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9.1 Manipulating DNA
•Set up Cornell Notes on
pg. 13
•Topic: 9.1 Manipulating
DNA
•Essential Question:
1. Suppose you cut DNA.
You know that you
should find four DNA
fragments on a gel, but
only three appear, and
one fragment is very
large. Explain what
happened?
9.1Ions,
Manipulating DNA
2.1 Atoms,
and Molecules
1. Suppose you cut DNA. You know
that you should find four DNA
fragments on a gel, but only three
appear, and one fragment is very
large. Explain what happened?
KEY CONCEPT
Biotechnology relies on
cutting DNA at specific
places
9.1 Manipulating DNA
Points to Ponder
A natural disaster strikes. Families are
separated. How can they be reunited?
If a body is found and the person cannot
be identified by looks, how can we identify
them?
What types of identifiers do we have?
9.1 Manipulating DNA
A natural disaster strikes. Families are separated. How
can they be reunited?
If a body is found and the person cannot be identified by
looks, how can we identify them?
What types of identifiers do we have?
• DNA- skin, sperm, saliva, blood
• Fingerprinting
• Teeth
9.1 Manipulating DNA
Sydney Leslie Goodwin 1910-1912
• Died in the sinking of the RMS Titanic
• Known as “The Unknown Child”
• The Goodwins and their 6 children were
third class passengers and all perished
• Finally identified in 2007 using DNA
9.1 Manipulating DNA
KEY CONCEPT
Biotechnology relies on cutting DNA at specific
places.
Baby 81 was
rescued after the
2004 Indian Ocean
tsunami. He was
reunited with his
parents by using
DNA
fingerprinting
technology
9.1 Manipulating DNA
Biotechnology allows us to
•
•
•
•
Produce transgenic organisms
Clone
Study diseases and evolution
Produce medical treatments for people with illnesses
9.1 Manipulating DNA
• DNA cannot be picked up and rearranged by hand
• Therefore, scientists must be able to work with DNA
without being able to see it, or handle it directly
9.1 Manipulating DNA
Scientists use several techniques to manipulate DNA.
• Chemicals, computers, and bacteria are used to work
with DNA.
• Scientists use these tools in genetics research and
biotechnology.
9.1 Manipulating DNA
• Restriction enzymes act as “scissors” by cutting DNA
– allow scientists to more easily study and manipulate
genes
– cut DNA at a specific nucleotide sequence called a
restriction site
DNA
Restriction
enzyme
9.1 Manipulating DNA
• Different restriction enzymes cut DNA in different
ways.
– each enzyme has a different restriction site
9.1 Manipulating DNA
– some cut straight across and leave “blunt ends”
– some make staggered cuts and leave “sticky ends”
Sticky
ends
9.1 Manipulating DNA
Between what nucleotides does this restriction enzyme cut
between?
T and C or
C and T
9.1 Manipulating DNA
Restriction enzyme: cuts between T and A
ATTACGACCTAGGACG
1. How many fragments are produced?
2. Are all the fragments the same length?
3. Please organize the fragments from biggest to
smallest.
4. How many nucleotides in each segment when
organized?
9.1 Manipulating DNA
Restriction enzyme: cuts between T and A
ATTACGACCTAGGACG
How many fragments are produced? 3
Are all the fragments the same length? No
Please organize the fragments from biggest to
smallest. ACGACCT/AGGACG/ATT
How many nucleotides in each segment when
organized? 7, 6, 3
9.1 Manipulating DNA
• Restriction Enzyme Video
9.1 Manipulating DNA
•
After DNA has been cut, several different things can be
done with it
– The gene can be studied
– The gene can be placed in another organism
• But first, the DNA fragments have to be separated
from one another
• Sorted according to their size
9.1 Manipulating DNA
• Gel electrophoresis is used to separate DNA fragments
by size.
– A DNA sample is cut with restriction enzymes
– Electrical current pulls DNA fragments through a gel
9.1 Manipulating DNA
– Smaller fragments move faster and travel farther
than larger fragments
– Fragments of different
sizes appear as bands
on the gel
9.1 Manipulating DNA
• A restriction map shows the lengths of DNA fragments
between restriction sites.
– only indicate size, not
DNA sequence
– useful in genetic
engineering
– used to study
mutations
9.1 Manipulating DNA
Restriction enzyme: cuts between T and A
ATTACGACCTAGGACG
Please organize the fragments from biggest to
smallest.
ACGACCT (7)
AGGACG (6)
ATT (3)
9.1 Manipulating DNA
-
Grab 3 colors. Please organize the fragments from
biggest to smallest.
ACGACCT (7)
AGGACG (6)
ATT (3)
Draw and
complete this
restriction map
on pg. 12
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9.1 Manipulating DNA
“Who Ate the Cheese?” Warm-Up
• Please complete the warm-up by yourself
9.3 DNA Fingerprinting
Who Ate the Cheese?
Practice Gel Electrophoresis-Restriction Enzyme Lab
• Get into pairs
– Each pair needs a Bio book
– Read the Royal Incident Report
– The restriction enzyme used will always cut between
CCGG
– Create you DNA Fingerprint restriction map
CC GG
Objective: You will examine crime evidence and model
the process of gel electrophoresis and DNA
fingerprinting to identify the person who ate the Queen’s
cheese.