How DNA synthesis & protein synthesis happens

1. DNA and Protein Synthesis

2. Nucleic Acids

3. Nucleic Acids - Function
• Control the processes of
heredity by which cells and
organisms make proteins.

4. Nucleic Acids – Types
• DNA
–Deoxyribonucleic Acid
• RNA
–Ribonucleic Acid

5. As you know, DNA stands for….
DEOXYRIBONUCLEIC
ACID

6. Is DNA a monomer or polymer
50% 1. Monomer
50% 2. Polymer
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24

7. The monomer units of DNA are
known as….
NUCLEOTIDES

8. All nucleotides have three “parts” in
common. They all contain….
One of FOUR different
NITROGEN BASES
Phosphate Group
Sugar= Deoxyribose

9. PLEASE UNDERSTAND, A NUCLEOTIDE
IS A VERY COMPLEX STRUCTURE. IF WE
REPRESENTED ALL OF THE ATOMS, IT
WOULD LOOK LIKE THIS…

10. We will use our hands to represent a
nucleotide.
PHOSPHATE NITROGEN
BASE
SUGAR

11. The four different Nitrogen Bases for DNA
are abbreviated using the following letters….
A Adenine
T Thymine
G Guanine
C Cytosine

12. Using your two hands, please show how
you think two nucleotides will/should bond
together.
Did you put your hands like this???

13. In DNA, Adenine always pairs
with Thymine using two hydrogen
bonds.
A T

14. A AND T AT THE ATOMIC LEVEL

15. In DNA GUANINE always pairs with
CYTOSINE using three hydrogen
bonds.
G C

16. G AND C AT THE ATOMIC LEVEL

17. THE
ENTIRE
MOLECULE
AT THE
ATOMIC
LEVEL

18. Time to use your brain and
hands in order to review
nucleotide structure and type.
USING YOUR HAND, SHOW ME THYMINE
USING YOUR HAND SHOW ME ADENINE
SHOW ME CYTOSINE
SHOW ME HOW CYTOSINE AND THYMINE BOND
TO FORM A RUNG ON THE LADDER
THEY DON’T

19. OK
Now that you recognize
nucleotide type and structure, it’s
time to start building the polymer
from these monomers.

20. In order to make a molecule of DNA,
you would need to create many rungs
to the DNA ladder.
Look. Many Rungs.
Etc…

21. What part of the nucleotide alternates
to form the sides of the DNA ladder?
Sugar, Phosphate.
Sugar, Phosphate.
Sugar, Phosphate.
Etc…
Etc…

22. What makes up the
“RUNGS” of the ladder?
The Nitrogen
Bases

23. Go Ahead!
Stack your hands on top of your partner’s
hands building two rungs of the DNA
ladder.

24. TRY IT!!!

25. If you link enough nucleotides together,
the DNA molecule begins to take on
the characteristic shape known as the
Double Helix

26. Let’s make a candy version of
our DNA

27. Let’s Review First…
• Nucleic Acid
• Nucleotide
• DNA
• RNA
• Nitrogen Base
• Double Helix

28. Nucleic Acid – Structure
• Made up of a chain of Nucleotides
that contain
– Phosphate backbone
– Sugar
– Nitrogen base
• Guanine
• Cytosine
• Adenine
• Thymine (Found only in DNA)

29. Nucleic Acids

30. DNA

31. DNA
SUGAR
Phosphate

32. Let’s see how well you looked at the
diagram…regarding the nitrogen bases,
Adenine always bonds with which one?
1. Cytosine
2. Thymine
3. Guanine
4. Uracil
0% 0% 0% 0%
e
il
ne
e
in
c
in
ra
ni
ym
os
ua
U
yt
Th
G
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
C
21 22 23 24

33. DNA
SUGAR
Phosphate

34. Let’s make a candy version of
our DNA

35. Candy DNA
• Pipe cleaner for the form
• Red Twizzler = Deoxyribose
• Black Twizzler = Phosphate
• Colored Marshmallows = nitrogen bases

36. Candy DNA
• Colored Marshmallows = Nitrogen Bases
– Pink Marshmallow = Adenine
– Green Marshmallow = Thymine
– Yellow Marshmallow = Cytosine
– Orange Marshmallow = Guanine
• We’ll use toothpicks to join the nitrogen
bases to the sugar

37. Let’s Build

38. What actual structures make up the
sides of the ladder?
• Deoxyribose sugar
• Phosphate

39. What structures make up the
rungs?
• Nitrogen Bases

40. What do you notice about all the
DNA molecules in the room?
• They are all different!

41. DNA Replication
• 1.) DNA unzips
• 2.) Free nucleotides bond with open
complementary base pairs
• 3.) 2 new strands formed

43. Let’s review DNA

44. Let’s Build A Protein

45. Protein Synthesis
• It’s a process
– DNA -> RNA -> Amino Acids (Protein)

46. RNA
• Sugar is Ribose NOT
what…
• Has nitrogen base
Uracil instead of
Thymine
– Also contains the other
3 bases…what are
they?
• Only single stranded

47. RNA

48. Transcription
• 1.) DNA strand unzips
– The bonds between the nitrogen bases are
broken
• 2.) A single strand of mRNA (messenger
RNA) is made
– Pair up the bases
• 3.) mRNA travels from nucleus to
cytoplasm

49. Transcription

50. Why is mRNA called messenger
RNA?
• Because it carries the directions to make a
protein to the ribosome like a message

51. Translation
• mRNA meets up with a ribosome…why??
• tRNA molecules bring amino acids to
ribosomes
• An mRNA codon will pair with a tRNA
anticodon
– Codon: 3 Nitrogen base sequence in mRNA that
specifies a specific amino acid
– Anticodon: 3 Nitrogen base sequence in tRNA
• As tRNA’s are added, amino acids are bonded
together and will be released as a fully
functional protein.

52. Translation

53. That’s the process, Now how do you know what
amino acids make up a particular protein
• We use an mRNA codon chart