DNA & RNA
Unit 7
Chapter 12
DNA
Deoxyribonucleic Acid
RNA
Ribonucleic Acid
Where does DNA “live”?
The NUCLEUS!
Why is DNA so Important?
* DNA is a nucleic acid that contains the genetic
information used in the development and
functioning of all living things and some viruses.
* DNA is like blueprints, instructions, or a code for
making proteins
* DNA’s codes are converted/changed into
messages (mRNA) for ribosomes to read
and then make proteins.
* Proteins do most of the hard work of
keeping us alive
What are the parts of DNA?
*
The
“Backbone”
Has 2 Parts
D = Deoxyribose
(SUGAR)
P = Phosphate
2 Strands called:
Double Helix
What are the parts of DNA?
*
The
“Rungs”
The Nitrogen Bases
A = Adenine
A
T
T = Thymine
C = Cytosine
C-G
G = Guanine
How to remember
Nitrogen Bonds:
A bonds with T
Think: A T & T
phone company
How to remember
Nitrogen Bonds:
C bonds with G
Think: Half circles
Clicker Question #1
These are 2 examples of
nucleic acids:
A.
B.
C.
D.
Chloroplasts & Mitochondria
Carbohydrates & Lipids
DNA & RNA
Nucleus & Ribosomes
Clicker Question #2
DNA holds the
instructions for making:
A.
B.
C.
D.
Energy
Proteins
Carbon dioxide
Deoxyribose
Clicker Question #3
If 20% of a DNA’s strand
contains Thymine, then:
A.
B.
C.
D.
it also has 80% Guanine
it also has 50% Cytosine
it also has 80% Adenine
it also has 20% Adenine
Clicker Question #4
What type of sugar is
found in DNA?
A.
B.
C.
D.
Phosphorous
Thymine
Ribose
Deoxyribose
Clicker Question #5
The DNA’s code is converted into
_____ so it can be sent to
ribosomes to make the proteins.
A.
B.
C.
D.
DNA
mRNA
tRNA
ATP
What are the parts of DNA?
*
Nucleotides:
1 Sugar
1 Phosphate
1 Nitrogen Base
Lets Practice:
What are the complementary nitrogen
bases in this sequence of DNA?
ATT CGT TAT CGT CTG AAA ACG
TAA GCA ATA GCA GAC TTT
Yes!
We made
DNA!
What did we
just do?
TGC
Why is mRNA Important?
*
DNA is too big and CAN’T leave the
nucleus…it must send messages
* mRNA is created by DNA in the nucleus
* mRNA contains the messages from
the DNA and are sent to ribosomes
for them to read the instructions for
making proteins
What are the parts of RNA?
*
Just
RNA
Like
is DNA,
MadeRNA
of: has:
Ribose Sugar
(SUGAR)
BUT…..
Phosphate
Phosphate
(same as DNA)
NitrogenNitrogen
Bases (A,U,
BaseC, G)
First:
THYMINE
in RNA!!
UNO
stands
for Uracil….
Notice that
RNA
has
1
Strand!
a different nitrogen base
RNA Nitrogen Bases:
A bonds with U
THYMINE in RNA!!
C bonds with G
Clicker Question #6
What 3 things make up a
nucleotide?
A.
B.
C.
D.
Nucleus, DNA, & RNA
Adenine, Thymine, & Cytosine
Sugar, Phosphate, & a Nitrogen base
Chromosomes, Genes, & DNA
Clicker Question #7
Where is mRNA made?
A.
B.
C.
D.
In the nucleus
In the cytoplasm
In the mitochondria
In the ribosomes
Clicker Question #8
What type of sugar does
RNA have?
A.
B.
C.
D.
Deoxyribose
Carbohydrate
Ribonucleic acid
Ribose
Clicker Question #9
Which of the following
nitrogen bases does RNA
not have?
A.
B.
C.
D.
Uracil
Thymine
Adenine
Cytosine
Clicker Question #10
If a strand of DNA
contains 40% of Cytosine,
then
A.
B.
C.
D.
it also contains 40% Guanine
it also contains 60% Thymine
it also contains 40% Cytosine
it also contains 60% Guanine
How does DNA tell the cell to make
a specific kind of protein?
*
There are 2 major steps in this process
* First: Transcription
* Second: Translation
How does DNA tell the cell to make
a specific kind of protein?
Transcription :
Process in which mRNA is
synthesized from the DNA template.
HINT:
*** Transcription is when mRNA is made from DNA.***
*
mRNA: (messenger RNA) holds the
recipe for making proteins
How does Transcription work?
* QUESTION…have you been to court?
* There is a person typing what is said and is creating a
“court transcript”…which is really a code…shortened
version…and later the transcript is translated into all
the words that were said for a record.
SHORTENED CODE = mRNA
Transcription Video….
Lets Practice:
Create a RNA strand using this
sequence of DNA?
ATT CGT TAT CGT CTG AAA ACG
UAA GCA AUA GCA GAC UUU UGC
This is
mRNA!
We just
transcribed
DNA into
mRNA!
Clicker Question #11
What does mRNA do?
A. It carries the instructions from DNA to
ribosomes to make proteins
B. It carries instructions from the ribosomes
to the nucleus to make DNA
C. It carries the instructions from the
nucleus to the mitochondria to make
energy
D. It carries instructions from the nucleus to
the cytoplasm to make energy
Clicker Question #12
What is transcription?
