Download DNA PowerPoint 2017

DNA - Chapter 12
DO NOW
● True or False?
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The first cloned animal was a tadpole.
You inherit more from your father if you are a boy.
Identical twins do NOT have the same DNA.
All humans share 75% of their DNA.
DNA is in all our cells except for red blood cells
Each cell contains 2 meters of DNA
DNA is coiled up into 46 chromosomes
If you look more like one of your parents, you
inherited more DNA from them
○ We share 50% of DNA with a banana
DO NOW
● True or False?
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The first cloned animal was a tadpole. F
You inherit more from your father if you are a boy. F
Identical twins do NOT have the same DNA. F
All humans share 75% of their DNA. F
DNA is in all our cells except for red blood cells. T
Each cell contains 2 meters of DNA. T
DNA is coiled up into 46 chromosomes. T
If you look more like one of your parents, you
inherited more DNA from them. F
○ We share 50% of DNA with a banana. T
Objectives
1. SWBAT extract DNA from
a strawberry.
2. SWBAT dissolve the
phospholipid bilayer and
break up protein chains
that bind around the
nucleic acid.
Objectives
● SWBAT identify the parts of a nucleotide
● SWBAT label the different parts of a DNA
molecule.
● SWBAT create their own DNA molecule.
DO NOW
● DNA stands for:
● DNA is located:
● The function of DNA is to:
DO NOW
● DNA stands for:
○ Deoxyribonucleic acid
● DNA is located:
○ In the nucleus of cells
● The function of DNA is to:
○ Tells the cells how to produce proteins that
make you up (Blueprint)
DNA Structure
A Nucleotide is made of a:
○ 5 carbon sugar (Deoxyribose)
○ Phosphate Group
○ Nitrogen base (adenine, cytosine, guanine, thymine)
Nitrogen Bases
Nitrogen Bases cont...
What pairs up?
Adenine - Thymine
Cytosine - Guanine
How many bonds does each have?
DNA Structure
DNA Structure
● DNA often is compared to a twisted ladder.
● Rails of the ladder are represented by the alternating
deoxyribose and phosphate.
● The pairs of bases
(cytosine–guanine or
thymine–adenine) form
the steps! Nitrogen bases
point in
Base PairsRungs of the
ladder
2 Strands of DNA
form a helix
Orientation of DNA - Antiparallel
▪ On the top rail, the strand is said to be
oriented 5′ to 3′.
▪ The strand on the bottom runs in the
opposite direction and is oriented 3′ to 5′.
DO NOW: Hint- #1 and 6 refer to the ends of DNA
Objectives
1. SWBAT identify the parts of a nucleotide
2. SWBAT create their own strand of DNA
using template sugar, phosphate, and bases.
Label the parts of the DNA molecule
Extra Resources → Click the links
History of DNA
DNA Structure
DO NOW
● Where is DNA located?
● What is the role of DNA in the cell?
Objectives
1. SWBAT explain what Chargaff, Franklin,
and Watson/Crick discovered.
2. SWBAT create a timeline of the scientists
that discovered DNA.
3. SWBAT label parts of the DNA molecule
4. SWBAT describe how a chromosome coils.
Discoveries that led to understanding
the structure of DNA!
Levene - Chargaff - Franklin - Watson & Crick
Levene
Discovered that DNA is made of nucleotides
Erwin Chargaff
Chargaff’s rule:
C = G and T = A
Discovered what
base pairs bonded
together!
Rosalind Franklin
● X-ray Diffraction use of
photo 51
● X-ray diffraction data helped
solve the structure of DNA
● Indicated that DNA was a
double helix
X-Ray Crystallography
Watson and Crick
Built a model of the double
helix that conformed to the
others’ research →
What their model confirmed was:
● Two outside strands consist of alternating sugar and
phosphate molecules
● Cytosine and guanine bases pair with 3 H bonds
● thymine and adenine bases pair with 2 H bonds
Ground Breaking Discoveries in
Bacterial Transformation
Griffith - Avery
Bacterial Transformation - process by
which bacterial cells take up naked DNA molecules
Why do we care about bacterial transformation?
● Genetic
Research
● Antibiotic
Resistance
Fred Griffith
● Studied two strains of bacteria,
Streptococcus pneumoniae
● Worked with two strains of bacteria:
Rough Strain and Smooth Strain
● S strain causes pneumonia and the R
strain does not
Griffith
● S strain:
● Heat killed S strain:
● R Strain:
● Heat killed S strain + R Strain:
Fred Griffith - 1928
● Discovered that something from
the heat killed wild type
(smooth) bacteria was turning
the mutant (rough) type bacteria
into smooth.
● Called it the transforming factor
● Didn’t really know what it was
Avery
● Identified the molecule that
transformed the R strain of
bacteria into the S strain
● Concluded that when the S cells
were killed, DNA was released
● R bacteria incorporated this
DNA into their cells and changed
into S cells.
