Objective: Understand the structure of DNA
Key words: Nucleic Acids, DNA, RNA, nucleotides, nitrogen bases.
Do Now: Compare and contrast the molecules below.
How are all of them similar? How does Nucleic Acid differ?
Glucose
Nucleic Acid
Lipid
Amino- acid
Objective: Understand the structure of DNA
Key words: Nucleic Acids, DNA, RNA, nucleotides, nitrogen bases.
Where do you find Nucleic Acids in a cell?
Objective: Understand the structure of DNA
Key words: Nucleic Acids, DNA, RNA, nucleotides, nitrogen bases.
Where do you find Nucleic Acids in a cell?
Objective: Understand the structure of DNA
Key words: Nucleic Acids, DNA, RNA, nucleotides, nitrogen bases.
How is the structure of a Nucleic Acid?
What is the pattern?
Objective: Understand the structure of DNA
Key words: Nucleic Acids, DNA, RNA, nucleotides, nitrogen bases.
DNA structure of double helix
Objective: Understand the structure of DNA
Key words: Nucleic Acids, DNA, RNA, nucleotides, nitrogen bases.
Chromosome
Nucleosome
DNA
double
helix
Coils
Supercoils
Histones
Objective: Understand the structure of DNA
Key words: Nucleic Acids, DNA, RNA, nucleotides, nitrogen bases.
Structure of DNA
Nucleotide
Hydrogen
bonds
Sugar-phosphate
backbone
Key
Adenine (A)
Thymine (T)
Cytosine (C)
Guanine (G)
DNA is made up of repeating unit of nucleotides.
Objective: Understand the structure of DNA
Key words: Nucleic Acids, DNA, RNA, nucleotides, nitrogen bases.
Watson & Crick
Watson and Crick discovered the double helix structure of DNA in 1953
Objective: Understand the structure of DNA
Key words: Nucleic Acids, DNA, RNA, nucleotides, nitrogen bases.
What is a nucleotide?
1. What kind of molecules is a nucleotide? (Organic or inorganic)
Organic molecule
_______________________________
2. How do you know:
It is made of carbon, hydrogen and oxygen
a._______________________________________
Carbon is the main element
b. _______________________________________
It is a large and complex molecule
c. _______________________________________
3. What are the THREE common parts of a nucleotide.
Deoxyribose or sugar
a. _____________________________________________
Phosphate group
b. _____________________________________________
Nitrogen base
c. ______________________________________________
4. What is the ONE part of a nucleotide that differs among the four DIFFERENT
nucleotides? Nitrogen base
___________________________________________________
5. List the FOUR different kinds of nitrogen bases.
a ____________________________________________
(A) Adenine
b____________________________________________
(G) Guanine
c _____________________________________________
(C) Cytosine
d _____________________________________________
(T) Thymine
Objective: Understand How Nitrogen Bases pair in DNA
Key words: Nitrogen Bases, DNA, Adenine, Cytosine, Guanine, Thymine
Do Now: List 3 things you learned about the structure of Nucleic Acids
Objective: Understand How Nitrogen Bases pair in DNA
Key words: Nitrogen Bases, DNA, Adenine, Cytosine, Guanine, Thymine
6. Explain WHERE the nucleotide molecules connect to each other.
• Phosphate group connects to _____________________
deoxyribose (sugar)
nitrogen base
• Nitrogen base connects to_________________________
Objective: Understand How Nitrogen Bases pair in DNA
Key words: Nitrogen Bases, DNA, Adenine, Cytosine, Guanine, Thymine
A real DNA molecule consists of THOUSAND of pairs of nucleotides.
7. What is the pairing arrangement of nitrogen bases?
(T) Thymine pairs with ____________________________
(A) Adenine
___________________
(G) Guanine pairs with_____________________________
(C) Cytosine
and _______________
Objective: Understand How Nitrogen Bases pair in DNA
Key words: Nitrogen Bases, DNA, Adenine, Cytosine, Guanine, Thymine
8.Are there always going to be an EQUAL number of adenine and thymine
nucleotides in a molecule? Yes
Why? Because Adenine always pairs to Thymine
Are there always going to be an EQUAL number of Guanine and Cytosine
nucleotides in a molecule? Yes
Why Because Guanine always pairs to Cytosine
Objective: Understand How Nitrogen Bases pair in DNA
Key words: Nitrogen Bases, DNA, Adenine, Cytosine, Guanine, Thymine
9. Scientists abbreviate the nitrogen bases by using the first letter of each base. So,
T
Cytosine
A always binds to _____________
Guanine always binds to ______________________
C
Guanine
G always binds to _____________
Cytosine always binds to ______________________
G
C always binds to _____________
Thymine always binds to ______________________
Adenine
A
T always binds to _____________
Adenine always binds to ______________________
Thymine
10. Pair the missing bases on the DNA molecules.
a) A – T – A – A – G – C – T – A - G
__________________________________
T–A –T –T – C–G– A– T–C
b) C – C – G – T – A – A – C – G – A
__________________________________
G–G–C–A–T–T–G– C-T
c) A – T – A – C – T – A – G – C – A
__________________________________
T–A–T–G–A–T–C–G-T
d) G – C – T – A – C - A - G – A – C
__________________________________
C–G–A–T–G–T–C–T–G
DNA replication
New strand
Original
strand
DNA
polymerase
Growth
DNA
polymerase
Growth
Replication
fork
Replication
fork
New strand
Original
strand
Objective: Understand How Nitrogen Bases pair in DNA
Key words: Nitrogen Bases, DNA, Adenine, Cytosine, Guanine, Thymine
10. What is the function of the DNA?
To store and transmit the genetic information from one
Generation of an organism to the next
11. What is the structure of DNA?
Double helix