A.
B.
C.
D.
The process of making energy
The process of making proteins
The process of making DNA
The process of making mRNA
Lets Practice This Again:
Create a RNA strand using this
sequence of DNA?
ACA CGA TTA CGG ATA CGC ATC
UGU GCU AAU GCC UAU GCG UAG
Now did
What
wewhat?
just do?
YES!
We transcribed/made
mRNA from DNA
Now What?...Translation!
Translation: Process in which mRNA attaches
to the ribosome and a protein is
assembled/made.
Words to know:
* Codon: 3 base code in DNA or RNA
* Amino Acid: Compounds joined by peptide bonds
ACG ATA
CGG CTT
to build proteins
There are 20 different Amino Acids.
* Different
Ribosomecombination
: “Reads” mRNA
it can make
ofrecipes
AminosoAcids
different
kinds ofproteins
proteins.
synthesize/make
Now What?...Translation!
More Words to know:
*
tRNA: (transfer RNA) Type of RNA that
transports amino acids to the ribosome
tRNA
Amino
Acid
* Anticodon: Nitrogen bases that canAnticodon
pair that
corresponds with the codons on the mRNA
What happens during
translation?
Peptide chain/
Protein Chain
tRNA
Amino
Acid
Anticodon
Ribosome
Codon
Translation Video...
Link to Transcription Animation
Click Here
Clicker Question #13
Where does translation
occur?
A.
B.
C.
D.
In the nucleus
In the mitochondria
In the DNA
In the ribosome
Clicker Question #14
What is made during
translation?
A.
B.
C.
D.
DNA
mRNA
Protein
Energy
Clicker Question #15
What is another name
for polypeptide chain?
A.
B.
C.
D.
Protein chain
Carbohydrate chain
Lipid chain
Nucleic acid
Translating mRNA codes into amino
acids to create polypeptid chains
(protein chains)
#1. AUG GCA UCC UGA
Methionine, Alanine, Serine, Stop
#2. AUG CCC GGU UAG
Methionine, Proline, Glycine, Stop
#3. AUG AAG GUG UGA
Methionine, Lysine, Valine, Stop
What is the amino acid for the
following codons?
AAU
Asparagine
(Asn)
GUG
Valine
(Val)
UGG
Tryptophan
(Trp)
How can knowing amino acid
sequences in organisms help
biologists?
We can use the sequences to see how organisms are related!
Which of the following two organisms
are MOST closely related?
Fish Sequence: Methionine, Isoleucine, Arginine, Isoleucine, Glycine, Serine
Lizard Sequence: Methionine, Isoleucine, Serine, Glycine, Alanine, Tyrosine
Frog Sequence: Methionine, Isoleucine, Serine, Leuicine, Lysine, Lysine
Bird Sequence: Methionine, Isoleucine, Serine, Glycine, Alanine, Valine
The end…
For now…
DNA Mutations
& Technology
What are genetic mutations?
Mutation: Permanent change in a cell’s DNA,
ranging from changes in a single base pair to
deletions of large sections of chromosomes.
Causes of mutations include:
* Viruses
* Radiation
* Chemicals
* Errors during mitosis and meiosis
Are mutations harmful?
Some mutations are harmful, some are
beneficial, and some do nothing.
Harmful example:
- Some mutations cause cancer & genetic disorders
Are mutations harmful?
Helpful example:
- Sickle cell anemia prevents malaria
Are mutations harmful?
Not harmful or helpful:
- Peppered moths come in dark or light colors
What are some types of mutations?
There are many different types:
Chromosomal mutations
1.
Insertion
What are some types of mutations?
2. Deletion
What are some types of mutations?
3. Translocation
What are some types of mutations?
4. Duplication
What are some types of mutations?
Gene mutations
Point mutations involve changes in one
or a few nucleotides
1. Substitutions: one base is changed
to a different base. Only affects one
amino acid or has no effect at all.
What are some types of mutations?
Gene mutations
Point mutations involve
changes in one or a few
nucleotides
2. Insertions and
deletions: one base is
inserted or removed
from the DNA sequence.
These are called
frameshift mutations
because they shift the
“reading frame” of the
genetic message.
How has technology changed DNA?
Genetic Engineering: Technology used to manipulate an
organism’s DNA by inserting the DNA of another
organism.
Transgenic Organism: Organism that is genetically
engineered by inserting a gene from another organism.
How has technology changed DNA?
Gel Electrophoresis: Process that involves using electric
current to separate certain biological molecules by size.
We use this to see DNA fragments to create a DNA fingerprint
- DNA fingerprints have 2 major uses:
1.Solve crimes
2.Figuring out “who’s the baby’s daddy”
DNA Fingerprinting
Which of the following are his/her parents?
Who did it?
What is the human genome?
Genome: Total DNA in each cell nucleus of an organism
The Human Genome Project:
* Began in 1990 and completed in 2003
* Found that we have 3 BILLION chemical base pairs
* Used to understand genetic disorders
What is cloning?
Cloning: Process in which large numbers of identical
recombinant DNA molecules are produced.
“Dolly” the sheep was the first cloned animal