LESSON 2 - PRELIM Flashcards
heredity
Gregor Mendel
flies, linkage
Thomas Hunt Morgan
1928: transformation and mice
Frederick Griffith
1944: DNA as the transforming agent
Oswald Theodore Avery, Colin MacLeod and Maclyn
McCarty
late 40’s-early 50’s: base pairing=AT
CG
Erwin Chargaff
(1952: DNA is not a
protein
Alfred Hershey-Martha Chase
1953: chemical structure of DNA –
secondary structure: double-helix
Watson and Crick
mid 1950’s: DNA Replication details:
semi-conservative replication model
Meselson-Stahl
__________ in 1869
Isolated what he called nuclein from the nuclei of pus
cells
Nuclein was shown to have acidic properties, hence
it became called nucleic acid
Friedrich Miescher
structure in the cell nucleus which is the visible
carrier of genetic information
Chromosomes
portion of a chromosome that controlled a specific
inheritable trait
Genes
carries information which directs the process of
protein synthesis
within the nucleic acids are the codes needed for
transcription and translation of proteins
Nucleic Acids
________ (entire set of genes of an organism) size is based
on number of nucleotide pairs present
Genome
Among eukaryotes, there is no
consistent relationship on the C-value (DNA content of
the genome) and the metabolic, developmental, or
behavioural complexity of the organism
C-value paradox
Within the nucleus, __________are located (as pairs)
chromosomes
___________ are tied together (by protein centromere)
Chromosomes
(Telomeres)
Ends of the chromosome
(genes are specific
portions of chromosome coding for a protein which
functions in various phase)
Within the chromosome are genes
(DNA: double-helix
molecule containing base pair)
In the genes are nucleic acids
Composition of Nucleic Acids
Nucleic Acids (repeating series of nucleotide)
Polymers (polynucleotides)
Parts of Nucleotide
A five-membered ring monosaccharide
A nitrogen-containing cyclic compound (nitrogenous
bases)
A phosphate group
Types of Nucleic Acids
DNA (genetic material – doesn’t function without
RNA)
RNA
Sugars
2-deoxyribose (for DNA)
o 5th carbon – phosphate group
o 3rd – next nucleotide attached
Ribose (for RNA)
o 2nd carbon - oxygen
Nitrogenous Base
Purines (2)
o Contains two-fused N-containing ring
Adenine (A)
Guanine (G)
Pyrimidines (3)
o Has one nitrogen-containing ring
Cytosine (C)
Thymine (T)
Uracil (U)
Sugar + Base =
Nucleoside
Adenine + (deoxy)ribose =
(deoxy)adenosine
Guanine + (deoxy)ribose =
(deoxy)guanosine
Cytosine + (deoxy)ribose =
(deoxy)cytidine
Thymine + deoxyribose =
deoxythymidine
Uracil + ribose
uridine
nucleoside formed after combination of
adenine with ribose
Adenosine
NUCLEOSIDE + Phosphate =
NUCLEOTIDE (Tide labada)
Are the building blocks of nucleic acids
Monomers of the DNA and RNA polymers
Is a 5’-monophoshpate ester of a nucleoside
Are named by adding 5’-monophosphate at the end
of the name of the nucleoside
NUCLEOTIDE
Can add additional phosphate groups to form
diphosphate or triphosphate esters (necessary to
produce energy needed in transcription, translation
and repli)
Nucleotides
Bases Deoxyribonucleosides Deoxyribonucleotides
Adenine (A)
Deoxyadenosine Deoxyadenosine 5’-
Monophosphate
(dAMP)
Bases Deoxyribonucleosides Deoxyribonucleotides
Guanine
(G)
Deoxyguanosine Deoxyguanosine 5’-
Monophosphate
(dGMP)
Bases Deoxyribonucleosides Deoxyribonucleotides
Cytosine
(C)
Deoxycytidine Deoxycytidine 5’-
Monophosphate
(dCMP)
Bases Deoxyribonucleosides Deoxyribonucleotides
Thymine
(T)
Deoxythymidine Deoxythymidine 5’-
Monophosphate
(dTMP)
Bases
Ribonucleosides Ribonucleotides
Adenine (A)
Adenine (A) Adenosine Adenosine 5’-
Monophosphate
(AMP)
Bases
Ribonucleosides Ribonucleotides
Guanine (G)
Guanine (G) Guanosine Guanosine 5’-
Monophosphate
(GMP)
Bases
Ribonucleosides Ribonucleotides
Cytosine (C)
Cytosine (C) Cytidne Cytidine 5’-
Monophosphate
(CMP)
Bases
Ribonucleosides Ribonucleotides
Uracil (U)
Uracil (U) Uridine Uridine 5’-
Monophosphate
(UMP)
the repeating sequence of nucleotides form its
primary structure (forming alternating ribose and
phosphate backbone – providing structural stability)
Primary Structure (from polymerization of monomers)
Based on:
o Chargaff rule
Secondary Structure
Obtained by Rosalind Franklin and Maurice
Wilkins
Diagonal image: helical structure of DNA
X-ray diffraction photographs
A, T, G, and C (complimentary) are present
in equimolar quantities (refers to similarity in
molar concentration in DNA hydrolysis;
equal concentration)
If this 2 molecules are placed together, they
form hydrogen bonds
Similar molar concentration upon DNA
hydrolysis
Chargaff rule
o The 2 (single strand of DNA) polynucleotide
chains run in opposite directions
o One 5’ – OH and one 3’ – OH terminal
o Bases are hydrophobic (non polar, tucked
inside)
o Sugar phosphate backbone is hydrophilic (polar,
exposed to environment)
Double helix
Basic protein to w/c the DNA is coiled around
Higher Structure