BIO 313 Exam 3 Review
Ch. 16, 17, 21, 5-7
Supplemental Instruction
Iowa State University
Leader:
Course:
Instructor:
Date:
Laura
Bio 313
Dr. Tuggle
10/25/15
1. Which of the following is not a level of gene regulation?
a. Alteration of DNA structure
b. mRNA processing
c. Posttranslational modification
d. Rate of replication
2. DNA binding motif that is characterized by two alpha helices is known as
a. Leucine Zipper
b. Zinc Finger
c. Helix-turn-Helix
d. Helix-loop-Helix
3. Draw the basic structure of an operon:
4. Continuously expressed genes under normal cellular conditions running the
factory building is known as
a. Positive control
b. Constitutive expressed
c. Negative control
d. Inducibly regulated
5. Fill in the important characteristics of each
Negative inducible
Positive inducible
Negative repressible
Positive repressible
6. The lac operon is a ________ _________ operon
a. Negative repressible
b. Positive repressible
c. Negative inducible
d. Positive inducible
7. In the presence of allolactose, the lac repressor
a. Binds the operator
b. Binds the promoter
c. Cannot bind the operator
d. Binds to the regulatory gene
8. What is the effect of high levels of glucose on the lac operon
a. Transcription is stimulated
b. Little transcription takes place
c. Transcription is not affected
d. Transcription may be stimulated or inhibited, depending on the levels of
lactose
9. In trp operon, what happens to the trp repressor in the absence of tryptophan?
a. It binds to the operator and represses transcription
b. It cannot bind to the operator and transcription takes place
c. It binds to the regulator gene and represses transcription
d. It cannot bind to the regulator gene and transcription takes place
10. Molecules that influence the formation of secondary structures in mRNA
a. Ribozymes
b. Riboswitches
c. Antisense RNA
d. Molecular chaperons
11. Chromatin structure is controlled by all of the following except
a. DNase I hypersensitivity
b. Histone modification
c. DNA methylation
d. DNA binding proteins
12. What is the function of an insulator?
a. To enhance the effect of an enhancer
b. To block all effects of the enhancer
c. To block long range effects of the enhancer
d. To enhance only a specific enhancer
13. Match the term to the definition
Term
Complete dominance
Definition
Phenptype of the heterozygote is
intermediate (Falls within the range)
between the phenotype of the two
homozygotes
Incomplete dominance
The percentage of individuals having a
particular genotype that express the
expected phenotype
Codominance
Penetrance
Expressivity
The degree to which a character is
expressed; strength of phenotype
Phenotype of the heterozygote is the same
as the phenotype of one of the
homozygotes
Phenotype of the heterozygote includes the
phenotypes of both homozygotes
14. A child has type A blood. The genotypes of the parents could be any of the
following except:
a. IAIA x IBi
b. IAIB x ii
c. ii x IBii
d. IAIB x IAIB
15. Match the term to the definition
Term
Sex-linked characteristic
Definition
Autosomal genes whose expression is
limited to one sex
Sex-influenced characteristic
Genes whose expression is affected by the
sex of the transmitting parent
Sex-limited characteristic
Cytoplasmic genes, which are usually
inherited entirely from only one parent
Genes located on the sex chromosome
Genetic material maternal effect
Nuclear genotype of the maternal parent
Cytoplasmic inheritance
Genomic imprinting
Genes on autosomal chromosomes that are
more readily expressed in one sex
16. Epigenetics effects all of the following except
a. Stress levels
b. Cognition
c. Metabolism
d. Likelihood of having twins
17. Which of the following is a disadvantages of humans of experimental subjects
a. Enormous biological info
b. Extensive genetic records
c. Long generation time
d. Large family size
18. What inheritance pattern is seen below?
19. Why do you have twin studies? What is their purpose?
20. What are Mendel’s 2 laws? Include the definitions!
21. What would be the gametes from the F1 generation? Indicate which ones would
be recombinants.