1. Come up with a team name that’s DNA-related (ish)
DNA CoMpEtiTiOn
Come up with a team name that’s DNA-related (ish)
Team with the most points gets a special prize! (Class with most overall points also gets a prize)

2. DNA

3. The information
stored on DNA
from one human cell
equals the amount of
information
in 1000, 500-page books.

4. DNA – Deoxyribonucleic Acid
A T
T A
C G
G C
G C
G C
DNA – Deoxyribonucleic Acid
DNA is made up of repeating…
Nucleotides – has 3 components:
Phosphate Group
Sugar – Deoxyribose
3. Nitrogen Base
Thymine always goes across from Adenine
Guanine always goes across from Cytosine
**The part that carries the code is the base sequence
Covalent bond – connects nucleotides in a strand
Hydrogen bonds – they connect the 2 strands together
Forms shape of DNA – DOUBLE HELIX

6. Erwin Chargaff Rosalind Franklin Watson & Crick
Chargaff’s Rule: [A]=[T] and [C]=[G]
X-Ray diffraction pictures helped solve the structure of DNA’s double helix
Rosalind Franklin
Watson & Crick
Finalized the structure of DNA and built the first ever DNA model

7. DNA is shaped like a double helix (a twisted ladder)
This shape was discovered by two scientists: James Watson & Francis Crick (Impossible without Rosalind Franklin’s X-Ray diffraction photo of DNA!)

9. DNA REPLICATION In general, DNA is replicated by
1. Uncoiling of the helix
2. Separating the strands (breaking the hydrogen bonds between base pairs)
3. Synthesizing two new strands by complementary base pairing

10. DNA REPLICATION Prokaryotes Eukaryotes
DNA replication begins at 1 point, called the “origin” and proceeds in 2 directions (bidirectional)
Hydrogen bonds break, two strands separate, 2 new strands are added to the old strands

11. DNA Replication –
DNA makes a copy of itself
Important during meiosis & mitosis – DNA gets passed on to daughter cells
DNA polymerase adds nucleotides to the parent strands and checks the strand for errors
Each double helix now has 1 old strand & 1 new strand
This is called SEMI-CONSERVATIVE
If the original strand of DNA is ATTGCACT, what is the complementary strand…?

12. The tips of chromosomes are called telomeres
Genes are not found in this region of the chromosome
These areas are difficult to replicate, so an enzyme – telomerase – adds short, repeated sequences to the ends

13. DNA Replication
Label ONE strand of your DNA with ANY sequence of your choosing
Label the opposite strand, following the base-pair rules (A – T, C – G)
What’s the 1st step in DNA replication
- The DNA “unzips” – crease your paper and “unzip” your DNA

14. DNA Replication 4. What’s the 2nd step in DNA replication?
- DNA Polymerase adds nucleotides
Lay your strands about 2” apart on a piece of paper
Next to each original strand, write the NEW complementary DNA sequence
You should now have 2 identical double-stranded molecules of DNA…yes?

15. DNA holds the directions for protein synthesis
Protein synthesis is the making of proteins
A gene is a sequence of DNA that carries the code for making one protein

16. Everything in you is made of or by proteins!
Protein Examples
Hemoglobin is a protein in your blood that transports oxygen
Collagen is a proteins that makes your cartilage and tendons
Keratin is a protein that makes up your hair & fingernails
Enzymes are proteins
Everything in you is made of or by proteins!

17. * It has uracil instead of thymine
Nitrogen Bases
Sugars
&
Phosphates
RNA
DNA
RNA – Ribonucleic Acid
RNA is like DNA except…
* It is single stranded
* It has uracil instead of thymine
* It has ribose instead of deoxyribose

18. Types of RNA mRNA – “messenger” RNA tRNA – “transfer” RNA
- Carries copies of instructions from DNA for making amino acids into proteins
tRNA – “transfer” RNA
- Transfers each amino acid to the ribosome as specified by the code on mRNA
rRNA – “ribosomal” RNA
- Makes up part of the ribosome, where proteins are made

19. 2 parts of protein synthesis:
Both DNA and RNA are involved in protein synthesis
2 parts of protein synthesis:
Transcription – DNA is converted to RNA
Occurs in the nucleus
Translation – RNA is converted to a protein
- Occurs in the cytoplasm

20. Protein Synthesis Transcription (the 1st part of Protein Synthesis)
Converts DNA to RNA
DNA (in the nucleus) needs to send a code to the ribosome (in the cytoplasm)
Problem: DNA can’t fit through the nuclear pores
A special “messenger” is used to copy and carry the code…
Ribosome

21. Protein Synthesis Transcription
messenger RNA (mRNA) goes into the nucleus and copies the DNA
Uses enzyme – RNA Polymerase
The next step is that mRNA moves from the nucleus to the cytoplasm and to the ribosome
RNA has 1 different base pair!
DNA – ATCG
mRNA – UAGC

22. Translation (the 2nd part of Protein Synthesis)
Translation – a process that converts mRNA into a protein
Occurs on the ribosome in the cytoplasm of a cell
______________ - building blocks of proteins; join together into long chains called polypeptides
____________ - a sequence of 3 bases on mRNA that codes for a single amino acid
_____________ – sequence of 3 bases on tRNA that is complementary to one mRNA codon
Amino acids
Codon
Anticodon
“UCU” is the codon that makes an amino acid called SERINE

23. p367

24. The tRNA lines up with 3 bases in mRNA (codon)
tRNA anticodon GAA
mRNA codon CUU
Another form of RNA called transfer RNA (tRNA) carries amino acids to the ribosome and matches them to the coded mRNA message
tRNA drops off the amino acid in the correct spot
mRNA attaches to the ribosome

27. Mutations
Any change in the DNA structure (specifically the order of nitrogen bases) is a mutation.
Mutations can be helpful, harmful, or neutral.
Helpful – can create diversity in a population
Harmful – can cause things like cancer
Neutral – can have absolutely no effect at all
A mutagen is something that causes mutations in the DNA (for example: smoking, radiation from the sun etc)
Slooze Worm

28. Mutations
An insertion mutation is when a nitrogen base is added to the existing DNA
A deletion mutation is when a nitrogen base is subtracted from the DNA
A substitution mutation is when one nitrogen base is put in place of another.
If our DNA was AATTGGCC
An insertion would be AATTAGGCC
A deletion would be AATGGCC
A substitution would be AAATGGCC

29. Gene Sequencing – Determining the order of nucleotide bases within a gene
DNA Fingerprinting – technique used in criminal investigations. DNA Fingerprinting takes the DNA out of a cell and separates it. This will allow investigators to distinguish body cells of different individuals (since they are unlikely to have the same DNA)
Cloning – take the DNA out of one of your cells then take the DNA out of a zygote (fertilized egg). Put the DNA from your cell into the zygote.

30. Genetic engineering is the process of moving genes from the chromosomes of one organism to those of another organism.
Recombinant DNA is formed by joining DNA molecules.from two different organisms
Animation

32. What would represent the strand of DNA from which the mRNA strand in the diagram was made?
A.CUCAAGUGCUUCB.GAGUUCACGAAG
C.GAGTTCACGAAGD.AGACCTGTAGGA
What is the amino acid sequence in the portion of the protein molecule coded for by the piece of mRNA shown in the diagram?
A. Ser-Tyr-Arg-GlyB.Leu-Lys-Cys-PheC.Val-Asp-Pro-HisD.Pro-Glu-Leu-Val