1. Which of the following statements concerning the tympanic cavity is correct?
A. It is of endodermal origin*
B. It develops from pharyngeal pouch 3
C. The malleus and incus develop from pharyngeal arch 3
D. The stapes develops from pharyngeal arch 4
2. The neurectoderm gives rise to the
A. dilator pupillae muscle
3. Which pharyngeal arch arteries give rise to the majority of the vessels that supply blood to the head and neck?
A. Pharyngeal arch arteries 1
B. Pharyngeal arch arteries 2
C. Pharyngeal arch arteries 3*
D. Pharyngeal arch arteries 4
E. Pharyngeal arch arteries 6
4. What is the origin of the definitive myocardium of the adult heart?
B. Somatopleuric mesoderm
C. Splanchnopleuric mesoderm*
DENT 5315 Name: _________________________
Quiz 4 (1/30/07)
1. The proximal convoluted tubules of the definitive adult kidney are derived from the:
Is the only layer of enamel organ that is closest to blood vessels
Will form the ameloblasts*
Becomes the dental pulp
Will combine with cells of dental papilla to form the root sheath
From which of the following is the periodontal ligament derived
Epithelial root sheath
Permanent mandibular 2nd premolar tooth bud will develop:
Anterior to mandibular deciduous 2nd molar
Lingual to mandibular deciduous 2nd molar*
Posterior to mandibular deciduous 2nd molar
As a separate tooth bud buccal to the mandibular deciduous 2nd molar
QUIZ DENT 5315/OBIO 8024 Oral Histology, Embryology, and Genetics 2-20-2007
Circle the TRUE statements in the following list: (4 statements are TRUE.)
A. Erosion and caries are similar in that both involve a chemical insult to the tooth.*
B. Circumpulpal dentin and Hertwig's epithelial root sheath have the same embryological origin.
C. The organic content of enamel is a crystalline calcium phosphate (hydroxyapatite) substituted with carbonate ions.
D. Secondary dentin develops after root formation has been completed and continues throughout the life of the tooth.*
E. A layer of predentin is always found between odontoblasts and the mineralization front in dentin.*
F. Impaired translucence of enamel creates optical white spots.*
G. Enamel formation always precedes dentin formation.
H. The primary function of ruffle-ended ameloblasts is to remove water and proteins from enamel.
I. Von Korff fibers participate in the formation of dental cysts.
J. Dentin is a nonvital tissue, incapable of regeneration.
1. Retinoblastoma is inherited as a dominant but on the cellular level behaves like a recessive. What does this mean?
A. All cells with the mutation are cancer.
B. The patient who inherits the mutant gene will never develop cancer.
C. Both parents must have a mutant gene to develop cancer.
D. A person inherits a mutant gene, but a second “hit” must occur in the normal copy of the gene for the cell to become cancer.*
2. Which ONE of the following statement is TRUE about Lyon’s hypothesis:
A. One Y chromosome is randomly inactivated in each cell
B. Both X chromosomes are inactivated in each cell
C. One X chromosome is randomly inactivated in each cell*
D. None of the above
3. Fred Jones is red-green color blind as is his son, Frank, but Frank’s mom, Freida, is not. However, as an expert in genetics, you know that red-green color blindness is inherited in an X-linked recessive pattern. What is the most likely explanation for the apparent inheritance of this trait in this family?
Color blindness is a sex-limited trait occurring only in males
Frank is probably not Fred’s biologic offspring
Frank has a new mutation for red-green color blindness
Freida is a carrier (heterozygote) for red-green color blindness*
4. All of the following statements are true about transmission of classic autosomal dominant disorders EXCEPT:
A. It is seen in multiple generations with no skipping of generations
B. Roughly both males and females are equally affected