Biology TEKS Correlations
(6) Science concepts. The student knows the structures and functions of nucleic
acids in the mechanisms of genetics. The student is expected to:
(A)describe components of deoxyribonucleic acid (DNA), and illustrate how information for specifying the traits of an organism is carried in the DNA;
viral protein coat
labeled with
radioactive sulfur
viral DNA
labeled with
radioactive phosphorous
bacterial DNA
4.
E. Coli bacteria
In 1952, Alfred Hershey and Martha Chase used radioactive isotopes to label a virus called a bacteriophage.
They exposed E. coli bacteria to the viruses and found that most of the radioactive phosphorus was found
in the interior of the bacterial cell. What question were Hershey and Chase most likely trying to answer?
A.
B.
C.
D.
What is the structure of a bacteriophage’s proteins?
Will a bacteriophage transfer diseases to bacteria?
Can radioactive isotopes be used to label cell compounds?
What compound in bacteria carries the genetic information?
This item assumes that students will have been exposed to the historical aspects of the
discovery of DNA. Students may have not studied Hershey and Chase in particular, but by
studying the artwork, they should be able to deduce the correct answer.
5.
When DNA is extracted from the red algae Polyides rotundus, 32% of the nitrogen bases are guanine. Based
on this information, what percentage of the bases are most likely adenine?
A.
B.
C.
D.
9%
18%
36%
64%
This student expectation asks students to know about the structure of DNA. Many items just
ask the students to pair the nitrogen bases and recite the parts of a nucleotide. This item asks
students to apply this knowledge in a different manner.
Charles A. Dana Center
Science TEKS Toolkit
www.sciencetekstoolkit.org
6.
The genetic instructions for an organism are contained in the DNA molecule. The instructions for a specific
organism are determined by the —
A.
B.
C.
D.
number of nucleic acids in the DNA molecule
length of the DNA molecule
sequence of the nitrogen bases in the DNA molecule
type of nitrogen bases in the DNA molecule
The TEKS student expectation also asks students to understand how DNA codes for traits. This
item addresses this part of the TEKS. Notice that an item does not have to address the entire
TEKS statement. It is important that students be asked to look at an idea in many different ways,
and not just in the way that the book or a worksheet states it.
Charles A. Dana Center
Science TEKS Toolkit
www.sciencetekstoolkit.org