● Many people did not believe that
it was DNA, not protein that
transformed genes
Objectives
● SWBAT list and identity the characteristics
of viruses
● SWBAT label a diagram of the life cycle of
a virus
● SWBAT explain Hershey and Chase’s
experiment and it’s importance to the
discovery of DNA
VIRUSES!
DO NOW
List as many types of viruses you can think of!
Viruses - Six Characteristics
1. Have their own genome (genetic make up)
made of either DNA or RNA
2. Does not have enzymes, ribosomes, or ATP
3. Have external protein shells (capsids)
Viruses - Six Characteristics
4. Infect only specific cells
5. 2 life cycles (lytic and lysogenic)
○ Lytic – breaks out and spreads
○ Lysogenic- hangs around
6. Smaller than bacteria
When a virus attacks a cell
Put the following pictures in order!
Lytic vs. Lysogenic Cycles
THINK - PAIR - SHARE
Compare how the lytic and lysogenic cycles are
different from each other and how they are similar
Lytic
Lysogenic
Both
DO NOW - What is this virus doing?
Discoveries Involving DNA and Viruses
Hershey & Chase
Hershey
& Chase
● Used radioactive labeling to trace the DNA
and protein
● Concluded that the viral DNA was injected
into the cell and provided the genetic
information needed to produce new viruses
Hershey and Chase
Radioactive Labeling:
○ Used radioactive phosphorus (32P) to identify
DNA in the bacteriophages
○ Used radioactive sulfur (35S) to identify proteins
in the bacteriophages
Hershey and Chase
● Tracking DNA
● Radioactive bacteriophages infected
bacteria cells
● After review results found radioactive sulfur
outside of bacteria cells and radioactive
phosphorus inside bacteria cells
DO NOW
1. What is a virus?
2. Why is a virus NOT considered a living thing?
3. What are the two types of life cycles of
viruses? Briefly describe each.
DO NOW
1. Briefly describe Griffith’s experiment
2. What did he conclude?
DO NOW
1. Briefly describe hershey and chase’s
experiment.
2. What did they conclude?
DO NOW
1. Find the complementary sequence of DNA:
ATCGGATATAGC
2. What bonds form between the sides of DNA?
3. What type of sugar is in DNA?
4. What does 3’ mean?
Objectives
1. SWBAT explain what Chargaff, Franklin,
and Watson/Crick discovered.
2. SWBAT create a timeline of the scientists
that discovered DNA.
3. SWBAT label parts of the DNA molecule
4. SWBAT describe how a chromosome coils.
THINK-PAIR-SHARE
Create a timeline of all the
scientists and what they
discovered.
Do Now - How do you think your DNA gets
in every cell of your body? Explain.
DNA Replication
Objectives
● SWBAT explain the different forms DNA can
be found in (chromatin, chromosomes, etc.)
● SWBAT define semiconservative replication,
helicase, ligase, DNA polymerase, and
replication.
● SWBAT explain how DNA Replicates
● SWBAT extract DNA out of a strawberry.
Chromosome Structure
● DNA coils around histones (proteins) to
form nucleosomes.
● This coils to form chromatin fibers.
● The chromatin fibers supercoil to form
chromosomes that are visible in the
metaphase stage of mitosis.
This is known to
be condensed
Semiconservative Replication
▪ Parental strands of DNA separate
▪ Each strand serve as template
▪ DNA molecules produced have one strand
of parental DNA and one daughter strand
Enzymes involved in DNA Replication
Steps to DNA Replication
1. Unwinding
● DNA helicase (enzyme) unwinds and
unzips the DNA – breaking the hydrogen
bonds between the strands
● RNA primase adds a short segment of
RNA, called an RNA primer, on each DNA
strand.
Steps to DNA Replication
2. Base Pairing
● DNA polymerase (enzyme) adds
complementary nucleotides to parent DNA
strand
● Only adds to 3’ end of new DNA strand
2. Base Pairing (cont.)
Two daughter strands of DNA are made differently
Leading Strand- Built continuously without breaks
Lagging Strand- makes several small fragments of DNA
● Built discontinuously
● Pieces are called Okazaki Fragments
● Fragments are connected by DNA Ligase
Steps to DNA Replication
3. Joining
● DNA Polymerase removes RNA Primer
and fills it in place with DNA nucleotides
● DNA ligase links two sections
Animations of DNA Replication
● Animation 1
● Animation 2
● Animation 3
Do Now
● Label the DNA Replication Diagram
Do Now
● What is DNA replication?
● Why is it called semiconservative?
● What is DNA helicase?
Do Now
Label the DNA strands.
Add in: new strands
Enzymes
5’/3’ ends
Let’s Practice
5’
DNA Replication in Eukaryotes and Prokaryotes
● Eukaryotic DNA unwinds in multiple areas as
DNA is replicated.
● In prokaryotes, the circular DNA strand is
opened at one origin of replication.