12/15/15
Date:
12/15/15
Topic:
DNA Modeling 2
Page # ___
Date:
12/15/15
Topic:
DNA Modeling 2
Page # ___
Today in Room 326/311…
HW: DNA worksheet
CONTENT OBJ: SW identify the parts of a DNA molecule and
build one using kinex
LANG. OBJ: SW write vocabulary notes in journal; discuss in
pairs to create DNA model
AGENDA:
AS: Choose science fair project – 5 min
Class votes/chooses projects – 15 min
Groups fill out Info Sheet- 15 min
DNA notes – 20 min
DNA Modeling – 20 min
Science Fair Projects
New list
Pick your top 3 choices
You will have 3 votes
Projects with top 4 votes will be chosen
Students will pick each project as their name is
called
Early Steps
1. Exchange Contact Information!!
Phone numbers and email … go!
2. Materials List
What will you need in order to complete project?
Write down everything.
Put a *star* next to materials you are absolutely sure
you can’t get yourself.
3. Researchable Questions – need one per person
Researchable Questions
Provide background research
Example: Science fair question“Which paper towel product holds the most liquid?”
Questions: “What are the ingredients of each company’s
paper towel?”
“How do the sales differ between each product (cost and
amount sold)?”
“What properties of water makes it go onto the towel?”
– Research iso/hypo/hypertonic solutions and the
cohesion/adhesion
Turn in Form
Fill out Science Fair Form
with all this info to be turned in
DNA
How can you draw DNA?
Make a sketch in your journal.
Volunteers to draw?
Where is DNA?
Recall… how is DNA related to chromosomes?
Structure of DNA
What does DNA stand for?
D: Deoxyribose
(“se” is dropped in name)
N: Nucleic
A: Acid
“Deoxyribo nucleic acid”
DNA Vocab*
DNA shape = Double helix
Each helix is known as the
“sugar-phosphate backbone”
Made of sugar & phosphate!
Deoxyribose = 5 Carbon sugar
Phosphate group
Holds nitrogenous bases
in place
4 types: A, T, C, G
Draw/Label this 
DNA Structure
*DNA is made of nucleotides
- phosphate group*
- 5 carbon sugar*
- nitrogenous base*
They are arranged in a
specific order 
known as “directionality”
Vocab Review
4 Biological Molecules:
Carbs, Proteins, Lipids, &
NUCLEIC ACIDS!
Nucleic acid = DNA and RNA
Nucleic acids are made of nucleotides
Nucleotides are made of sugar, phosphate, and a
nitrogenous base (A, T, C, G)
DNA Directionality
DNA backbone is arranged with a
3’ (prime) end and a 5’ (prime) end*
The two strands of DNA are
antiparallel*
(run in opposite directions)
Also known as complementary
strands*
Base Pairing*
The four nitrogenous bases
(A, T, C, G) interact to hold the
double helix in place
A = Adenine
Pair together
T = Thymine
C = Cytosine
G = Guanine
Pair together
Bases are joined by
hydrogen bonds
Base Pairing*
Purines
Adenine (A)
How many
hydrogen bonds
in each pair?*
Guanine (G)
2
bond
s
Have TWO rings (but short name)
Pyrimidines
Thymine (T)
Cytosine (C)
Have ONE ring (but long name)
3
bond
s
Chargaff’s
Rule*
amount of A = amount of T
amount of C = amount of G
DNA Modeling
Quickly make a DNA model again
Make sure the sugar-phosphate
backbone is all GREY
A = white
T = black
G = green
C = grey
Orange bond
( = 2 bonds)
Grey bond
(= 3 bonds)
Homework
DNA worksheet