BIOLOGY CH13 POWERPOINT OUTLINE PART 1
NAME___________________________
PLEASE FILL IN THE BLANKS AND ANSWER THE NUMBERED QUESTIONS
CHAPTER 13: DNA, RNA, and Proteins
Essential Questions:
What is DNA?
How is DNA related to traits?
What is the Central Dogma of Biology?
Who discovered DNA?
DNA- The Genetic Material
Why should I care about DNA?
DNA stores the information that tells cells which __________________________ to make
Your proteins give you your physical & ___________________________ identity
Your DNA is different from everyone else’s DNA on earth
1. HOW COULD YOUR DNA BE USED TO IDENTIFY YOU??
Does DNA have anything to do with why I am so special?
Yes, it’s the variability of DNA that makes us all different!
2. HOW SIMILAR (%) IS YOUR DNA FROM THE PERSON SITTING NEXT TO YOU?
A CHIMPANZEE?
A FLY?
The Central Dogma of Biology
DNA is transcribed into RNA->RNA is translated into Proteins
Proteins give you your traits or Phenotype
3. GIVE AN EXAMPLE OF A PROTEIN THAT GIVES YOU AN IDENTIFIABLE TRAIT
Searching for the Genetic Material
Griffith - Discovered the transformation of harmless R strain Bacteria by heat killed S bacteria
Avery – Identified DNA as the transformative agent
Hershey & Chase –Studied bacteriophages and proved ______ was the source of hereditary information
4. HOW DO VIRUSES INFECT CELLS?
Who Discovered the Structure of DNA?
James Watson & Francis Crick discovered the structure of DNA after observing an X-ray picture of it taken by
Rosalind Franklin
5. WHICH SCIENTISTS EARNED THE NOBEL PRIZE FOR THIS DISCOVERY?
The Structure of DNA
DNA is an Alpha Double Helix
Composed of two strands of ________________________
Joined like a twisted ladder by hydrogen bonds
6. DRAW A SIMPLE DIAGRAM OF DNA
The Structure of DNA
The Structure of DNA is both complex and simply elegant
DNA is a polymer of Nucleotides- remember a _____________________________ is like a chain of beadsDNA is made of 2 chains
There are 4 different Nucleotides (beads) abbreviated as A, T G, or C
The Base on one chain “complements” and makes a bond with the base on the opposite chain
The bases are bound together by hydrogen bonds.
The two strands are twisted together
DNA Structure
DNA is a polymer of nucleotides (the _______________ on the chain)
Each Nucleotide contains 1 Nitrogenous base + 1 phosphate group + 1 sugar
In DNA the sugar is deoxyribose
7. DRAW A SIMPLE DIAGRAM OF A NUCLEOTIDE
The Structure of DNA
There are 4 different Nucleotides identified by their Nitrogenous Bases:
Adenine Guanine
(the purines)
Cytosine Thymine (the pyrimidines)
The Bases are said to “_______________________________” one another - A bonds to T, G bonds to C according to the
base pairing rules (also called Chargraffs Rules)
The bases are bound to each other by hydrogen bonds.
8. IF 1 STRAND OF DNA HAS THE SEQUENCE
AAATATCATCCT
WHAT IS THE COMPLIMENT STRAND
SEQUENCE?
The Structure of DNA
The DNA Double Helix is composed of 2 interconnected nucleotide chains
The nucleotide chains are composed of a Sugar-Phosphate __________________, with bases in the middle
The Nucleotides are joined by Phospho-diester bonds
The two strands are twisted together and joined by _______________________ bonds between the bases
DNA Replication
Why does DNA replicate?
Cells get worn out, new cells must be made (REMEMBER ______________________)
New cells must make exact copies of themselves
Copies of replicated genes can be passed on to offspring (______________________ TOO!)
9. How long is DNA in base pairs (bp)??
How is DNA Replicated?
10. Diagram DNA REPLICATION here
1. Helicase breaks hydrogen bonds in the middle of the
strand, creating a replication __________________
2. Unpaired bases form new bonds with free nucleotides in
the cell
3. New strand is rewound together by _____________
Polymerase, creating 2 identical DNA molecules
FUN FACTS

Sometimes replication errors occur
(A bonds to a ________)

There are 3 x 109 bp in the average cell

Takes about 4 hours for a cell to replicate its DNAMultiple __________ start simultaneously

The process is SEMI-Conservative, I.E. each new
DNA molecule has one ___________ strand
11. How many Genes are on your DNA approximately?
Transcription
DNA is located in the _______________________ of the cell
DNA CANNOT leave the nucleus of the cell because it is ________________________________________.
Mr. Dougherty! I am afraid for the DNA, it can’t get to the ribosome to be translated! What will it do?
Relax, RNA is the key!
Imagine the nucleus is like a library,
where each book is a gene.
…but you can’t take any books out!
You could make copies of the books…
That’s how RNA works….
Check out this cool video to help you understand.. http://www.pbs.org/wgbh/nova/body/rnai.html
What is RNA?
A nucleic acid that is similar to DNA
Ribose is the sugar in stead of _______________________________
The nitrogenous base Uracil is found in place of Thymine
Single stranded
12. How is Uracil diferent from Thymine?
Steps of Transcription
1. DNA strand unwinds via RNAPolymerase (not helicase)
2. Free nucleotides bond to bases, except U in RNA bonds to A from DNA
3. RNA polymerase joins single stranded RNA together
4. Messenger RNA (mRNA) moves to the _______________________ in the cytoplasm (or on the Rough ER)
13. If the DNA strand is TAC CAT GAT CTT GTT what is the mRNA sequence?
Translation (Protein Synthesis) ESSENTIAL QUESTIONS
What is protein synthesis?
The Conversion of RNA to Amino _________________ which make up proteins
Why is it called translation?
The genetic code (ATCG) is translated into a protein
Where does it occur? At the _______________________________ in the cytoplasm
Why is it called translation? The genetic code (ATCG) is translated into a protein
14. How old are my Genes?
Translation and the Genetic Code
RNA is composed of 3 letter “words” called CODONS
Each codon of RNA represents a specific Amino Acid
For instance AUG is the start codon, and UUU represents the amino acid Phe (__________________________)
Translation and the Genetic Code
Genetic Code Problem
15. If the DNA code is
AAT GCG TTT CGC ATA TAT
Then the RNA compliment is
___ ___ ___ ___ ___ ___
and the Amino Acid sequence that results is
____ ____ ____ ____ ____ ____
How Does Translation Occur?
The 3 Steps of Translation
1. Initiation
A. Ribosome attaches to mRNA (each 3 bases is called a codon)
B. tRNA brings anticodon and AA to ribosome
2. Elongation
A. More tRNA’s bring more AA’s to ribosome
B. AA’s connected together to make polypeptides (by peptide bonds)
3. Termination
A. Ribosome reaches a STOP signal on mRNA
B. Polypeptide (protein) is broken off and becomes part of the human body
C. Golgi apparatus modifies completed protein; ER transports it in/out of cell
The processes of transcription and translation are the same in all living organisms!