Before You Begin
is the process of taking a
gene from one organism and inserting it into
the DNA of another organism. The gene is
delivered by a ,such as a virus, or a
bacterial.
First, a fragment of a chromosome
that contains the gene is isolated by using a
,which cuts DNA at a spe-
cific nucleotide-base sequence. Some restriction
enzymes cut DNA unevenly, producing single-
stranded .The DNA of the vector is
cut by the same restriction enzyme. Next, the
chromosome fragment is mixed with the cut
DNA of the vector. Finally, an enzyme called
joins the ends of the two types of
cut DNA, producing.
In this lab, you will model genetic
engineering techniques. You will simulate
the making of recombinant DNA that
has a human gene inserted into the DNA
of a plasmid.
1.Write a definition for each boldface term
in the paragraph above and for the term
base-pairing rules.
2.Based on the objectives for this lab, write a
question you would like to explore about
the process of genetic engineering.
Procedure
PARTA: Model Genetic Engineering
- Make 56 model nucleotides. To make
a nucleotide, insert a pushpin midway
along the length of a 3 cm piece of a soda
straw. CAUTION: Handle pushpins care-
fully. Pointed objects can cause injury.
Push a paper clip into one end of the soda-
straw piece until it touches the pushpin.
2.Begin a model of a bacterial plasmid by
arranging nucleotides for one DNA strand
in the following order: blue, red, green, yel-
low, red, red, blue, blue, green, red, blue,
green, red, blue, blue, green, yellow, and
red. Join two adjacent nucleotides by
inserting the paper clip end of one into the
open end of the other.
3.Using your first DNA strand and the base-
pairing rules, build the complementary
strand of plasmid DNA. Note:Yellow is
complementary to blue, and green is comple-
mentary to red.
4.Complete your model of a circular plasmid
by joining the opposite ends of each DNA
strand. Make a sketch showing the sequence
of bases in your model plasmid. Use the
abbreviations B, Y, G, and R for the pushpin
colors. Your sketch should be similar to the
one at the top of the next page.
recombinant DNA
DNA ligase
sticky ends
restriction enzyme
plasmid
vector
Genetic engineering
Exploration Lab
Modeling Recombinant DNA
SKILLS
- Modeling
- Comparing
OBJECTIVES
- Constructa model that
can be used to explore
the process of genetic
engineering. - Describehow recombinant
DNA is made.
246 CHAPTER 11Gene Technology
MATERIALS
- paper clips (56)
- plastic soda straw
pieces (56) - pushpins (15 red, 15
green, 13 blue, and
13 yellow)
1B 2A 2C 2D 3E 6A