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Teacher Notes
This PPT was revised October 25, 2005.
This PPT introduces scientist/history of
DNA, DNA structure and RNA structure.
There is a DNA Structure handout for this
PPT. The DNA Scientists portion can be
done using the book and review with this
PPT.
The Structure of DNA
Should auld acquaintance be forgot,
And Auld Lang Syne!
And Auld Lang Syne!
Name
the
organelle
give
its
Ribosome:
Endoplasmic
Nucleus:
Golgi
Aparatus:
control
site
Reticulum:
where
modifies,
body proteins
ofand
aids
the
sorts,
cell;
inare
processing
and
contains
made
packages
the
carbohydrates,
genetic
materials
material
from the
lipids
(DNA)
ERand
for storage
proteinsinfor
the
export
cell or
function.
from the cell
secretion
outside the cell
Endoplasmic Reticulum
Nucleus
Golgi Body
Animal
Ribosome
Plant
And Auld Lang Syne!
What is located in the nucleus?
What type of organic compound is DNA?
What is the monomer of DNA?
And Auld Lang Syne!
What does the DNA of all these
organisms have in common?
They all share a universal
genetic code.
And Auld Lang Syne!
What is the name of these monomers?
H
H
N
amine group
C
O
C
OH
R
H
carboxyl group
variable R group
H
amine group
H
N
H
C
R
O
C
carboxyl group
OH
To what organic compound group do
they belong?
And Auld Lang Syne!
What does the chain of amino acids
represent?
Threonine
Asparagine
Arginine
Glycine
Proline
Proline
Glycine
Polypeptide Chain – A Protein
Alanine
History of Heredity
Why am I so
gorgeous?
Gregor Mendel
Gregor Mendel
determined that
traits were
passed from
generation to
generation.
But, I haven’t
figured out
how this
happens
Frederick Griffith
Griffith was working on a vaccine for
Streptococcus pneumoniae
He worked with 2 strains of the
bacteria:
Smooth capsule that causes disease
Rough capsule that does not cause
disease
Frederick Griffith
He added these bacteria strains,
some dead and some living, to lab
rats.
These are his results:
Frederick Griffith
Live
Smooth
Bacteria
Live
Rough
Bacteria
Dead
Smooth
Bacteria
Live R+
dead S
Bacteria
Griffith Proved:
That somehow the dead bacteria
have passed their disease-causing
substance to the harmless, living
bacteria.
Griffith discovered a factor that could
transform harmless bacteria into
disease-causing bacteria
What was this substance called?
DNA
Oswald Avery
Avery’s team determined that genes
are composed of DNA
Erwin Chargaff
Chargoff discovered that DNA has the
same amount of adenosine as thymine
and the same amount of cytosine as
guanine. A = T and G = C
AA
A
A
A AA
T
TTT
TT T
C
CC
G
G G
Rosalind Franklin &
Maurice Wilkins
Franklin and
Wilkins used
x-ray to
discover that
DNA was a
double helix.
Watson and Crick
Watson & Crick won a Nobel Prize for
discovering the structural model of
DNA.
They credited Wilkins
and Franklin.
Wilkins also got a
Nobel Prize but
Franklin did not.
Rosalind had passed
away and the Nobels
are not awarded
posthumously.
DNA is a Nucleic Acid
What is a nucleic acid?
Nucleic acids are one of the major
organic compounds.
Auld Lang Syne!
Nucleic acids contain
C, H, N, O, P
Are made up of
nucleotide monomers
Store genetic
information
Help make proteins
Examples: DNA &
RNA
sugar
nitrogen
base
phosphate
DeoxyriboNucleic Acid
DNA Structure
For what does DNA stand?
What is the monomer for nucleic acids?
What is the structure of this monomer?
nucleotide
phosphate
sugar
nitrogen base
PO4 (the 5’ end)
5
The numbers
N base
are the
4 Sugar 1
positions of
the carbons
3
2
DeoxyriboNucleic Acid
on the sugar.
(the 3’ end)
A NUCLEOTIDE
1. Phosphate Group
3. 5-Carbon
2.
Nitrogen Base
Sugar
2. 5-Carbon Sugar
1. Phosphate Group
(Dexoyribose or Ribose)
(Dexoyribose or Ribose)
3.
1.
3. Nitrogen Base
2.
O
O
P
O
3.
1.
2.
O
C H2
C H3
C
O
CH
HC
C H CH
HO H O
Nucleotides, too
O
C
CH
N
N
C
O
H
Nucleotides
There are four nitrogen bases making
up four different nucleotides.
Purines
Adenine
A
Guanine
G
N base
Pyrimidines
Thymine T
Cytosine C
Chargaff’s Base Pair Rules
Adenine always bonds with thymine.
Adenine (A) to Thymine (T)
A
T
The lines between the bases represent hydrogen bonds
G
C
Guanine always bonds with Cytosine.
Guanine (G) to Cytosine (C)
Pairing DNA Nucleotides
What would
is the
a nucleotide?
base
be the
pairing
complementary
rule?
nucleotide pairing?
Nucleotide
P
S
N-b
C
G
Rule
A
A to T
A
C to G
T
G
DNA DOUBLE HELIX
5’End
3’End
ladder
shaped
molecule
3’End
5’End
Purpose of DNA
Why do we have DNA?
DNA contains our genetic
codes
For what does it code?
for proteins
What actually makes you
look the way you do DNA or Proteins?
What is RNA?
RNA stands for
RiboNucleic Acid
DNA must have a
“helper” molecule.
RNA is a single
stranded nucleic acid
made up of monomers
called nucleotides
sugar
phosphate
nitrogen
base
RNA Nucleotides
A - Sugar (ribose)
B - Phosphate
C - Nitrogen base
sugar
nitrogen
base
phosphate
B
Name the parts of the nucleotide.
A
C
RNA
Identify the parts of the RNA strand.
Nitrogen Base
Sugar
(ribose)
Phosphate Group
Rules for Base Pairing
Cytosine pairs with Guanine
C = G
Adenine pairs with Uracil
A = U
Notice that RNA has Uracil
(not thymine)
Rules for Base Pairing
3’ DNA strand
C=G
C
G
A
U
G
C
T
A
A=U
RNA strand
5’ DNA strand
What is the function of RNA?
Carries DNA’s message code
Helps make protein
Types of RNA
Messenger RNA (mRNA)
Transfer RNA (tRNA)
Ribosomal RNA (rRNA)
Comparing DNA & RNA
DNA RNA
Sugar is deoxyribose
√
Sugar is ribose
√
Adenine base is present
√
√
Cytosine base is present
√
√
Comparing DNA & RNA
DNA
Guanine base is present
√
Thymine base is present
√
Uracil base is present
Shape is double helix
RNA
√
√
√
Comparing DNA & RNA
DNA RNA
Shape is single stranded
Located in nucleus
√
√
√
Located in cytoplasm
Stores genetic information
√
√
Comparing DNA & RNA
DNA RNA
Functions in protein synthesis √
√
Composed of nucleotides
√
√
Template for synthesis of
proteins
Transcribes the Template
√
More than one type
√
√
Works Cited