Download DNA - Madison County Schools

DNA
Mrs. Foles
2010-2011
Jag Mark 9/1/10
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How long did you study for your test that you
took yesterday?
How do you feel about your performance on
the test you took yesterday?
How will you change the way/length of time
that you study for the next test?
Jag Mark 9/2/10
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What do plants give off as a waste product
during photosynthesis?
What do we give off as a waste product
during cellular respiration?
Jag Mark 9/3/10
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Summarize the difference between
autotrophs and heterotrophs.
Jag Mark 9/7/10
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What 3 things are in a plant cell that are
missing in an animal cell?
What biological process produces new cells
to replace older cells?
What is the correct organization of life
beginning with cells?
Jag Mark 9/8/10
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What is the structure of DNA?
Draw and label a nucleotide.
Practice
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Template Strand:
ATCGGTACGTACGTAG
Complement Strand:
Jag Mark 9/9/10
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Describe the 4 different types of organic
compounds involved in metabolic activities.
What makes these compounds organic?
Replicate the following DNA strand.
–
AGTCGTAGCTCGATGCTTA
Jag Mark 9/10/10
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Complete the steps of protein synthesis with
the following strand of DNA. (Explain the
location and process of each step)
TACGACGTAACT
Jag Mark 9/13/10
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What materials make up a nucleotide?
Draw and label a strand of DNA.
Jag Mark 9/14/10
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Summarize the differences between DNA
and RNA.
Jag Mark 9/15/10
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Explain why virus are nonliving.
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What are the main components of all
viruses?
Jag Mark 9/16/10
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What type of mutation would result in the
following mutant strand of DNA?
– Normal:
ACTCCTGAAGAAAAA
– Mutant:
ACTCCTGTAGAAAAA
Would this mutation cause a change in the
protein being synthesized?
Is this a point-shift or frame-shift mutation?
Jag Mark 9/17/10
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Outline 3 ways to protect yourself from
viruses.
Jag Mark 9/20/10
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Summarize the differences between the lytic
cycle and the lysogenic cycle.
Jag Mark 9/21/10
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TEST DAY!
Clear desk except for 1 sheet of notebook
paper and a pencil.
Organic Compounds: (Contain Carbon)
Of Metabolism!

Carbohydrate: a
compound
composed of
carbon, hydrogen,
and oxygen in the
proportion of 1:2:1.

Lipids: compound that
contains a high
proportion of carbon
and hydrogen with a
much smaller amount
of oxygen. (Fats, oils,
and waxes.
Organic Compounds: (Contain Carbon)
Of Metabolism!

Proteins: a large
molecule made from
amino acids.
(enzymes: proteins
that speed up
reactions)

Nucleic Acid: large
molecule that stores
and carries genetic
information in the cell.
(DNA,RNA)
What is DNA?
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Deoxyribonucleic
acid
Codes for genes
and is used in the
development and
functioning of all
living things.
Credit for structure
is given to Watson
and Crick.
What is it made of?
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DNA is made up of 4 types of Nucleotides
All nucleotides are identical except for the base
Each nucleotide has 3 materials:
–
–
–
A sugar: deoxyribose
A phosphate
A base
The bases of DNA

Pyrimadine: 1 ring
–
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Thymine (T)
Cytosine (C)
Purine: 2 rings
–
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Adenine (A)
Guanine (G)
Structure and Base Pairing of DNA
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Base Pairing
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Adenine pairs with Thymine (A=T)
Cytosine pairs with Guanine (C≡G)
Structure
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Twisted Ladder/Double Helix
Sides of Ladder
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–
Alternating Phosphate and Sugar
Rungs of Ladder
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Pair of nucleotide bases
DNA Replication
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DNA molecule sides are
complementary to each
other, therefore DNA can
replicate itself if nucleotides
are present.
When DNA replicates, the
bases break apart and the
DNA unwinds and unzips.
Semi-conservative
Where does replication take place?
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In the nucleus! During what phase of the cell
cycle?
Practice:
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Template:
Replicate:
ATTGCAGGCCTTAGTCAC
Practice Problem
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AGTTCAGCGGTATTAGCTAGCAACCGT
RNA
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DNA can’t leave the nucleus, so it must be
“transcribed” into something that can: RNA
Three Types:
–
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mRNA: (messenger) Takes code from DNA in
nucleus to ribosome
tRNA: (transfer) Brings in amino acids to build
proteins
rRNA: (ribosomal) Makes up ribosomes
RNA

RNA is similar to DNA
because
–
–
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It is composed of
nucleotides
BASES: It has C, G, and
A.
It has a backbone
composed on
phosphates and sugars

