DNA JOBS REVIEW
• Replicate THIS!
ATCGGGGGTACTTT
TAGCCCCCATGAAA
ATCGGGGGTACTTT
TRANSCRIBE THIS
ATCGGGGGTACTTT
UAGCCCCCAUGAAA
Made of a
sugar,
phosphate,
and base
DNA
Gets transcribed
Deoxyribonucleic acid
Single stranded
RNA
Gets translated
ribonucleic acid
Double-stranded
C:G
A:T
A:U
DNA
RNA
Deoxyribonucleic acid
Gets transcribed
Double-stranded
A:T
ribonucleic acid
Made of a
sugar,
phosphate,
and base
C:G
Gets translated
Single stranded
A:U
Put these steps of transcription and translation in order…..
A. mRNA is processed and then leaves the nucleus.
B. The mRNA is translated into amino acid sequence.
C. Amino acids combine to form proteins
D. DNA is transcribed into mRNA.
E. The cell receives a signal to express a gene.
F. mRNA goes into the cytoplasm to the ribosome.
G. In the nucleus the double helix of DNA is opened up
Put these steps of transcription and translation in order…..
E. The cell receives a signal to express a gene.
G. In the nucleus the double helix of DNA is opened up
D. DNA is transcribed into mRNA.
A. mRNA is processed and then leaves the nucleus.
F. mRNA goes into the cytoplasm to the ribosome.
B. The mRNA is translated into amino acid sequence.
C. Amino acids combine to form proteins
Could you fill this blank flow chart in??
(Probable test question!!)
___
_____
TRANSCRIPTIO
TRANSLATION
protein
Replication
DNA
TRANSCRIPTION
TRANSLATION
mRNA
DNA
TRANSCRIPTION
mRNA
TRANSLATION
Occurs in nucleus
Occurs in
cytoplasm at
ribosome
Occurs in nucleus
protein
Review: Transcription and Translation
Write the Completed Paragraph
The process of transcription
and translation follows this path.
The cell receives a signal to express
a gene. In the ___, the double helix
of___ is opened up. DNA is ____
into mRNA. mRNA has the base
__instead of thymine. mRNA is
processed and then leaves the
nucleus. mRNA goes into the____ to
the ___. The mRNA is__ into a(n)
__sequence. These are the building
blocks of _____.
Word Bank
A. Cytoplasm
B. Transcribed
C. Nucleus
D. Translated
E. Ribosome
F. Uracil
G. Completed Proteins
H. DNA
I.
Amino Acid
Review: Transcription and Translation
Write the Completed Paragraph
The process of transcription
and translation follows this path.
The cell receives a signal to express
a gene. In the C, the double helix
of H is opened up. DNA is B into
mRNA. mRNA has the base F
instead of thymine. mRNA is
processed and then leaves the
nucleus. mRNA goes into the A to
the E. The mRNA is D into a(n) I
sequence. These are the building
blocks of G.
Word Bank
A. Cytoplasm
B. Transcribed
C. Nucleus
D. Translated
E. Ribosome
F. Uracil
G. Completed Protein
H. DNA
I.
Amino Acid
Gene Mutation Notes
A MUTATION is a change in the DNA
1) Chromosomal Mutations – affect MANY genes
ex. ie - Down syndrome
2) ***Gene mutations- affect a SINGLE gene –
smaller effect
I.
Frameshift Mutations
1.Insertion – a new base is ADDED to a codon
INSERT A “G” 
ex. AUG UAC GGU
AUG GUAC GGU
AUG GUA CGG U
2. Deletion – a base is REMOVED from a codon
REMOVE THE “U” 
ex. AUG
UAC GGU
AUG
AC GGU
AUG
ACG
GU
Huntington Disease: Caused by an
Insertion Mutation. You die young (40s or
50s) but you don’t normally know you
have it until after you have passed it on
to your children.
Neurodegenerative disease.
Cystic Fibrosis is a disease sometimes caused by a
deletion of a single T base. The hallmark symptoms of
cystic fibrosis are salty tasting accumulation of thick,
sticky mucous, frequent lung infections, coughing,
shortness of breath.
Inherited (Recessive Trait)
ii. Point Mutation (base substitution) one
base is EXCHANGED for another
1. Missense- a NEW amino acid is coded for
Ex. UUU is Phenylalanine
Ex. UUA is Leucine
Sickle cell anemia is caused by a single base
substitution!!! The “sickle” shaped red blood cells don’t
carry oxygen as well.
2. Silent – no CHANGE in the amino acid
sequence
Ex. CCC is Proline
Ex. CCG is Proline
Examples of disease caused by SILENT mutations….????
