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:
14.
In mice, black coat color (B) is dominant to brown coat color (b). A second gene controls the intensity of
the coat color. Full coat color (D) is dominant to faded coat color (d). If a mouse with a genotype of BBDd
is crossed with a mouse of BBdd, what percentage of the offspring will most likely show a faded black
phenotype?
A.
B.
C.
D.
15.
(D)compare genetic variations observed in plants and animals;
0%
25%
50%
100%
Fragile X syndrome is the most common inherited form of mental retardation. Fragile X is caused by a
mutation in a gene located on the X chromosome. Fragile X affects more males than females because —
A.
B.
C.
D.
males inherit only one X chromosome
the X chromosome in females is able to correct the mutation
mutation rates are lower in females than in males
there are more males in the population
This item does not require the student to be familiar with all the types of human genetic
diseases; it does require that they have spent some time studying genetic variations. This
would involve more than just completing Punnett squares.
AaBbCcDd x AaBbCcDd
16.
What is the probability of the parents above producing the genotype AaBbccDD?
A.
B.
C.
D.
17.
1/2
1/16
1/32
1/64
A person with blood type AB has both IA and IB genes. The type AB blood expresses the characteristics of
both A and B blood types. This is an example of which type of inheritance?
A.
B.
C.
D.
Codominance
Incomplete dominance
Sex-linked
Nondisjunction
Item 16 is from Region VII Education Service Center’s TEKS Assessment Generator test bank. Used with permission.
Charles A. Dana Center
Science TEKS Toolkit
www.sciencetekstoolkit.org