RNA is different than
DNA because
–
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BASE: Instead of
Thymine bases there are
Uracil bases
SUGAR: Instead of
dexoyribose there is
ribose.
RNA is single stranded
Transcription
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An enzyme in the
nucleus begins
transcription to form
mRNA from DNA.
mRNA leaves the
nucleus and binds
to a ribosome.
Transcription
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DNA strand: ATACTGTCAGTATGGCCAT
RNA strand:
Practice problem:
TATTACGACCCGTACTAGAATGGCTCC
Reverse Transcription
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DNA strand:
RNA strand: UAGGCUACUGAUCCAAUG
Translation
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After mRNA leaves the nucleus it binds to a
ribosome in the cytoplasm.
mRNA is read as codons: (three base pairs
in a row.)
tRNA brings amino acids to the mRNA that is
specific for the codon and forms a peptide
chain.
Transcription and Translation
Translation Practice
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mRNA:
Amino acid:
Practice
mRNA:
tRNA:
Amino acid:
AUG AGC UGG GGG UAU UAG
Met Ser Leu Gly Tyr Stop
AUG UGU AGC CCU AUU UAA
Central Dogma of Protein Synthesis
Translation
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There are 4 base pairs
20 amino acids
AUG = Start codon
UAA, UAG, UGA = Stop codon
When making proteins, extra amino acids
must be brought from cytoplasm.
Proteins
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Made of amino
acids (the building
blocks of proteins)
Several amino acids
make a peptide
chain
Amino acids held
together by peptide
bonds
What is a gene?
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Instructions for building proteins, traits, and is
located on DNA.
Genes are found on chromosomes.
Must have a start codon
Must have a stop codon
Must have a promoter region (TATATTA)
Mutation
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Mutations are changes to the base pair
sequence of either DNA or RNA.
Causes: copying errors in the DNA during
mitosis and by exposure to ultraviolet radiation,
xrays, radioactivity, or viruses.
Results: genetic disorders, death, or have no
affect.
Most mutations are repaired by enzymes.
Types of Mutation
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Insertion: the addition of one or more
nucleotide base pairs into a genetic sequence
–
Ex: Normal: AAACCCGGG
Mutated: AAACACCGGG
Types of Mutation
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Deletion: part of a
chromosome or a
sequence of DNA is
missing. Any number of
nucleotides can be
deleted, from a single
base to an entire piece
of chromosome.
Example
Normal: AAACCCGGG
Mutated: AAACCGGG

Types of Mutation
Substitution: one or
more nucleotides are
substituted by the same
number of different
nucleotides. In most
cases, only one
nucleotide is changed.
 Example:
Normal: AAACCCGGG
Mutated: AAACACGGG
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Types of Mutations
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Frame-shift mutation: causes a change all the
way down a DNA sequence, making each codon
a different sequence. (MORE SERIOUS!)
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EX. CAG TTC CTG GAA -> (frameshift)-> CAG TTA CCT GGA
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Insertion
Deletion
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Point-shift mutation: a single letter is the only
thing changed in the DNA sequence
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EX. GTA CTG CAA-----> (point mutation) -----> GTA GTG CAA
–
Substitution
Cell Growth and Repair
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Cell Cycle the entire life cycle of a cell.
Cells divide through a process called Mitosis.
Phases of Mitosis
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Prophase: The chromatin condenses into
chromosomes. Each chromosome has
duplicated and now consists of two sister
chromatids. The nuclear envelope breaks down
into vesicles.
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Chromatid: name of chromosome once it is
duplicated
Centromere: Holds chromatid together
Metaphase: Chromosomes line up at the
equator of the cell.
Phases of Mitosis
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Anaphase: Sister chromatids separate and
move toward the opposite poles.
Telephase: The condensed chromatin
expands and the nuclear envelope
reappears. The cytoplasm divides.
Cytokinesis: The cell membrane pinches
inward ultimately producing two daughter
cells.
During Cytokinesis
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In plant cells a cell plate forms in between
the new cells and will become the cell
membrane. A cell wall then forms around
the cells.
Cancer
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Cancer is a disease in which cells grow and
divide uncontrollably, damaging parts of the
body around them.
Virus
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Virus is a tiny non-living particle that enters
and then reproduces inside a living host cell.
Have either DNA or RNA.
May be single stranded or double stranded.
Nonliving because cannot: make food, take
in food, use energy, respond to stimuli, make
waste or multiply on their own.
Bacteriophage is a virus that infects bacteria.
Virus Shape and Size
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Viruses are smaller than bacteria (measured
in nanometers)
Structure: (2 main Parts)
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Protein Coat
Inner Genetic Material (DNA or RNA)
How Viruses Multiply
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Lytic Cycle: Virus enters cell and uses cell to
reproduce. (Ex. Flu, Rhinovirus)
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Viral DNA destroys Cell DNA, takes over cell
functions and destroys the cell.
The Virus replicates.
There are symptoms of viral infection.
Active viral infection takes place.
How Viruses Multiply
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Lysogenic Cycle: Virus enters cell and becomes
part of cells DNA. May enter lytic cycle is
exposed to stress. (Herpes, cold sores.)
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Viral DNA merges with Cell DNA and does not destroy
the cell.
There are no symptoms of viral infection.
Passive viral replication takes place.
Lysogenic/Lytic Cycle
Lytic VS Lysogenic Cycle
Ways to Protect
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Vaccinations: weakened or dead viruses
injected into the body to stimulate immune
response. (Antibodies form against virus)
Proper hygiene/hand washing
Minimize risk by avoiding risky behavior.
(ex. IV drug use, unprotected sex)
Cancer
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Some viruses have been linked to the
formation of tumors.
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HPV linked to cervical cancer
Hepatitis B and C linked to liver cancer
Epstein-Barr linked to lymphoma