GUIDED PRACTICE
RESTRICTION ENZYME WORKSHEET #1
Name:
A natural enemy of bacteria is a virus. To defend when attacked by a virus, bacteria use chemrcal
weapons that break up the DNA of the virus. The action of these chemicals on the viral DNA is
shown in the diagram below.
EIAdR-AMI]
TACCGG G
AT GGC C c
c ATCCG GTG
TAGC GTAC
cAc
n
ATCGCATG
n
V
V
TAGGC
n
tl
tl
tl
(tI
V
TACCGG G
ATGGCC CTTAA
AATTCATCCGGTG
GTAGGCCACTTAA
tl
tl
AATT C TAGC
TAC
GATCGCATG
G
Use the diagram above to complete the sentences or answer the following questions:
1.
The chemical that cuts the DNA is called a restnction enzyme. Restriction enzymes cut
the
2.
DNA into
The restnction enzyme used above is called EcoRI. EcoRI cuts DNA everywhere the
base pattern
Copynght O ,l993 by Trustees of Boston University
is found.
Pre-lab Page 17 of22
GLIIDED PRACTICE
RESTRICTION ENZYN,IE WORKSHEET #1 (continued)
Name:
Another restnction enzyme is calie d HaeIII. It cuts DNA at the following base sequence:
CCGG
GGCC
It cuts between the C and the G
as
follows:
I
C CIGG
I
GGlcc
1.
Show the DNA fragmen
shown in diagram l.
that
ld result if HaeIII was used to cut t he DNA fragment
TAECGGGA A TT EATCCGGTGAATTCTA GC GTAC
ATGGC C CT T AA GTAGGC CAC TTAAGAT CGCATG
2.
Do you think restnction enzymes could be used to cut DNA from other organisms?
3.
The words BOB and MADAM are palindromes. What are palindromes?
4.
What do palindromes have to do with the restriction enzymes that cut DNA?
Copynght @ 1993 by Trustees of Boston University
Pre-lab Page l8 of22