the structure of DNA, nucleotides

1. New Seating Chart

2. Semester 2 Preview
 Genetics
◦ DNA
◦ Gene expression and
protein synthesis
◦ Mutations
◦ Creation of sex cells
(gametes)
◦ Inheritance of traits
◦ biotechnology
 Evolution
◦ Gene pools
◦ Sources of variation
◦ Natural selection
◦ Evidence for evolution
◦ Adaptations
◦ Human impacts on
gene pools
• Classification of life
– Kingdom Animalia
• Nervous systems
– Kingdom Plantae
• Vascular systems
• Plant reproduction

3. https://www.youtube.com/watch?v=EzEr23XJwFY
https://www.twig-world.com/film/genetic-modification-1063/

4. So what is a GMO and why are
they controversial?

5. Quick Check
Where is the DNA in a
eukaryotic cell?

6. 1-4-17
Objective
create a model of a DNA
molecule and correctly
identify each component

7. As always…
 Key concepts are underlined
 Vocab is in green

8. DNA
Structure

9. Big Idea # 1
 DNA is a type of
nucleic acid made
up of repeating
units called
nucleotides
1 nucleotide

10. Remember…
 Nucleotides are like building
blocks
 A long chain stacked together
makes a DNA molecule
Like 1
nucleotide
Many
nucleotides
linked
together =
DNA

11. Big Idea # 2
 Nucleotides are
made up of 3
parts

12. 1. sugar called deoxyribose
2. phosphate group
3. nitrogen base
Deoxyribose
Draw along with
me in your
notebook

13. Quick Check
What
observations
can you
make about
this model of
DNA?

14.  The deoxyribose sugar
and the phosphate are
ALWAYS THE SAME
 There are 4 KINDS of
nitrogen bases:
– Adenine (A)
– Guanine (G)
– Cytosine (C)
– Thymine (T)
but…

15. Quick Check
 In your notebook
Draw an ADENINE
NUCLEOTIDE pairing with
the one you already drew

16. Big Idea #3
 In DNA:
– A always pairs with T
– C always pairs with G

17.  A and T form 2 hydrogen bonds between
them

18.  C and G form 3 hydrogen bonds between
them

19. Quick Check
What observations can you
make about the 4 nitrogen
bases in DNA?

20. Big idea #4
 DNA is a double helix
 Double - 2 strands
 Helix - twisted

21.  The 2 strands of DNA are
COMPLIMENTARY to each other

22. For your assignment:
 Color the sugar deoxyribose BLUE
 Color the phosphate group PURPLE
 Color the Adenine RED
 Color the Thymine YELLOW
 Color the Cytosine ORANGE
 Color the Guanine GREEN
 Answer the questions on a piece of binder
paper and build the molecule
 When you are done, bring your molecule
to the wall and join it to the others