Download 8.1 study guide KEY

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SECTION
8.1
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IDENTIFYING DNA AS THE GENETIC MATERIAL
Study Guide
KEY CONCEPT
VOCABULARY
DNA was identified as the genetic material through a series
of experiments.
bacteriophage
MAIN IDEA: Griffith finds a "transforming principle."
Write the results of Griffith's experiments in the boxes below.
Expetiments
1
2
3
4
Results
lnjected mice with
R bacteria
Mice Lived
lnjected mice with
S bacteria
Mice died
Killed S bacteria and injected
them into mice
Mixed killed S bacteria with
bacteria and injected them
into mice
mice lived
R
mice died
Found live S
bacteria in the
mice's blood
c
o
o
E
()o
.c
+
=c
E
O)
l
o
I
5.
a)
The S form
'J
õo)
J
o
oo
oP
c
o
o
()o
Which type of bacteria caused disease, the S form or the R form?
6.
What conclusions did Griffith make based on his experimental results?
Griffith concluded that a transforming principle had been transferred from the heat-killed S
bacteria to the live R bacteria.
Unit 3 Besource Book
McDougal Littell Biology
Study Guide 61
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STUDY GUIDE, CONTINUED
MAIN IDEA: Avery identifies DNA as the transforming principle.
7. Avery and his team isolated Griffith's transforming principle and performed
three tests
to learn if it was DNA or protein. In the table below, summarize Avery's work by writing
the question he was asking or the results of his experiment.
Avery's Ouestion
Results
What Çpe of molecule does the transforming
princlple contain?
DNA is present, but protein is not.
What is the chemical makeup of the
transforming principle?
Which type of enzyme destroys the ability of
the transforming principle to function?
The ratio of nitrogen to phosphorus in the
transforming principle is similar to the ratio
found in DNA.
enzymes that destroy DNA.
MAIN IDEA: Hershey and Chase confirm that DNA is the genetic material.
8.
Proteins contain
sulfer
but very little
phosphorus
9.
DNA contains phosphorus
but no
sulfer
1O. Summarize fhe two experiments performed by Hershey and Chase by completing the
table below. Identify what type of radioactive label was used in the bacteriophage and
whether radioactivity was found in the bacteria.
Experiment
Experiment
Bacteriophage
1
sulfer
Bacteria
C
o
oE
o
O
c
=Co
radioactivity absent
E
o)
l
o
I
Experiment 2
phosphorus
radioactivity present
c)
F
'a
G
o)
l
o
ôU
Vocabulary Check
11. Explain what
a bacteriophage is and describe
or sketch its structure.
€,
E coat.
A bacteriophage is a virus that infects bacteria. It consists of a DNA molecule surrounded by a protein'o
o
o
O
62
study Guide
Unìt 3 Besource Book
McDougal Littell Biology