3. Nonsense- A STOP codon before gene is
done being translated (Stop codons are UAA,
UAG, UGA)
Ex. UGG is Tryptophan but UGA is STOP
!
Duchenne’s Muscular
dystrophy can be caused
by a nonsense mutation.
Look how much shorter
the protein is.
The disease causes
muscle weakness. It
usually leads to death
by the mid 30s
because muscles used
to breathe also get
weaker.
Types of Reproduction Notes
Notes: Types of Reproduction
***Key Idea: Genetic information is passed from
parents to offspring through CHROMOSOMES.
Remember that chromosomes are DNA and
PROTEIN. We have to get the chromosomes
from the parent cell to the new cells that are
being produced.
In ASEXUAL reproduction, ONE organism divides
in two and makes an EXACT COPY of itself.
This is essentially MITOSIS.
Ex. Budding in yeast
Ex. Amoebas
Pros : NO ENERGY used to get together with
another organism.
Cons  : Only ONE parent contributes genes.
Sexual Reproduction: Meiosis
In SEXUAL reproduction, TWO organisms must
come together to create an offspring that is
genetically DIFFERENT than either parent.
Pros  : Genes from BOTH parents contribute to
offspring.
Cons : Must USE ENERGY to get together with
another organism.
To reproduce sexually, the organisms must first
form “gametes.” Cells of the body have two
copies of sets of chromosomes. Gametes only
have one set. Why?
DIPLOID cells have two sets of chromosomes. We
represent this as 2n.
HAPLOID cells have one set of chromosomes. We
represent this as n.
Haploid
Diploid
In humans, the MALE gamete is the SPERM.
The FEMALE gamete is the EGG.
The sperm swims up the female reproductive tract and
FERTILIZES the egg.
The egg and sperm together is called a ZYGOTE
The ZYGOTE then divides by MITOSIS to form a
multicellular (many-celled) organism. Mitosis is just
plan old cell division.
The process of forming a gamete is
called MEIOSIS.
Steps of Meiosis
1)
2)
3)
4)
Replication
Pairing up of homologous chromosomes.
First division
Second division
Mitosis
Cell divides
once. You get
two cells
identical to
the original.
Each have
two copies of
each
chromosome
Two cell divisions. You get four
cells that are genetically
different than the original cell.
Each have one copy of each
chromosome.
Meiosis
2) Pairing up of homologous chromosomes.
o HOMOLOGOUS CHROMOSOMES are both sets of
chromosomes.
o Ex. Both copies of chromosome 12
o ***Genetic material is exchanged or shuffled between
the homologous chromosomes in a process called
CROSSING OVER. This produces the NEW
combinations of traits that were not seen in either
parent.
Homologous Chromosomes
Homologous Chromosomes
Crossing Over!
3) First division- Result is two haploid cells with
replicated chromosomes.
4) Second division- Result is 4 haploid cells with
unreplicated chromosomes. (Result is the egg
or sperm).
Mitosis
(asexual)
Meiosis
(sexual)
1
2
2
sets of chromosomes
in cells produced
2n
n
type of cells it occurs
in
all cells
# of divisions
# of cells produced
homologous
chromosomes pair
up?
genetic variety of
offspring increased
NO
NO
4
reproductive tissues
only
yes
YES
Mitosis
Here are the two
chromosome #5s in a 2n
(diploid cell).
Replication occurs. Each
chromosome is copied to
prepare for division.
The cell division occurs. The
replicated chromosomes are
separated.
Homologous chromosomes
DO NOT pair. All
chromosomes line up in the
middle of the cell “single
file.”
The product is 2
cells that are
diploid (2n). This is
exactly what we
started with.
Meiosis
Replication occurs. Each
chromosome is copied to
prepare for division.
Here is one set of chromosomes.
For example, the two sets of
chromosome #5. We call the two
sets “homologous chromosomes.”
This is a diploid (2n) cell.
The first division and
crossing over occurs.
Homologous chromosomes
separate.
The second division occurs
and the replicated
chromosomes separate.
We now have haploid (n)
cells with replicated
chromosomes.
We now have 4
haploid (n) cells with
unreplicated
chromosomes.
Mitosis
2n diploid
cell
REPLICATION
Chromosomes line
up single file in
middle of cell.
DIVISION
Meiosis
2n diploid
cell
REPLICATION
Homologous
chromosomes pair and
line up “two by two.”
Crossing over occurs to
increase genetic variety.
FIRST DIVISION
Haploid (n) cells
with replicated
chromosomes.
SECOND DIVISION
4 haploid (n)
cells with
unreplicated
chromososo