
Phosphodiester bonds.
What type of bond holds complementary base pairs together?
Hydrogen bonds.
The elements _______ and ___________ and some other elements we have
not covered are electronegative. What does that mean?
The elements Oxygen and Nitrogen are electronegative.
Electronegative elements can pull electrons off other elements that they are bonded to.
Because water is polar and contains H’s
that are __________________ in charge, it
can form hydrogen bonds with another
water molecule; these bonds are weak and
can be disrupted by boiling
Hydrogen is water is slightly positive.
The oxygen is slightly negative.
Hydrogen Donor?
Hydrogen Acceptor?
When Hydrogen is being donated to a hydrogen bond it is considered a donor.
When hydrogen is accepted by something more electronegative, it is considered an acceptor.
Why do purines and pyrimidines base pair with each other?
This allows the DNA backbone to remain stronger and neither bulge nor constrict.
Constrictions and bulged weakens the backbone.
What do phosphodiester bonds form between, and what do they do?
Phosphodiester bonds form between nucleotides (Sugar and phosphate group), and they increase the strength of the backbone.
Two purines being paired creates a?
Two Pyrimidines paired together to create a?
Bulge.
Constriction.
What does a glycosidic bond connect?
The glycosidic bond connects a sugar to the base.
It keeps the chemical letters from falling off the sugar.
What allows the DNA bases to be accessible when needed?
Hydrogen bonds.
They form in the bases between the strains. (A-T, C-G)
The backbone consists of a ____________ and a
________________. These are connected by
phosphodiester bonds.
5 Carbon sugar
Phosphate Group.
The ends of DNA or RNA strands are 5’ and 3’,
whereas, the ends of a peptide are _________ and
___________.
Amino end or N-Terminus (Left side).
Carboxy end or C-Terminus (Right side).
The phosphodiester linkage is
between the ________carbon on
one deoxyribose and the
________ carbon on another
deoxyribose.
5’
3’
The phosphate groups give the
backbone full negative charges
so that each nucleotide in the
backbone has
______________full negative
charge and the one on the
_____________end has 2.
Nucleotide in the backbone has 1 Negative charge.
5’ End has two negative charges.
How can you identify the 5’ end and the 3’ end?
The 5’ end has a phosphate group sticking out, while the 3’ end has a hydroxyl.
Ester linkage vs Diester Linkage vs Phosphodiester linkage.
An Ester linkage is a carbon double bonded to an oxygen, and single bonded to another oxygen. R-C-OR
A Diester Linkage is two ester linkages.
In a phosphodiester linkage, a phosphate replaces the carbon (In the Diester linkage).
We saw the phosphodiester linkage in the substance _________________ located in the
__________________.
Teichoic Acid.
Cell wall.
Phosphodiester linkage is found in gram-positive bacteria.
Bacillus Anthracis is a gram positive bacteria.
How do you make a phosphodiester bond?
The bond is dependent on the electronegativity
of oxygen to create an unequal distribution of charge,
allowing an O to be attracted to a P.
This involves partial charges.
Making Phosphodiester bonds is an endergonic reaction.
Template strand or parent strand
This is the old strand. It is read from the 3-5’ Direction.
Daughter strand
The new strand is made from the template strand. It is read in the 5-3’ Direction.
To add a nucleotide, DNA polymerases use a nucleoside ________________;
breaking off of the diphosphate from the nucleoside __________________
and subsequent breakdown of the diphosphate is exergonic; the making of
the phosphodiester bond is endergonic. The exergonic reactions drive the
endergonic one.
Triphosphate.
Nucleoside Triphosphate.
The process of making nucleic acid is endergonic.
The __________________ in the
nucleoside _______________is
slightly positive because it is
surrounded by _______________,
which are _______________. The
triphosphate is connected to the
___________ carbon of deoxyribose.
Phosphorus
Triphosphate
Oxygen
Electro-negative
5’
The _________________
on the __________ carbon
of a nucleoside
monophosphate has a
slightly _______________
which is attracted to the
slightly _____________
_______________ in the
first phosphate group in a
nucleoside triphosphate.
Oxygen
3’
Negative charge
Positive
Phosphorus
Antiparallel nature of DNA?
Strands of nucleic acid that base pair are upside down in relation to one another and the bases are turned inward.
Replication: DNA
Transcription: DNA & RNA
Translation: RNA & RNA
The antiparallel nature of DNA is important in allowing base pairing to occur between two complementary strands.
Base pairing in Transcription?
In transcription, base pairing allows
the mRNA to be made from the complementary DNA strand in a gene.
The base pairing between DNA and RNA in transcription is temporary as the mRNA is released from the DNA in bacteria as the mRNA is translated.
[Simultaneuos gene transcription & Translation in bacteria]
Base pairing in Translation?
In terms of translation, the anticodon on the tRNA is
complementary to the codon on the mRNA.
What is Intramolecular Base Pairing?
Base pairing within a strand of tRNA.
This gives the tRNA a cloverleaf shape.
What is Intermolecular Base pairing?
Base pairing between tRNA and mRNA, or between mRNA and DNA.
The ____ on the _____ encodes for Amino acid.
codon.
mRNA.
What is the sugar in DNA?
What is the sugar in RNA?
Deoxyribose
Ribose
