DNADNA
Name the organelle and give its function.
Animal Plant
Nucleus
Ribosome
Endoplasmic Reticulum: aids in processing carbohydrates, lipids and proteins for export from the cell
Endoplasmic Reticulum
Golgi Body
Nucleus: control body of the cell; contains the genetic material (DNA)Golgi Aparatus: modifies, sorts, and packages materials from the ER for storage in the cell or secretion outside the cell
Ribosome: site where proteins are made
What is located in the nucleus?
What type of organic compound is DNA?
What is the monomer of DNA?
What does the DNA of all these organisms have in common?
They all share a universal genetic code.
The History of Heredity
Why am I so gorgeous?
Gregor Mendel
Gregor Mendel determined that traits were passed from generation to generation.
But, I haven’tfigured out
how thishappens
What was this substance called?
DNA
Rosalind Franklin &Maurice Wilkins
Franklin and Wilkins used x-ray to discover that DNA was a double helix.
Watson and CrickWatson & 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.
Erwin Chargaff
Chargoff discovered that DNA contains the same amount of adenosine as thymine and the same amount of cytosine as guanine.
A A A
T T T C C
C C
G GG G
DNA is a Nucleic AcidWhat is a nucleic acid?
Nucleic acids are one of the major organic compounds.
Nucleic acids contain C, H, N, O, P
Are made up of nucleotide monomers
Double helix shape
Store genetic information
Help make proteins
Examples: DNA & RNA
sugar
phosphate
nitrogen base
A NUCLEOTIDE
H
H2
H H
H3
HH H
H
H
O
O
O
C C
C
N
N
PO
O
O
C
C
C C
C
O
OO
C
C
1.
2.
3.
1.
2.
3.
1. Phosphate Group2. 5-Carbon Sugar
(Dexoyribose or Ribose)3. Nitrogen Base
1. Phosphate Group
2. 5-Carbon Sugar(Dexoyribose or Ribose)
3. Nitrogen Base
Nucleotides, too
NucleotidesThere are four nitrogen bases making up four different nucleotides.
Adenine
Guanine
Thymine
CytosinePyrimidines
PurinesA
C
G
T
N base
Chargaff’s Base Pair Rules
Adenine always bonds with thymine. A = T
Guanine always bonds with Cytosine. G C
The lines between the bases represent hydrogen bonds
A
CG
T
C
G
A
A
T
G
Nucleotide
PS
N-b
Pairing DNA NucleotidesWhat is a nucleotide?
Rule
A to
C to
T
G
What is the base pairing rule?What would be the complementary nucleotide pairing?
3’End
3’End 5’End
5’End
DN
A D
OU
BL
E H
EL
IX
ladder shaped molecule
Purpose of DNA
Why do we have DNA?
For what does it code?
What actually makes you look the way you do?
Remember that the monomer for proteins
is amino acids!
DNA Codes for Amino Acids
The nitrogen bases in DNA code for amino acids.
A triplet of nitrogen bases codes for one amino acid.
The triplet is called a codon.
What is RNA?
DNA must have a “helper” molecule.
RNA stands for RiboNucleic Acid
RNA is a single stranded nucleic acid made up of monomers called nucleotides
sugar
phosphate
nitrogen base
A
B
C
RNA Nucleotides
A - Sugar (ribose)
B - Phosphate
C - Nitrogen base
sugar
phosphate
nitrogen base
Name the parts of the nucleotide.
Rules for Base Pairing
Cytosine pairs with Guanine
Adenine pairs with Uracil
Notice that RNA has Uracil (not thymine)
A = U
C = G
Rules for Base Pairing
C = G
A = U
3’ DNA strand
5’ DNA strandRNA strand
C
A
T
G
G
U
C
A
What is the function of RNA?
Carries DNA’s message code
Helps make protein
Types of RNAMessenger RNA (mRNA)Transfer RNA (tRNA)Ribosomal RNA (rRNA)
Phosphate Group
Nitrogen Base
Sugar
(ribose)
RNA
Identify the parts of the RNA strand.
DNA RNA
Sugar is deoxyribose
Sugar is ribose
Adenine base is present
Cytosine base is present
√
√
√ √
√ √
Comparing DNA & RNA
DNA RNA
Guanine base is present
Thymine base is present
Uracil base is present
Shape is double helix
√ √
√
√
√
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
√ √
√ √
√
√
√
Comparing DNA & RNA